The Search For Accuracy

[joeb33050]

I gave up on IMR4198 as the most accurate powder for cast bullet loads a while back; after trying it in rifles from 22 Hornet to 45/70. This powder used to be found on equipment lists, it is seen there much less frequently now.
Accuracy tests are five, five shot groups at 100 yards, with the average of the five group sizes being the important number.
The accuracy search with my M54 Winchester in .30 WCF has gone on for well over three years and 521 five shot 100 yard groups. Thye gun averaged 1.479" over all those groups, and it is probably true that I could average about 1.3" or less picking the best loads. This gun was made in 1928, has a skinny barrel and a very heavy trigger pull-very heavy.
Six weeks ago one of the shooters at the Trail Glades Range in Miami suggested I try IMR4198. I did, and things got better very quickly. The rifle seems to now shoot the best loads into about 1.1" or better. The difference between the "old" 1.3" and "new" 1.1" doesn't seem like much, but the difference on the targets is substantial; with many groups having 3 or 4 shots clustered tightly or in the same hole. I can see that the trigger is now the limiting factor; with a good letoff the holes cluster tightly together. With a good trigger this gun would shoot averages under 1" reliably.
This experience opened my eyes to the fact that my search for accuracy was not well organized and that I've never read of an accuracy search procedure.
What am I talking about?
An example:
With any reasonable 45/70 rifle, any reasonable bullet lubricated with Darr lube, with any reasonable primer and 14 grains of Unique, five shot group averages of under three inches, and generally under 2 1/2 inches are easily made.
Let's say that we're at a 2 1/2 inches, we can shoot five five shot 100 yard groups and average around 2 1/2".
And let's say that we want to get the rifle shooting smaller groups.
What do we change next?
The things we CAN change are legion. The things we SHOULD change are limited somewhat by costs, but should follow some reasonable scheme that works.
We could uniform primer pockets and try again, but that probably isn't the best next step. I guess that what I'm looking for is the best next step or steps; a list of what to try next in the search for accuracy in a rifle with cast bullets.
Sights matter. With good peep rear and aperture front sights, or telescopic sights, very good accuracy can be achieved. I can't shoot well with "v" or "U" rear sights and post front sights, and think it is difficult for us old guys to shoot well for accuracy with lesser sights, so this is limited to rifles with good irons or scopes.
Rifle accuracy, as defined by the average of five five shot groups at 100 yards, comes in clumps.
My experience is that it is pretty easy to get any rifle to shoot around 2"-the exceptions being the heavy-recoiling calibers like 45/70.
Getting to 1 1/2" is a little more difficult, but some work and we can get there.
Below 1 1/2" takes some doing, yet most rifles can get there.
Now 1" and below is tough. Based on the CBA National records over several years, competitors average around 1" over the classes. Means that those who shoot in each of the four classes, all told, average about 1". Averaging 1" with cast bullets is tough.
So, where is this going?
I'm going to put together an article for the book about The Search For Accuracy, and I need some help-a lot of help.
We need to know how to check, measure and fiddle with the gun.
We need a list of variables, primer and powder and OAL and powder charge and brass trimming,primer pocket uniforming, flash hole deburring, and wads/fillers and sizing and brass weights and alloy and bullet choice and lube and amount of lube and gas check type/use and who knows what else.
Then we need to put the variables together with the accuracy clumps.
So, in the example, the easiest and cheapest change we can make is to the powder charge-trying 13.5 gr. and 14.5 gr. next time out.
That's where I'm going; want to help?
joe brennan

[Wayne Smith]

First of all you need to separate, as far as possible, variables relating to rifle accuracy and variables relating to shooter accuracy and variables relating to the interface between the shooter and the rifle. In the latter we have such variables as trigger pull and stock fit, in the median we have variables such as recoil sensitivity, steadiness, shooting position, etc. and in the first we have what many here mean as accuracy, the accuracy of the rifle, the cartridge, the stock bedding, the fit of the bullet, internal and external ballistics.

Books have been written on each of these sets of variables. Within each set of variables you can break down other subsets of variables, and on and on. How big a book were you intending to write??

[joeb33050]

[QUOTE=Wayne Smith;237432]First of all you need to separate, as far as possible, variables relating to rifle accuracy and variables relating to shooter accuracy and variables relating to the interface between the shooter and the rifle.QUOTE]
No, Wayne, I don't. Don't feel the need at all. This is difficult enough without introducing any number of perhaps imaginary issues.
Thanks anyhow;
joe b.

[felix]

Joe, you already know from past books, boards, and your pertinent experience. You just have to do it for your specific guns. ... felix

[Bass Ackward]

Joe, you already know from past books, boards, and your pertinent experience. You just have to do it for your specific guns. ... felix



Joe,

Felix is right. Throat configuration will change what steps I alter first. Same with the chosen bullet design. Same with caliber. It all depends based on what I have seen to statistically make a difference. But in the end, I still have to try everything or be comfortable with results I produce. When satisfaction sets in, all experimentation stops.

It's not so much a "requirement" for specific steps, only that "your search" should be methodical and comprehensive. Like if you change diameter. You can't just change diameter without a full work up of load. Meaning that hardness, lube quality, bullet design, all factor in. Essentially, you must go back to square one and start all over.

Everyone wants to believe that the best cast bullet accuracy occurs at lower levels. Well, I say the easiest accuracy occurs there. It's THE SAME with jacketed. You can shoot jacketed with virtually any powder at low pressure before jacketed obturates and creates more friction, and find good accuracy. But I always find the best accuracy on up the scale. It's the same with cast. Create more friction with more pressure on the base and resonant harmonics change which complicates the issue much more, but it shouldn't stop you unless you RPMize it and give up.

At high velocity, with either metal, is where you REALLY have to be methodical and comprehensive. The better you are, the more success you will have. If you are a person that likes to try what someone else does, then you stand a much better chance with jacketed. Period. Primer can make or break ya with HV cast. And just because one primer shoots better then, you can change diameter or hardness or any of a few other variables and have the poor performing primer from before turn out to be the best one of all.

You just can't pick a load or a lube, load what someone else claims and say, why can't I do it. Your rifle may require 5 more BHN to do the same thing.

So what you are really looking for is a list of what variables are possible to change. Cause everyone is important when it is the one that makes all the difference. Look at me, I use magnum primers for squib loads and pistol primers for hot ones. And that list needs to be two fold. A list of those items, like brass preparation, which are done only once or intermittently / periodically. And those items that need to be done with each variable change.

[joeb33050]

Joe, you already know from past books, boards, and your pertinent experience.
No, Felix, I don't know the proper or reasonable order of steps. And neither do you.



You just have to do it for your specific guns. ... felix

No, Felix, there's a reasonable procedure that applies to ALL rifles under the stated conditions. Rifles aren't all that different.

Does this mean that you don't want to help? Brief comments from the mountaintop are entertaining, but sometimes some actual work is required.
joe b.

[joeb33050]

Bass;
As usual, there are a lot of words here.
If you wish to believe that attaining accuracy with cast bullets in rifles is so complex a process that only the anointed can succeed, God love you. If you want to believe that best cast bullet accuracy is found at high velocities, God love you. Show us some match results.
It ain't that hard, it ain't that complex, it ain't that difficult; unless you make it such.
I'm going to do it.
Want to help?
joe brennan




Joe,

Felix is right. Throat configuration will change what steps I alter first. Same with the chosen bullet design. Same with caliber. It all depends based on what I have seen to statistically make a difference. But in the end, I still have to try everything or be comfortable with results I produce. When satisfaction sets in, all experimentation stops.

It's not so much a "requirement" for specific steps, only that "your search" should be methodical and comprehensive. Like if you change diameter. You can't just change diameter without a full work up of load. Meaning that hardness, lube quality, bullet design, all factor in. Essentially, you must go back to square one and start all over.

Everyone wants to believe that the best cast bullet accuracy occurs at lower levels. Well, I say the easiest accuracy occurs there. It's THE SAME with jacketed. You can shoot jacketed with virtually any powder at low pressure before jacketed obturates and creates more friction, and find good accuracy. But I always find the best accuracy on up the scale. It's the same with cast. Create more friction with more pressure on the base and resonant harmonics change which complicates the issue much more, but it shouldn't stop you unless you RPMize it and give up.

At high velocity, with either metal, is where you REALLY have to be methodical and comprehensive. The better you are, the more success you will have. If you are a person that likes to try what someone else does, then you stand a much better chance with jacketed. Period. Primer can make or break ya with HV cast. And just because one primer shoots better then, you can change diameter or hardness or any of a few other variables and have the poor performing primer from before turn out to be the best one of all.

You just can't pick a load or a lube, load what someone else claims and say, why can't I do it. Your rifle may require 5 more BHN to do the same thing.

So what you are really looking for is a list of what variables are possible to change. Cause everyone is important when it is the one that makes all the difference. Look at me, I use magnum primers for squib loads and pistol primers for hot ones. And that list needs to be two fold. A list of those items, like brass preparation, which are done only once or intermittently / periodically. And those items that need to be done with each variable change.

[Junior1942]

I think the biggest foil to CB accuracy is rpm. Over about 110k rpm--IME--and up pops fliers. The bullets start slinging themselves apart. I'd like to see high speed photos taken at, oh, say, 25 yards, of identical cast bullets in gradually increasing velocities and through the same barrel, i.e., gradually increasing rpms. I bet the photos would show gas checks askew and barrel shaped bullets.

In some of my CB trials with fast military twists, some of the holes in the targets had commas attached. Think an O with an attached comma. IMHO, that was evidence of lead strips about to detach from the bullet.

[felix]

Joe, it is only work when you are scaling a mountain, or attempting to scale, when your heart is not in it and would rather be doing something else. The mountain you want to climb is beyond my capability, and those previous posts should help you get a handle on performing your chore, to me. ... felix

[Bass Ackward]

Bass;
As usual, there are a lot of words here.
If you wish to believe that attaining accuracy with cast bullets in rifles is so complex a process that only the anointed can succeed, God love you. If you want to believe that best cast bullet accuracy is found at high velocities, God love you. Show us some match results.
It ain't that hard, it ain't that complex, it ain't that difficult; unless you make it such.
I'm going to do it.
Want to help?
joe brennan


Joe,

I don't compete. But I know a guy you can ask that has seen my work. Here's the story.

Once upon a time there was a guy on the internet that was seeking help with his 223 Savage. He was trying to use fast powders and lower RPMs and was getting nowhere. He was jumping around with no logical progression to his method. This made him very frustrated. Everyone was jerking this guy from this powder to that without understanding exactly what was happening. Without seeing him, or his gun, I got him to shoot the best groups that rifle ever produced with cast using 4350 powder at a higher velocity.

BUT, .......... this guy was kind of .... stubborn. :grin: If I could have gotten this guy away from monotype to a softer alloy and to another, lighter (non bore ride) bullet design, he could have done WAY better yet, and at a higher RPM level. And he would have been a believer.

So ask him. His name, by the way, was Joe Brennan.

So I already did help, once. :grin:

[Larry Gibson]

I think the biggest foil to CB accuracy is rpm. Over about 110k rpm--IME--and up pops fliers. The bullets start slinging themselves apart. I'd like to see high speed photos taken at, oh, say, 25 yards, of identical cast bullets in gradually increasing velocities and through the same barrel, i.e., gradually increasing rpms. I bet the photos would show gas checks askew and barrel shaped bullets.

In some of my CB trials with fast military twists, some of the holes in the targets had commas attached. Think an O with an attached comma. IMHO, that was evidence of lead strips about to detach from the bullet.

Well, well, there are two of us!

Larry Gibson

[Char-Gar]

Well... This ought to be interesting. I am by no means an expert in all of this, but my guts tell me there should be some principals that apply to all rifles. The principals may have all sorts of exceptions and limitations, but there should be a linear path to accuracy a fellow can follow with his rifle.

I wish anyone well, who want to blaze that path and lay down markers for the unwashed to follow.

[Bret4207]

Ya get more flys with sugar......

[joeb33050]

The Search For Accuracy II

I think there are these parts to the search:
First there's the rifle and scope or irons.
Checkout, lubrication, screw-tightening, scope/irons mounting, stock fit and ???.
The rifle can be new, in which case there's the break in. I've read break in instructions from barrel makers, rifle makers and experienced shooters-never saw much agreement, so I just shoot them.
If the rifle is used, I do a lot of cleaning, until clean patches after brushing.

Second there's measuring the chamber and barrel. Either measure or believe the manufacturer-I measure. ((I've never had a surprise = mfr. differs from reality on twist.)
Chamber/throat slug or casting
Chamber end bore-if possible-and groove dimensions
Muzzle end bore-if possible-and groove dimensions
Tight or loose spots in the bore
Twist

Third there's the beginning sets of loads
Powder
Charge
Primer
Bullet/Mold
Alloy
Sized to
Lube
Gas Check-(while I know that Hornady now makes Lyman gcs, I can't find out if the hornady-made lymans are crimp-on-haven't seen new lymans in a gun store in a while.)
OAL
Filler/Wad
Cartridge cases
Trimming to length and case-mouth chamfering should be done before shooting. Maybe shoot ?? first to fire-form cases to chamber before trim chamfer. All the rest of the case magic, weighing/segregating, primer pocket uniforming, flash hole de-burring CAN be done anytime, but doesn't NEED to be done until much later, when accuracy is ?<1 1/2"?.
Loading procedure
Brush out case necks
Clean primer pockets
Neck size
Bell case mouth/"M" die
Weigh/dribble/throw powder charge--SR4759 vs. AA#9
Seat the bullet


Fourth is the shooting, measuring groups and recording the results
Conditions must be reasonable; no hurricane or blizzard, but no wait for the perfect day. Shoot foulers/sighters and 10 record shots in 15 minutes. No outwaiting the wind.
Decent bench
Decent bench rest and bags. Maybe a $300 bench rest will help at small group averages, but not now. Hoppes rest, or Caldwell, or ??-a decent rest.
Targets matter, for both irons and scope. Black ~6" bull for irons, 3/4" black or blue dot for scope. Some trying is required.
A "pulled shot" = "my fault" = "honker" is only discounted if called before looking through the spotting scope.
Shoot five groups, measure the groups using a plastic ruler marked in .1" increments, caliper, or ??
Average the five
Write it all down
Clean the rifle

Fifth and last and repetitive step is to decide what to do next
If three loads were shot and the average group sizes were 2", 2" and 3/4"; load another set of the 3/4" recipe to try again. If the groups repeat, we're done. If not, it's time to change something.
Here we come to the hierarchy of variables. It makes sense to change powder charge with a 2" average group size, it does NOT make sense to change the powder charge .1 grain, or OAL by .001", or bullet alloy from WW + 2% tin to WW + 3% tin.
The variables have cost and time associated with them.
The process must take this cost and time into account.
I think that the changes might be:
Change one thing at a time only!!
Vary powder charge in .5 grain steps
Try another bullet if you have the molds-keep the bullet choice reasonable. No 88 grain 30 calibers.
Vary the powder charge with the other bullet(s).
Try another powder with varying loads with each bullet

I believe that at the 2" stage of accuracy, varying only the bullet, powder and charge will get us into the 1 1/2" repeatable range.
What do we do then?
joe brennan

[Pat I.]

I think the biggest foil to CB accuracy is rpm. Over about 110k rpm--IME--and up pops fliers.

While I agree whole heartedly that cast bullets are twist limited I don't think you can make a blanket statement what that limit is. Caliber has to be taken into consideration and it seems the smaller the caliber the more RPM the bullet will tolerate, although I do believe they have a limit also. In 30 caliber upward to 130,000 rpm seems to work out pretty well from what the CBA records and match results indicate. The only thing I can base my judgements on like it or not are the CBA match results and records for the simple reason that they're verifiable.

Searching for accuracy while discounting all the things Wayne Smith mentioned is an excercise in frustration. How many times have you had or seen a group that was 3/4 of an inch high by 1 1/2 inches wide orm vis a versa? You could have an excellent load but either bench techique or wind spread it out so that you're not satisfied. Bench rest books don't waste so many words about gun handling, equipment, and wind doping just to fill space.

[Bass Ackward]

While I agree whole heartedly that cast bullets are twist limited I don't think you can make a blanket statement what that limit is. Caliber has to be taken into consideration and it seems the smaller the caliber the more RPM the bullet will tolerate, although I do believe they have a limit also.


Pat,

Well if something is a barrier, then it ought to be a barrier.

Back in the 60s we all bought 22-250s when Remington standardized it. We all wanted 40 grain Speer's to pass the 4000 fps barrier. Everyone crapped at 3500-3600 fps. Except one. Turns out he was using a light coat of oil which allowed 4100 fps. RPMs got the rest of us. :grin:

The RPM barrier for my handguns with PB bullets is 40,000 RPMs. Ahhh .... unless I harden them or change lube. In our minds we have no trouble saying substitute bullet lube or bullet design or change sizing or hardness at this level. Since this is getting close to Halloween, I can say, ah hell, the PB, RPM Monster got me. But there are enough other folks who know that I just needed to change things that that argument wouldn't fly. Statistically there just aren't enough folks that attempt HV with cast to validate my position.

A few years back the CBA Nationals were held in Kansas in temperatures over 100 degrees. Many shooters were turning groups far better than they ever had. The RPM monster took a break that day. Sadly, these guys missed the hint!

IF bench rest matches were allowed to go on with shooters allowed one hour to complete shots with cold barrels, and matches were held in cold weather, it would soon be common knowledge that the RPM barrier changes with temperature. Then a light bulb would go on for more folks that could affect change of minds as opposed to morons and liars like me that constantly ruin their credibility trying to encourage others to try.

When you accept the limit is RPMs, you have simplified the thought process and all hope is lost.

[45 2.1]

When you accept the limit is RPMs, you have simplified the thought process and all hope is lost.

Hahahaha, they're not going to listen John, your wasteing your breath. If you can't get accuracy with something, you ought to listen carefully to people who can.

[montana_charlie]

Although there are a ton of unanswered questions when it comes to finding the most accurate load for a particular gun, your primary question (for this thread) seems to be, "Do you want to help?"

My answer would be 'yes' if I knew a few things.

- Can I help effectively without spilling my coffee?
- Are we going to stay with generalities, or concentrate on a caliber I actually have some experience with?
- Is the goal to find the 'accurate load'...or the 'highest velocity, flattest shooting, most hi-performance load we can squeeze out of a case-hardened, spring-tempered, ultra-sophisticated magic-alloy cast bullet' - while still retaining enough accuracy to brag about the results?

Even if your search is going to head in a direction that I can't help with, I have a tip to donate. One of your musings was...

Cartridge cases
Trimming to length and case-mouth chamfering should be done before shooting. Maybe shoot ?? first to fire-form cases to chamber before trim chamfer.
If 45/70 will be a test bed for the accuracy search, I highly recommend that a choice between shooting fireformed cases...or resized cases...be made before any trimming is considered.
Those cases that will be used in their fireformed dimension should not be length trimmed until after fireforming.

So, I'll watch the thread for a while to see if I can be helpful, but so far the discussion seems to be heading into territory I don't have a compass for.
CM

[Pat I.]

Pat,

Well if something is a barrier, then it ought to be a barrier.

Back in the 60s we all bought 22-250s when Remington standardized it. We all wanted 40 grain Speer's to pass the 4000 fps barrier. Everyone crapped at 3500-3600 fps. Except one. Turns out he was using a light coat of oil which allowed 4100 fps. RPMs got the rest of us. :grin:

The RPM barrier for my handguns with PB bullets is 40,000 RPMs. Ahhh .... unless I harden them or change lube. In our minds we have no trouble saying substitute bullet lube or bullet design or change sizing or hardness at this level. Since this is getting close to Halloween, I can say, ah hell, the PB, RPM Monster got me. But there are enough other folks who know that I just needed to change things that that argument wouldn't fly. Statistically there just aren't enough folks that attempt HV with cast to validate my position.

A few years back the CBA Nationals were held in Kansas in temperatures over 100 degrees. Many shooters were turning groups far better than they ever had. The RPM monster took a break that day. Sadly, these guys missed the hint!

IF bench rest matches were allowed to go on with shooters allowed one hour to complete shots with cold barrels, and matches were held in cold weather, it would soon be common knowledge that the RPM barrier changes with temperature. Then a light bulb would go on for more folks that could affect change of minds as opposed to morons and liars like me that constantly ruin their credibility trying to encourage others to try.

When you accept the limit is RPMs, you have simplified the thought process and all hope is lost.

I hope you don't think I'm calling you or anyone else a liar because I'm not but what some say sometimes is in direct conflict with what I've found so I'm going to question it. You can't blame people for being sceptical with the stuff written on these forums because if all of it was true there's guys breaking jacketed world records with cast every other day. Maybe it's just that our ideas of accuracy are different and for what I'm looking for RPM has a much bigger effect than for what you look for.

I don't understand what you mean about the CBA match held at KC. I was at a nationals at KC a few years ago when it was hotter than hell and while I can't remember there was probably some pretty good shooting and records set but I've been at nationals both before and since when it wasn't as hot and there was some pretty good shooting and records set so what are we missing?

People are going to disagree about things based on their findings but I'm pretty open to having my opinions changed by being shown, not told, I was wrong. I live right outside Chicago and would be more than willing to be shown, again not told, I was wrong both about this topic and the 6.5 topic if there was someone from around here willing to prove it to me on a target. There's a few ranges close by, the ISRA range comes to mind and I'm allowed to bring a guest, but traveling a reasonable distance isn't much of a problem. Just tell me on here what they consider accuracy, what speed they'll get it at, and do it more than once and I'll get on here and admit I was wrong about everything and defend them to the end. Any takers? Oh yeah, and I don't bite the help.

[Pat I.]

Hahahaha, they're not going to listen John, your wasteing your breath. If you can't get accuracy with something, you ought to listen carefully to people who can. [/B]

Not only am I willing to listen I'm willing to attend class and be educated by the very best.

[Bret4207]

The Search For Accuracy II

I think there are these parts to the search:
First there's the rifle and scope or irons.
Checkout, lubrication, screw-tightening, scope/irons mounting, stock fit and ???.
The rifle can be new, in which case there's the break in. I've read break in instructions from barrel makers, rifle makers and experienced shooters-never saw much agreement, so I just shoot them.
If the rifle is used, I do a lot of cleaning, until clean patches after brushing.

Second there's measuring the chamber and barrel. Either measure or believe the manufacturer-I measure. ((I've never had a surprise = mfr. differs from reality on twist.)
Chamber/throat slug or casting
Chamber end bore-if possible-and groove dimensions
Muzzle end bore-if possible-and groove dimensions
Tight or loose spots in the bore
Twist

Third there's the beginning sets of loads
Powder
Charge
Primer
Bullet/Mold
Alloy
Sized to
Lube
Gas Check-(while I know that Hornady now makes Lyman gcs, I can't find out if the hornady-made lymans are crimp-on-haven't seen new lymans in a gun store in a while.)
OAL
Filler/Wad
Cartridge cases
Trimming to length and case-mouth chamfering should be done before shooting. Maybe shoot ?? first to fire-form cases to chamber before trim chamfer. All the rest of the case magic, weighing/segregating, primer pocket uniforming, flash hole de-burring CAN be done anytime, but doesn't NEED to be done until much later, when accuracy is ?<1 1/2"?.
Loading procedure
Brush out case necks
Clean primer pockets
Neck size
Bell case mouth/"M" die
Weigh/dribble/throw powder charge--SR4759 vs. AA#9
Seat the bullet


Fourth is the shooting, measuring groups and recording the results
Conditions must be reasonable; no hurricane or blizzard, but no wait for the perfect day. Shoot foulers/sighters and 10 record shots in 15 minutes. No outwaiting the wind.
Decent bench
Decent bench rest and bags. Maybe a $300 bench rest will help at small group averages, but not now. Hoppes rest, or Caldwell, or ??-a decent rest.
Targets matter, for both irons and scope. Black ~6" bull for irons, 3/4" black or blue dot for scope. Some trying is required.
A "pulled shot" = "my fault" = "honker" is only discounted if called before looking through the spotting scope.
Shoot five groups, measure the groups using a plastic ruler marked in .1" increments, caliper, or ??
Average the five
Write it all down
Clean the rifle

Fifth and last and repetitive step is to decide what to do next
If three loads were shot and the average group sizes were 2", 2" and 3/4"; load another set of the 3/4" recipe to try again. If the groups repeat, we're done. If not, it's time to change something.
Here we come to the hierarchy of variables. It makes sense to change powder charge with a 2" average group size, it does NOT make sense to change the powder charge .1 grain, or OAL by .001", or bullet alloy from WW + 2% tin to WW + 3% tin.
The variables have cost and time associated with them.
The process must take this cost and time into account.
I think that the changes might be:
Change one thing at a time only!!
Vary powder charge in .5 grain steps
Try another bullet if you have the molds-keep the bullet choice reasonable. No 88 grain 30 calibers.
Vary the powder charge with the other bullet(s).
Try another powder with varying loads with each bullet

I believe that at the 2" stage of accuracy, varying only the bullet, powder and charge will get us into the 1 1/2" repeatable range.
What do we do then?
joe brennan

Isn't most of this isolating some of the variables that Wayne mentioned, that you said you didn't need to worry about? Isn't the goal of most shooting for groups to identify the inconsistancies and eliminate them, to identify problem areas, to strive for cosistant methods and components throughout the course of the testing? I'm a little confused on what it is you're asking for if you refuse to consider other ideas and opinions, be it in testing, rpm limits or lack of limits, alloy, platforms used and all the other variables involved, when you seem to be asking for those other ideas and opinions. What exactly is it you want from those you are asking to help you?

[joeb33050]

Isn't most of this isolating some of the variables that Wayne mentioned, that you said you didn't need to worry about? Isn't the goal of most shooting for groups to identify the inconsistancies and eliminate them, to identify problem areas, to strive for cosistant methods and components throughout the course of the testing? I'm a little confused on what it is you're aiming for if you refuse to consider other ideas and opinions, be it in testing, rpm limits or lack of limits, alloy, platforms used and all the other variables involved.

Here's what Wayne wrote:
"First of all you need to separate, as far as possible, variables relating to rifle accuracy and variables relating to shooter accuracy and variables relating to the interface between the shooter and the rifle. In the latter we have such variables as trigger pull and stock fit, in the median we have variables such as recoil sensitivity, steadiness, shooting position, etc. and in the first we have what many here mean as accuracy, the accuracy of the rifle, the cartridge, the stock bedding, the fit of the bullet, internal and external ballistics."
My response was that I do NOT need to separate these variables, do NOT need to follow his model, which includes some probably mythical variables. Wayne follows with the clear implication that the chore I proposed is either extremely difficult or impossible-I don't need anyone to suggest that.

You ask:
"Isn't the goal of most shooting for groups to identify the inconsistancies and eliminate them, to identify problem areas, to strive for cosistant methods and components throughout the course of the testing?"
My answer is that it may be, but so what?

You then ask:
"I'm a little confused on what it is you're aiming for if you refuse to consider other ideas and opinions, be it in testing, rpm limits or lack of limits, alloy, platforms used and all the other variables involved."

First, your confusion. I'm writing a step by step method or procedure for searching for accuracy with a rifle with cast bullets within the framework described above. This will be a "what to do, when" procedure, with none of the "how"-since most of that is covered already.
Next, the rest of yours. I'm here-and elsewhere-looking for help in constructing this accuracy search protocol. I want and need the ideas and opinions of others, as long as they deal with the subject I'm working on.

Test methods?-it's written above. I've spent a lot of time on this, listened to a lot of opinion, and I'm happy with what I wrote.

rpm limits? Go to the book at http://sports.groups.yahoo.com/group/CB-BOOK/, sign in, go to files, and look at the WXCEL worksheet "TWIST MV RPM CALIBER ROTATIONAL SPEED" and see how it works. You can find both the RPM and Rotational speed for any bullet of any caliber at any MV. Now open a loading manual or the CBA match results or search this forum for entries, and try to derive a formula or rule. I can't, doesn't mean it doesn't exist-but I've spent a lot of time trying to understand what the relationship is and can't so far.

alloy? coming

platform used? what do you mean?

all the other variables? such as?

Bret, you seem to be a criticizer, maybe that's what a moderator does. How about some help here? I can't do this alone! Or. I can't do it as well alone as with help.
joe brennan

[joeb33050]

- Are we going to stay with generalities, or concentrate on a caliber I actually have some experience with?

- Is the goal to find the 'accurate load'...or the 'highest velocity, flattest shooting, most hi-performance load we can squeeze out of a case-hardened, spring-tempered, ultra-sophisticated magic-alloy cast bullet' - while still retaining enough accuracy to brag about the results?

Even if your search is going to head in a direction that I can't help with, I have a tip to donate. One of your musings was...

If 45/70 will be a test bed for the accuracy search, I highly recommend that a choice between shooting fireformed cases...or resized cases...be made before any trimming is considered.
Those cases that will be used in their fireformed dimension should not be length trimmed until after fireforming.

CM
MC
generalities? I'm thinking of a cartridge example. Don't know what to choose, maybe .308 or 30/06. Want to pick one and help? 45/70 is some trouble, won't shoot/can't be shot as accurately as a .30. No, I don't want to argue about that, I know there are some who shoot it well under 1" all day.

goal? Most accurate load, sort of normal rifle. Not BPCR, CBA Unlimited Rail Gun, Maynard #16-just a normal rifle between a Savage 340 and Rem 40X

about trimming--You're right, my mistake. This is about WHAT to do, not HOW-since HOW is already in the book. My mistake.
joe b.

[joeb33050]

The Search For Accuracy III

We've agreed that getting from 2" to 1 1/2" group averages can be done by varying powder, charge and bullet. We've agreed since nobody objected.
We haven't addressed the question of what to do if we can't get to 1 1/2" groups. Is a bedding operation called for?

Never mind, how do we get from 1 1/2" to 1" groups-or at least well under 1 1/2"?

Here are the things to vary:
primer
OAL
different (harder) alloys
bullet sizing diameter
lube
(I may have left something out)
I believe that an orderly set of tests changing these elements will get us from 1 1/2" to 1", or at least well under 1 1/2".

What do we do if we can't get well under 1 1/2"?

Next, and last, are the things to vary to get average groups smaller; smaller than 1".
brass make, trim, neck turn, weight, primer pocket uniformity, flash hole de-burring, chamfer, hardness/annealing
bullet weight consistency to ?.2 gr."
powder weight consistency to .1 gr.
OAL in ~.002"? steps
barrel cleaning frequency
lube
bullet size diameter in .001" steps
barrel cooling
orientation
cartridge concentricity

Again, an orderly set of tests changing these elements will get us to well under an inch average group size, if the rifle is capable of getting there.
How do we know when to give up-when the rifle won't shoot any better?

Now this is at least a framework for the method-the how- of searching for accuracy with a cast bullet rifle. I'm sure I've forgotten something important and I'm sure this can be improved, but be wary!!
Adding variables for the sake of adding variables isn't going to help; merely makes to process longer without helping much.
joe b..

[joeb33050]

From another forum:
There are some who say that case runout, if oriented uniformly in the
chamber from shot to shot, can be used to shrink groups.
I understand "case runout" to mean the thickness/thinness of the brass
in the neck area.
So I guess one determines the thickest part of the brass neck, marking
it with a filed notch on the case rim. Then one orients the case with that
part at 12 o'clock in the chamber.
How does one keep a Mauser-type action from rotating the case as the
bolt is closed? Does such an action always rotate every cartridge the
same amount? How would we know?
Does one, perhaps, turn or ream the case neck to achieve uniform
neck wall thickness - thus avoiding the problem?
There is also, perhaps, the need to compensate for an out-of-perfection
chamber where the neck is not coaxial with the bore or the case body
or one or the other.
Best regards
John


My experience is that I've never, not ever, found an increase in accuracy with orienting anything. Also, that there are plenty of shooters who contend that orienting bullet, cartridge, bullet in sizing die, case in sizing die, case and bullet in seating die and on and on, increases accuracy. I have NEVER had a response telling of a test with and without and showing the accuracy results. Doesn't mean it doesn't help, just means I can't get it to help. I've oriented in SS rifles, where it's easier, but always had John's question about the ctg. turninjg in a bolt gun.

joe b.

[Bret4207]

platform used? what do you mean?

all the other variables? such as?

Bret, you seem to be a criticizer, maybe that's what a moderator does. How about some help here? I can't do this alone! Or. I can't do it as well alone as with help.
joe brennan

Platform= Bolt gun, lever, revolver, etc.

Other variables= distance, caliber, wind, eyesight, the way you part your hair, etc. etc. You answered most of that in your later posts.

No Joe, I'm not criticizing, I was asking what it is you are trying to accomplish. This has NOTHING to do with being a moderator, it has to do with my being a contributor here like everyone else and my wondering why and what it is you are pursuing. In your following posts you say, "We've agreed that getting 2" to 1 1/2"......" because no one is disagreeing with you. I look at it more as you have made statements and we're waiting to see your proof, or at least your theory.

You're asking for help for this book you're writing. Great, I support your effort. You have said any information you gather will be credited in the footnotes. Wonderful. You seemed to be a bit stressed over this project. I would think if you want help with researching this you would welcome any ideas or opinions rather than dismissing outright what you don't agree with.

Whenever we enter into a research project we can't help but have preconceived notions and opinions. As I understand it the biggest hurdle in research is accepting what doesn't fit those notions or the template you had in mind. You can get miffed and consider my questions "criticizing" if you wish. I just don't see how you can expect much help if you push away those trying to assist you.

Best of luck with your project Joe.

[joeb33050]

The Search For Accuracy-The Numbers

Sets of five five shot groups will, on average, have the largest group twice the size of the smallest. Hence, I'm leery of small numbers of groups, or small numbers of shots in a group.
If what's written (way) above is more or less correct, it is somewhere between difficult and impossible to shoot the numbers of groups required.

If powder, charge and bullet are the variables getting us from 2" to 1 1/2" groups, how many tests are required?
Let's say that we vary only one thing at a time.
Let's say that we have 2 powders and two bullets.
Let's say that the charge will be varied +/- 1 grain in half grain steps. Powder A at 92.0, 92.5, 93.0. 93.5, 94; and Powder B at 6.5, 7.0, 7.5, 8.0, 8.5.
Let's say that there are two bullets, Bullet #1 and Bullet #2.

We have 10 powder choices with two bullets, 10 X 2 = 20 tests that must be shot. If we are to shoot one five shot group with each combination, then there 20 X 5 = 100 shots required.
Add a third powder, 5 more choices, and we need 500 shots, when one five shot group is the test. If five five shot groups are required, we need 2500 shots with two powders, 5000 shots with three powders.
Now one five shot group doesn't tell us much.
For instance, on 9/26/07 with the amazing IMR4198, groups were 1", 1.15", 1.6", .575", .85", averaging 1.035". If only one group was shot, if it was 1.6", my reaction would be different than if it were .575". Groups vary too much for one to count for much.
Now we can got to fewer groups or groups with less shots, or we can maybe do something clever.
In the book, Cast Bullets For Beginner And Expert, Second Edition; (which is written and done and being printed and mailed right now,) at http://sports.groups.yahoo.com/group/CB-BOOK/, in "Files", 6.6 HOW TO WORK UP AN ACCURATE RIFLE LOAD, WORKING UP A CAST BULLET LOAD
By Jesse Miller OD. CBA Competitor, there's a description of Jesse's "TIC-TAC-TOE Chart, and how to test more with less. (This thing and others I'm working on now is for the Third Edition, ERRATA for now. Second edition = done, Third edition = in process)
Back to two powders, five charges each, and two bullets. Conventionally we'd need 10 X 2 = 20 tests.
Using Jesse's method, we might test as follows:







Test # Powder Charge Bullet
1 A 92.0 #1
2 A 92.5 #2
3 A 93.0 #1
4 A 93.5 #2
5 A 94.0 #1
6 B 6.5 #2
7 B 7.0 #1
8 B 7.5 #2
9 B 8.0 #1
10 B 8.5 #2

We're testing both powders, all charges of each, both bullets-but not all possible combinations. Jesse's method implies that if there is a difference in accuracy between Bullet #1 and Bullet #2, that that difference is (somewhat) independent of the powder charge.
And we've halved the number of tests required.
We could further reduce the number of tests by eliminating some of the powder charges, thus:

Test # Powder Charge Bullet
1 A 92.0 #1
3 A 93.0 #2
5 A 94.0 #1
6 B 6.5 #2
8 B 7.5 #1
10 B 8.5 #2

Now we're down to 6 tests. At 25 shots per test, 150 shots for group. At two five shot groups per test, total 60 shots for group.

Something like this, using Jesse's method and reducing the numbers of shots per test, must be done to keep the volume of shots bearable.
Imagine that we've shot the two groups per test, measured the groups, computed the averages, and get this:

Test # Powder Charge Bullet Group Average, "
1 A 92.0 #1 1.3
3 A 93.0 #2 1.5
5 A 94.0 #1 1.2
6 B 6.5 #2 1.8
8 B 7.5 #1 1.6
10 B 8.5 #2 1.4

Powder A 1.3 + 1.5 + 1.2 = 4.0/3 = 1.33 avg.
Powder B 1.8 + 1.6 + 1.4 = 4.8/3 = 1.6 avg.
Powder A wins.
Bullet #1 1.3 + 1.2 + 1.6 = 4.1/3 =1.275
Bullet #2 1.5 + 1.8 + 1.4 = 4.7/3 = 1.433

Bullet #1 wins

So, time for more testing. Let's try Powder A and Bullet #1, the best charge looks around 94.0 grains, so let's try 93.5, 94.0 and 94.5.

This ain't easy, and it is searching around with small numbers, but it may just serve to direct us toward the most accurate load. It is, however, better than stumbling around blindly, which I now see myself doing in the past.
joe brennan

[leftiye]

Pat, Good on ya! You seem willing to bite your tongue when others aren't. I fortunately am not yet a guru, therefore I have no ego to promote. As for listening, we ALL are and have been listening for a long time, and have yet to hear anything warranting the effort. Must all be subhuman and not able to understand (Don't bet the farm on it).

Joe, My guess is that we'd all like to finally have the answers to the question of accuracy. But as we are seeing, even the git go is somewhat complicated. It seems to me that even at the start there is a range of possibilities depending on what your situation is as per gun/load etc. that determins the first step in improving, and at each phase thereafter you are again faced with multiple choices as to what approach to follow in your effort to improve on what has been done. Being a good diagnostician is the esence of it all.

Conversely any wise person will try to follow the "guidelines" in getting started. That is in setting up the gun to comply with known principles of accuracy (including choosing a gun that is manufactured in accordance with best concepts), and following good reloading principles as concerns accuracy, and then shooting from a rest situation that gives the best results.

[Char-Gar]

What a shame... These threads which hold the potential to be very helpful, so often turn into pissing matches.

[Pat I.]

What's the shame is the tolerance level allowed the abusive or sarcastic behaviour by the self appointed "Experts" on internet forums. What should happen is you get on here and state your case expecting questions. If it's something out of the norm when questioned explain what you did in plain language expecting more questions until everyone's questioned out.

If you ask a question don't immediately go on the attack if the answers you get don't conform to your preconceived notions or for some reason you just don't like them. Saying "your methods or alloy just aren't up to", "you wouldn't understand" or some other such crap isn't an answer it's a dodge and immediately sends my BS detector to full alert. If I write something and someone asks about it I'll answer to the best of my ability in a civil way and if I don't know the answer I'll say so. If I ask a question about something written I expect a civil direct to the point answer and refuse to roll over and play dead if I think there might be a little keyboard enhancement going on because I'm a new poster or not part of the "In Crowd". I apologized twice in a different topic for getting into a pissing contest, something which I noticed the opposing pissee didn't bother to do, but I don't think I'll make that mistake again.

Since I've never found a correlation between bold font and knowing what you're talking about I'll continue to question things I might find a little off kilter and answer things when I feel I might be able to add a little light.

[joeb33050]

There's a lot of words that I wrote here, but I think that the outline is understandable. There's a lot of words that others wrote here, but I'm not getting much help. Surely I can't be RIGHT!!! on all this stuff. Surely there are those out there who know that and where I'm wrong.
The original premise of all this writing was that BETWEEN US we have a lot of knowledge about cast bullets, and WE, working together, can distill it all down. You/we have 496 pages done, with a lot of dissenting opinion. Look at this, find out where I went astray, limber up those fingers and set me straight. Or, ask questions when it's not clear. But do something, this is an important topic, one that the newcomer needs to have laid out for him-one that I need laid out for me. Don't be shy, hammer this thing out!! Where are Felix and Bass Ackwards and Junior D. when we need you?
Thanks in advance
joe brennan

[Ricochet]

Joe, I'd be glad to help, but I'm still learning this stuff myself! I've had some pretty good successes and figured out how to fix problems I had, but to come up with a general protocol is a tall order and certainly far beyond my abilities.

I share the frustration with "experts" who speak like Delphic oracles.

[Char-Gar]

Joe et al.... I am not the science type, but I have my own way of searching for accuracy with a particular rifle.

The first step is trying to eliminate as many variables as possible, by using some standards that I know work for me.

I start with a bullet that fits throat, lands and grooves from No. 2 Alloy.

I start with a Remington 9.5 Primer because experience has shown me I can find the sweet spot more often with this primer than others.

I start with 2400 powder at a velocity of about 1.5 K fps.

Of course, I want the rifle to have all screws tight, bedded right, and with good sights. The rifles is held properly and the basics of riflecraft are followed. The cases are fire formed to the chamber, neck sized, and ammo all straight and concentric.

When I have jacked with the 2400 powder charge until I get the best groups, I will then try a different powder. The velocity range will depend on the powder. I keep all of the others variables as my standards. Slower powder do best when you move beyond the 1.7 - 1.8 K fps rang.

When I have found the powder and load that seems to do best, I can then change one more variable, such as Primer. When I see what the primer change will do to my groups and will tweak the powder charge a mite.

Then might be time to change one more variable, such as alloy or sizing diameter, but only one change at at time.

I only change one variable at a time, and try to follow a linear path. I suppose a fellow could test and test and test until he is old and grey and never exhaust all of the possible variable, but I doubt if much is to be gained with protracted testing.

If I can't get a rifle to shoot with my standard components, it ain't going to shoot. It may not produce the very best accuarcy, but it will produce good accuracy. Tweaking might drop the group size 1/2 MOA or so, but it won't turn a pattern into a group.

Back in the late 50's and early 60's when I was shooting competition high power (non service rifle), all of us knew if a 30-06 rifle would not shoot good with 52/4350/180 match bullet it would not shoot. This was what is called today a "cookbook" load. That is where we started in the search for accuracy when the blue chips were down. A rifle that would not do well with the above load was sold down river and no further time and energy were spent fooling with it. Time was best spent on the range, honing our shooting skills than endless tinkering with the load.

The cups, ribbon and trophys were brought home with a good rifle, a good load, and most important a good shooter.

I don't buy this business that cast bullet shooting is so esoteric that accuracy is akin to voodoo charms. Cast bullets do introduce more variable than comdom bullet shooting, but that is what makes it so interesting. But I firmly believe the average joe can get high grade cast bullet accuracy out of his rifle by following basic principals along a linear path.

[KYCaster]

Joe: Way back in the dim past, someone here(I don't recall who) described a method of determining the optimum powder charge for a bullet. I'll see if I can describe it clearly.

Start with the manufacturer's recommended charge wt. for the bullet you're using. Load one round each beginning with the start wt. and increasing in increments of one grain(or .5 or .1 ....depends) until you reach the recommended max wt. You should have ~10 or so loads with the only variable being the powder wt.

Shoot these from a rest beginning with the lowest and progressing to the max or until you encounter pressure signs. You should end up with a vertical string with hits rising on the target as powder wt.(and velocity) increases. There should be some number of hits that will be obviously closer together than the others in the string, often three or four in a fairly tight cluster. These hits will be at or near the optimum charge wt. for that powder.

You can then repeat the test using the median of the closest hits and test with smaller increments below and above this wt.

I've tried it a couple of times and it seemed to work as described....thing is you have to have confidence in your platform(as Bret calls it), your bench technique...etc. It is recommended that you shoot at least 200yds. and better yet 300 so the greater dispersion will make it easier to find the "sweet spot". Trouble is, some of us have a hard time hitting anything at 50.:oops:

Hope this is the kind of thing you're looking for.

Jerry

[leftiye]

I don't know if this helps or hurts. The first step may be- what do I want to do? Nothing at all to do with a gun, accuracy, anything else. Okay, I want to shoot ground squirrels at 200 yards with a cast boolit load. Any problem? No, it can be done. Second step, what cartridge do you want to use? Probably one I've already got a gun for. How much power is needed? Not much, hit them right, they die. Anyway you make a choice. Now you look at the gun, is it going to work as desired or should I modify it or work on something about it? And you make a choice.

Then you start researching available boolits and molds. And you make a choice. when you've decided on a boolit, you start looking at loads. With Jacketed bullets I always looked up the fastest loads. Then I worked up pressure tests to see which loads actually COULD be used and which were hot air. Once this was done I shot these near max loads and saw which were most accurate. This gave me a place to start tweaking for accuracy. (these were hunting loads, not make holes in paper loads) And you make a choice, each choice starts the next phase.

[MT Gianni]

Joe, I never work with 2 bullets. I pick one that I think should shoot based on diameter and seating depth. I then research various recommended powders and see what turns up the most. I then vary loads with 1 powder and measure results. I next try a different powder until I find something acceptable. I move to another bullet next. 1 bullet, 1 powder each range trip. It may help that I've never been more than 20 minutes from a range. Gianni

[Buckshot]

.............Joe, I believe I've read all the thread and what it is you're wanting to accomplish. In your first post, you said:

"This experience opened my eyes to the fact that my search for accuracy was not well organized and that I've never read of an accuracy search procedure.

I may be a bit simple minded, but I'm thinking that what you're wanting to do is to provide a chart or list of a reasonable progression through various accuracy enhancing steps a person might follow?

Am I right?

................Buckshot

[45 2.1]

"This experience opened my eyes to the fact that my search for accuracy was not well organized and that I've never read of an accuracy search procedure.

The foremost thing you can do to get accuracy is fitting the boolit to the chambers neck, throat and bore. Until you do this, you wll have all the secondary factors you've mentioned.

[joeb33050]

.............Joe, I believe I've read all the thread and what it is you're wanting to accomplish. In your first post, you said:

"This experience opened my eyes to the fact that my search for accuracy was not well organized and that I've never read of an accuracy search procedure.

I may be a bit simple minded, but I'm thinking that what you're wanting to do is to provide a chart or list of a reasonable progression through various accuracy enhancing steps a person might follow?

Am I right?

................Buckshot

Absolutely. WHAT to do when is the question, HOW is covered elsewhere.
joe b.

[Bass Ackward]

I hope you don't think I'm calling you or anyone else a liar because I'm not but what some say sometimes is in direct conflict with what I've found so I'm going to question it.


Pat,

I am not offended. But if a fella says that he'd have to see that for himself, that is a whole lot different from asking how it was achieved. Because I could show you that it can be done, and you still wouldn't know how to do it.

I just am frustrated as to WHY others can't do it. So I took some time away from here and decided to think about why " I " am able to do it when others can't can't. The answer is just the very reason Joe's list is meaningless. Different goals for cast require a different lists. A fella shooting soft bullets for hunting has a different accuracy agenda and list than someone with the luxury of hardening his bullets. And there are three ways to shoot cast. Shooting cast like cast at what is commonly known as cast velocities. Shooting cast at low pressures for higher velocity. Or trying to harden cast and trying to shoot cast like jacketed until RPMs get ya and the lead craps. The REAL PROBLEM is that people go from method one to method three too fast!!!

I am going to start another thread even though it will dramatically affect Joe's list. Joe's list that he wants to develop is affected by the thought processes people have to shooting cast, not with any, logical, methodical, or scientific work flow pattern to achieve accuracy. Because of this, no list is going to make sence to everybody or anybody.

[joeb33050]

Now we're starting to make some money. I'm going to address each comment, may not refer to the commenter by name. If I missed a point, let me know.

What we're doing applies to bolt action and single shot rifles with adequate sights. I categorize accuracy here as >2", 2"-1.5", 1.5"-1" and <1". These guns will operate in (some of) these ranges under the conditions stated. I don't know about lever, pump or autoload guns. I don't know how to deal with military rifles with issue sights. The 03A3 is about the only military rifle with a peep near the shooter's eye, and has a blade front. Old people in particular can't shoot 03 Springfield or Mauser guns accurately enough to operate in the >1.5" range even if the rifle is capable.

The objective is a rational accuracy search procedure.

Cookbook loads. The original name of the book included the word "cookbook", and the book has a part called "Cookbook loads that work in any gun". I believe that these loads may not be the most accurate, but will be pretty accurate, and if they ain't accurate there could very well be trouble with the rifle. I also believe that this load development business is not witchcraft, it isn't that hard.

Starting point. Yes, the bullet should fit the gun. We should start with a recognized or cookbook load. Research will help find a starting point.

Chargar has a favorite powder and primer. This is in the cookbook area. He wants the rifle "right". WE NEED more on getting the rifle right, screws, bedding, etc. He wants ctgs straight and concentric. Nice if you've got the setup, but not needed at first??
Then he's linear, one change at a time.
MTGiannji is linear, one change at a time

KYcaster describes "ladder testing", there's an article in the book. It works for me, but doesn't address THE question, does address A question. The practical problem is that half grain changes in powder charges over a ~6 step range don't change elevation much at 100 yards, hence the need for greater range.
That that I wrote doesn't make sense. Another try.
If, after getting rifle and equipment right and powder/bullet/primer/OAL/powder selected; we could ladder test the powder-in half grain increments. Ex: 30/30, 31141, WLP, 2.840", IMR4198. Load one each at 18, 18.5, 19, 19.5, 20, 20.5. Shoot and watch them march up the paper, see where elevation doesn't change much, that's about where the best charge is.
I THINK that at 100 yards the elevation doesn't change enough to show up, but I may be wrong. I'll try it Wednesday. This could be a breakthrough!! I hope so.

So, where are we?
We need something on getting the rifle, scope, bench rest and bench "right", the conditions required.

We don't have disagreement about "change powder, charge, bullet and get from 2" to 1 1/2", except for Chargar's "straight and concentric", which I think comes later.

And we've got the "linear, one change at a time" approach. That's where I started, and I want to find a better = less time and component consuming method. Maybe that ladder testing.

I'm working on it. Anyone else willing to do the "ladder testing" test with a known accurate load at 100 yards? Or even/both 200 yards?

Thanks, keep it coming;
joe b.

[Char-Gar]

Joe.... I guess folks could disagree if accuracy starts with a rifle that is "right" or a load that is "right". But, IMHO the rifle is the place to start. If the rifle is not right, trying to find the most accurate load lis like a dog chasing it's tail.

Now confession time: I truly enjoy building rifles and building them right. When I build a rifle I test it through the process with full snort condom loads. I do this for two reasons;

1) Accurate condom loads are easier to find that accurate cast loads. Most often quality factory ammo is used.

2) If a rifle will handle the recoil and bounce of full snort comdom ammo and deliver good accuracy, it will also deliver the same or better accuracy with cast loads.. The comdom loads puts the bedding to the test in a way the cast does not. You will also find sight problems quicker.

Once the rifle is shooting the way I want, I clean out the copper and it is cast from then on out. I have yet to build or tweak a rifle to shoot well with comdom ammo that did not deliver equal or better accuracy with cast.

I think Bass is correct, that cast accuracy has allot to do with your goals. You need to have a clear idea of what you want to do, and them follow the path to that goal. I would this this is a given and should be understood by anybody taking up the lead dipper. You must know where you want to go in order to get there.

But 4.5 2.1 is also correct that bullet fit is the starting place for whatever goal you choose. Whatever the goal, things go better when the bullet is introduced into the rifling straight and wobble free. Fast, medium or slow velocity ...soft, medium or hard alloy ..bullet fit is where it starts down the path for accuracy. The other variable may.... well..vary...but bullet fit is "Go" on the accuracy board..

[Pat I.]

BA,

This will be the last thing I post In this thread because I think we've interrupted enough.

I'll be happy to participate in any thread you start IF things are explained in a reasonable and timely fashion, IF the BS about people not being able to understand what's being discussed is left out, and IF opposing opinions and results are able to be given without it turning into a pissing contest.

Agreed that telling and showing are two different things but if I could do something that 90% of the people said couldn't be done I'd be chomping at the bit to actually prove it. Personally I don't think shooting cast bullets accurately is some deep dark secret only achievable by a select few so a simple explanation will be more than sufficient for most people with a little more thrown in if there's an additional question or two.

[MT Gianni]

Joe, My reason for linear testing is that trying any other method so far has skipped useful info to me. Gianni

[PatMarlin]

For cryin' our loud...

You're asking for step by step instructions, that can whittled down for cast shooting from a subject that has taken up years of posts here at Cast Boolits. Your gonna need more patience with this one grasshopper.. :mrgreen:

[PatMarlin]

I think one structure that would be incredably helpful would be real life "Case Study" examples.

For instance following the proceedures of a particular rifle or handgun like... how BassAckward acheived accuracy with the "35 Whelen Bolt Rifle".

Or- How Charles Chargar found cast boolit heaven with his "Model 70's".

There are to many varibles to pin it down to comform to steps 123 in this game, but a caster could see what one guy did and got the desired result, and apply it to his simular firearm which is after all what the Cast Boolits Forum is all about.

Pick examples of the best and the brightest.

[joeb33050]

I think one structure that would be incredably helpful would be real life "Case Study" examples.

For instance following the proceedures of a particular rifle or handgun like... how BassAckward acheived accuracy with the "35 Whelen Bolt Rifle".

Or- How Charles Chargar found cast boolit heaven with his "Model 70's".

There are to many varibles to pin it down to comform to steps 123 in this game, but a caster could see what one guy did and got the desired result, and apply it to his simular firearm which is after all what the Cast Boolits Forum is all about.

Pick examples of the best and the brightest.

I'd like to see some of those case studies, however, "There are to many varibles to pin it down to comform to steps 123 in this game" is not true, in my opinion. Thinmk about it.
joe b.

[joeb33050]

Joe, My reason for linear testing is that trying any other method so far has skipped useful info to me. Gianni

Please elaborate, tell us more, with maybe some examples.
Thanks;
joe b.

[joeb33050]

Joe.... I guess folks could disagree if accuracy starts with a rifle that is "right" or a load that is "right". But, IMHO the rifle is the place to start. If the rifle is not right, trying to find the most accurate load lis like a dog chasing it's tail.



Most of us don't build rifles, so we end up with a rifle either stock or custom.
Certainly things need to be done to a new-to-me rifle before shooting cast bullets. What are these things? Not involving machine work, things the average joe can and should do.
How about writing here on that?
Thanks;
joe b.

[joeb33050]

I get good accuracy with 19.5/IMR4198.
I made up three sets for ladder testing, 18, 18.5, 19, 19.5, 20, 20.5, 21--this gives me three charges either side of the 19.5. I'll shoot these Wednesday to see what happens at 100 yards, which is all the range I've got.
How about some of you guys trying some ladder testing?
Thanks;
joe b.

[Char-Gar]

Joe... I think the aspects of a rifle that need attention are well known. They would be

1) The bedding or the marriage of the stock and the metal. You don't want any looseness that will allow the metal to shift in the wood druring recoil. You want the fit to be uniform so there will not be a twisting or bending of the metal. The barrel also needs the freedom to vibrate according to it's own wishes.

The well known glass/gel bedding compound is a common fitxfor these problems. The use of metal pillars on which to rest the bottom of a round action are also popular.

2) The sights must be installed properly and on tight. Scopes bases and rings should be concentric and level so there will be no bending of the scope.

Iron/receivere sights need to be visable and provide for a good sight picture. The flat top post or globe front sights seem to fill the needs of most folks.

3) The barrel crown is a very key part of an accurate rifle. The crown needs to be eve and at a 90 degree angle to the bore. When the bullet escapes the barrel, gas under pressure shoots out around the bullet base. These gases need an even and square surface to push against so the bullet is not shoved one way or another.

4) Laping the bolt bearing surfaces for an even and full fit in the receiver can also be an accuracy booster.

There are many other things than can be done, but you said no machime work. It can be argued that a recrowning is machine work, and so it can be. However is so important that it needs to be included in any list of basics.

[HORNET]

Joe,
Just a couple of comments.
1. Jesse's Tic-Tac-Toe chart should work fine - if you can keep track of the analysis. Its a basic testing pattern from Design-of-Experimentation theory and is intended to provide maximum return for minimum input. The only problem is the data analysis, which confuses people that haven't learned to sort out the results (and some that have:???:). That is the reason most people use linear testing.
2. The 1/2 grain steps are not necessarily appropriate in all cases. I saw in the Accurate Arms Loading manual that they recommend reducing the load 10% and working back up in 2% steps. This makes much more sense than using the same size steps for a wide range of nominal charge weights. I've been doing about the same thing for years and thought that it was really great to have them agree until I found the same advice in a Belding & Mull Handbook from the 50's...[smilie=1:

[joeb33050]

Joe,
Just a couple of comments.
1. Jesse's Tic-Tac-Toe chart should work fine - if you can keep track of the analysis. Its a basic testing pattern from Design-of-Experimentation theory and is intended to provide maximum return for minimum input. The only problem is the data analysis, which confuses people that haven't learned to sort out the results (and some that have:???:). That is the reason most people use linear testing.
2. The 1/2 grain steps are not necessarily appropriate in all cases. I saw in the Accurate Arms Loading manual that they recommend reducing the load 10% and working back up in 2% steps. This makes much more sense than using the same size steps for a wide range of nominal charge weights. I've been doing about the same thing for years and thought that it was really great to have them agree until I found the same advice in a Belding & Mull Handbook from the 50's...[smilie=1:

Rick;
I will add your 2. to the article. I'm working on making the 1 easier.
Thanks;
joe brennan

[joeb33050]

This whole thing is about WHEN to do what. Do we do XX First, before shooting, or when we are trying to get groups under 1", or when there's horizontal dispersion, or WHEN

Bedding: WHEN do we do this? What is the signal that something needs to be done?

Looseness: All screws tight, can be done FIRST. However, stories abound about "tighten this one and loosen that one a little and it shoots better".

Free floating barrel: Again, WHEN. Many older rifles are stocked tight, free-floating wopuld change the look of the rifle to the worse. How about those cardboard shims we use?

Sights tight and proper. Scope bases and rings? lapping in requires some skill and equipment. I vote for Burris can't-remember-the-name rings tha have plastic inserts that rotate and linje things up.

Iron sights-ok

Crowning: WHEN?? I look and if there's nothing obvious, leave it alone. There's an article on how to crown a rifle barrel at home, if you MUST and can't get a gunsmith to do it. It's a last resort measure, in my mind. I've done it ~10 times, always worked fine, but... Also see "Damaged Bullets" about that uneven gas business.

Lapping the bolt bearing surfaces: When is it needed, what's the sign? I've done this in the kitchen, not hard, but did it ever change my life? Nope. Anyone know of it changing things a lot?

Anyhow, more info is needed, particularly about the WHEN of these, and maybe others.

Thanks;
joe b.


Joe... I think the aspects of a rifle that need attention are well known. They would be

1) The bedding or the marriage of the stock and the metal. You don't want any looseness that will allow the metal to shift in the wood druring recoil. You want the fit to be uniform so there will not be a twisting or bending of the metal. The barrel also needs the freedom to vibrate according to it's own wishes.

The well known glass/gel bedding compound is a common fitxfor these problems. The use of metal pillars on which to rest the bottom of a round action are also popular.

2) The sights must be installed properly and on tight. Scopes bases and rings should be concentric and level so there will be no bending of the scope.

Iron/receivere sights need to be visable and provide for a good sight picture. The flat top post or globe front sights seem to fill the needs of most folks.

3) The barrel crown is a very key part of an accurate rifle. The crown needs to be eve and at a 90 degree angle to the bore. When the bullet escapes the barrel, gas under pressure shoots out around the bullet base. These gases need an even and square surface to push against so the bullet is not shoved one way or another.

4) Laping the bolt bearing surfaces for an even and full fit in the receiver can also be an accuracy booster.

There are many other things than can be done, but you said no machime work. It can be argued that a recrowning is machine work, and so it can be. However is so important that it needs to be included in any list of basics.

[joeb33050]

For cryin' our loud...

You're asking for step by step instructions, that can whittled down for cast shooting from a subject that has taken up years of posts here at Cast Boolits. Your gonna need more patience with this one grasshopper.. :mrgreen:

You've got it, by thunder! We must know how to do this, after all those posts! (I don't flux while casting.)
joe b.

[Char-Gar]

Joe... If a rifle shoots better with a screw backed off that is a clear sight of a problem. There is situation where the action is being bend, twisted and/or the barrel jamed down into the wood in the wrong way. The problem needs to be chased down and located. Then corrected with bedding compound so the screw can be cinched down and the acton and barrel will be in proper alighment.

Now I am talking about acton screws here. Barrel band, barrel retaining screws and others things that hold on the barrel are different matters.

[joeb33050]

We were enjoying the end of a hurricane Wednesday, so I went to the range yesterday. I wish I could take better pictures.
Here's the target. Yesterday was the first time in my memory that a primer didn't set the charge off-yes, there was powder in the case. 100 Yards
joe b.

[joeb33050]

I get good accuracy with 19.5/IMR4198.
I made up three sets for ladder testing, 18, 18.5, 19, 19.5, 20, 20.5, 21--this gives me three charges either side of the 19.5. I'll shoot these Wednesday to see what happens at 100 yards, which is all the range I've got.
How about some of you guys trying some ladder testing?
Thanks;
joe b.


Here's a better picture of the ladder test. Loring Hall advised me lon ago to take the targess home, let them cook, then examine them. It took me two days to find the pattern here. More tests Wed.
joe b.

[joeb33050]

Here's a better picture of the ladder test. Loring Hall advised me lon ago to take the targess home, let them cook, then examine them. It took me two days to find the pattern here. More tests Wed.
joe b.

Another try

[Sailman]

Joe

I have been shooting lead bullets since apx. 1955. Just like any one else, you develop your own system of trying to obtain accuracy. The system you develop may or may not agree with other people. However, over a period of years, one does come up with a system that works for yourself. The following are things that have worked for me:

What bullet size works for a certain rifle.
As an example, if the rifle I am going to be testing is a 30-06, to find out what bullet
size works best in that rifle, I will take a given proven load from another 30-06 and use
that power and charge. I will size 10 bullets .308, .309, and .310. What ever size gave
the smallest group will be the size that rifle will shoot with that bullet ( I have had
occasions where different bullets require a different size than the standard size that
rifle wants to shoot ). I will repeat this test again. After two tests if the results are the
same, I assume that the bullet size has been established for that bullet in that rifle.

Bullet seating depth.
I have over the years been satisified with seating the bullet as far out as possible, just
short of tuching the lands and groves. Once I estiblished the seating depth, I make a
seating gauge for that bullet. I seat a bullet in a case ( the primer pocket has been
drilled out ). I mark a number on that case and record the bullet number on a piece of
paper ( example # 4 = 311291 ). I have small containers for each rifle and store all
the bullet seating gauges for that rifle in that container.

Distance
All my testing is done at 100 yds.


Powder charges
When trying to establish what powder charge works best, I test charges progressively.
As an example, I am currently testing bullet 311291 with 2400 powder in my Savage
308 rifle. I start out by loading 10 rounds each with 15, 16, 17, 18, 19, and 20 grs. I
will repeat that test again. After two tests, I will select the three best charges. As an
example 16, 17, & 18 grs. I will then test 10 rounds each with 16, 16 1/2, 17,17 1/2,
18, and 18 1/2 grains. I will then do that test again. I will then select the three best
charge groups. I will test the three best groups, as an example, 17, 17 1/2, and 18gr
with 20 shot groups. I will repeat the 17,17 1/2, 18gr 20 shot group test again. By this
time, I will have reasonably good confidence that the charge I have selected is the charge
required for best accuracy.


I think that most people do not consider the effect of basic statistics when establishing the group size for testing. THE LARGER THE SAMPLE SIZE, THE MORE ACCURATE WILL BE THE PREDICTION. In my opinion, 5 shot groups will NOT give you an accurate estimate of your predicted group size. 10 shot groups will put you in the ball park. 20 shot groups will provide a much better prediction. However, you should shoot more than one or two 20 shot groups to establish what size that load will shoot. Even with multiple 20 shot groups there is the chance of error. As an example, on the 24th of Oct. I shot a 10 shot group using 311291 with 17 1/2 gr of 2400 that measured 1 5/8 in. On the 31 of Oct I shot a 20 shot group with the same load that measured 2 5/8 inch. I have more faith in the 2 5/8 results. Tomorrow I am going to shoot another 20 shot group for 17, 17 1/2, and 18 grains of 2400. After tomorrow I should have a reasonable estimate of the accuracy of the 17 1/2 gr. load.

What is an accurate load.
When shooting a 20 shot group, if you can consistently get 2 1/2 inch groups at 100 yds, I would say that is very acceptable. Yes, you will get smaller groups at times, however, 2 1/2 inch groups is about all you can expect for a 20 shot group.

I know that many folks feel that a 2 1/2 inch group at 100 yds is not all that impressive, but, when shooting a 20 shot group you will get a much better idea what your rifle will do with that particular load. It is nothing more that basic statistics.

Joe, a quick unrelated question. In 1990, four of us sailed a boat form St. Thomas to Clear Lake Texas. We stopped at Marathon for two days. From the little knowledge I got from that visit, my question is where is the range you do you shooting?

Sailman

[Bass Ackward]

What is an accurate load.
When shooting a 20 shot group, if you can consistently get 2 1/2 inch groups at 100 yds, I would say that is very acceptable. Yes, you will get smaller groups at times, however, 2 1/2 inch groups is about all you can expect for a 20 shot group.

I know that many folks feel that a 2 1/2 inch group at 100 yds is not all that impressive, but, when shooting a 20 shot group you will get a much better idea what your rifle will do with that particular load. It is nothing more that basic statistics.
Sailman


Not to pick on Sailman, but take a test.

Shoot 20 shots of 22LR ammunition at 50 feet and then grab a 460 WBY and shoot 20 shots at 50 feet. Which rifle was more accurate? Is the test of the accuracy of the gun, the load, or simply a statistical analysis of you?

Concentration and focus only last so long. And it varies for everybody. Then you have other factors like barrel fouling and temperature that affect cast accuracy. One may argue that accuracy is what it is, and if that is your criteria there isn't a person that can argue with you. But it is your accuracy, not anyone else's.

If you develop a load that fouls in 20 shots or cast bad bullets and finally get a .... statistical flier, is that the accuracy potential of the gun? How many guys you see shooting cast bullet bench rest over 30 caliber? How many believe that best cast bullet accuracy comes at low recoiling levels or low velocity or .... low RPMs? :grin:

Accuracy has many definitions. You must pick the one that's right for you. So if you can't define the criteria, you can develop method.

[joeb33050]

Joe



THE LARGER THE SAMPLE SIZE, THE MORE ACCURATE WILL BE THE PREDICTION. In my opinion, 5 shot groups will NOT give you an accurate estimate of your predicted group size. 10 shot groups will put you in the ball park. 20 shot groups will provide a much better prediction. However, you should shoot more than one or two 20 shot groups to establish what size that load will shoot. Even with multiple 20 shot groups there is the chance of error. As an example, on the 24th of Oct. I shot a 10 shot group using 311291 with 17 1/2 gr of 2400 that measured 1 5/8 in. On the 31 of Oct I shot a 20 shot group with the same load that measured 2 5/8 inch. I have more faith in the 2 5/8 results. Tomorrow I am going to shoot another 20 shot group for 17, 17 1/2, and 18 grains of 2400. After tomorrow I should have a reasonable estimate of the accuracy of the 17 1/2 gr. load.


Joe, a quick unrelated question. In 1990, four of us sailed a boat form St. Thomas to Clear Lake Texas. We stopped at Marathon for two days. From the little knowledge I got from that visit, my question is where is the range you do you shooting?

Sailman

Each bullet hole has a quantity of information about it. Then 10 shots or 20 shots or 500 shots contain a quantum of information.
There is a clear and simple relationship between group size as the number of shots in the group changes. More shots, larger group. So, a 13 shot group is zz times as large as an 8 shot group.
Simple, easy, and not helpful.
Brent Danielson is an exponent of the 2 shot group, and has a lot of good reasons for using 2 shot groups.
I like 5 shot groups, for the best reasons.
Others like 10 shot groups.
Nobody else I know likes 20 shot groups.
Remember, if you and Brent and I go to the range and shoot a load, 50 shots-the amount of information in those 50 holes is the same no matter the size of the series.
I've given a lot of thought to the matter, and use sets of 5 shot groups.
Here are some reasons:
5 shot groups are popular, frequently reported, thus we have some idea of what is "normal" or expected. Not so with the 7 shot group.
>5 shot groupss increases the chance of a "honker", diminishing the value of the info in the other shots.
Changing aiming point changes POI, the amount has to do with the bench rest used. This is my big argument against the 2 shot group.
I can comfortably shoot 3 sets of five, five shot groups in a day. I shoot experiments every range day, so the 3 sets are 3 loads. I'm not comfortable with sets of 10 shot groups

So, I shoot 5 shot groups, and base all my stuff on that fact. 5 ain't "right", nor is 2 or 10 or 3. Pick one and have at it. There's no statistical or practical argument for any group shot number, 2 or 5 or 29, that I've ever seen.

The nearest decent range is in Miami, just exactly 100 miles from home. I go most every Wed., generally on the motorcycle.

joe b.

[HORNET]

FWIW, I use 3 shot groups for initial testing to get the most loads out of a batch of cases. The most promising load ranges, based on the 3 shot groups, get loaded into 5 shot batches, breaking the range into smaller increments. Picture, say 1 grain steps for the 3 shotters and 0.5 grain steps for the 5 shot groups. I have been known to use 35 yards (just to be sure to hit the paper) for the 3 shot groups and 50 yards for the 5 shot. I may do a slight shift and retest the 5 shot batches at 50 yards a couple more times, and maybe with smaller increments, if the results indicate that things are wierd. 50 yards is also a lot easier to walk than 100 for some reason:roll:. When 50 yard results seem stable,or if its hard to tell which load is doing better, and the stinkin wind cooperates, I then go to 100 yards, initially with 5 shot, then with 10. I don't trust much until I get very good results with the same load on 3 separate days.... I've got a lot of loads waiting for the stinkin' wind to back down but deer season starts soon[smilie=1:....I also shoot lots of 4 shot groups out of the Hornet, my styrofoam block holds 10 rows of 4 and 4 shot groups really annoy people :-D.

[joeb33050]

Ladder Testing To Date, 11/8/07

Attached, perhaps, is the 7/11/07 ladder testing target. This is with 31141, 100 yards, IMR4198. The bullet holes are numbered. 1 = 18 gr., 2 = 18.5, 3 = 19, 4 = 19.5, 5 = 20, 6 = 20.5, 7 = 21, 8 = 21.5, 9 = 22, 10 = 22.5.
Ladder testing is a method of quick and easy and not-many-shots getting a clue about which of a series of powder charges might be found to be the most accurate. It isn't and never was touted to be the secret to accuracy testing, and it won't make your hair grow back.
The theory behind ladder testing is that as powder charges are increased, bullet hole impact rises. Then, around the best charge, over some few increasing charges, elevation doesn't change (much). Then, still increasing the charge, elevation continues up.
The object of this exercise is to see if ladder testing with cast bullets at 100 yards works-will it give us that clue about where on the scale of powder charges we should look for best accuracy?
As you can see, we've got 30 holes in the paper, in ten sets. Perusal of the target and much thinking may get us to some conclusions, but I think analysis is better.
We're looking for a series of consecutively made holes where the elevation doesn't change much. We don't care if hole 1 is close in elevation to hole 10, or to hole 3. So the questions are, Is the elevation of hole 2 about equal to the elevation of hole 1? Code the question to Is #2 E ~ = #1 E?. Then, since there are 10 holes/loads, there are 9 questions, ending with Is #10 E ~ = #9 E?
Put the questions in a column, put the answers for the first, second and third targets in adjacent columns. Here's what I got.

11/7/2007 11/7/2007 11/7/2007 IMR4198
First Second Third Grains
Is #2 E ~ = #1E? No Yes No 18
Is #3 E ~ = #2E? No No Yes 18.5
Is #4 E ~ = #3E? Yes Yes No 19
Is #5 E ~ = #4E? Yes Yes Yes 19.5
Is #6 E ~ = #5E? Yes Yes Yes 20
Is #7 E ~ = #6E? Yes No No 20.5
Is #8 E ~ = #7E? No No No 21
Is #9 E ~ = #8E? Yes No Yes 21.5
Is #10 E ~ = #9E? No Yes No 22

We're looking for clumps of adjacent Yes answers. It's clear to me that the Yes answers clump about #3 to #6, about charges from 19 to 20.5 grains of IMR4198.

Are the Yes/No answers subjective?
Yes.
Why did I do 3 tests?
Because I don't believe much of any conclusion from a single test. More data is more better, and in this case doesn't cost much time or money.
What should the shooter experimenter do next?
Load some cartridges with each of the charges, and test for group size.
What do we know about ladder testing at 100 yards with cast bullets?
At this point it looks like ladder testing may give us a clue about the powder charges to concentrate on in accuracy testing.
How can we be more sure about ladder testing?
Do some more tests. Take a known good/best powder charge, EX: 28 gr.. Select a set of safe loads around that load, EX: 25.5, 26, 26.5, 27, 27.5, 28, 28.5, 29, 29.5, 30
Why half grain steps?
I suspect that the sensitivity of the test requires these half grain steps. That the test isn't sensitive enough to provide meaningful information with .1 grain or .2 or .3 grain steps. Suspect.
Do we have to do three tests, shoot three sets of cartridges?
I think so, and think that more would be better.

joe b.

[PatMarlin]

Oh ho... that is a cool test Joeb.. :Fire::drinks:

[Char-Gar]

Joe... That is a very informative test. I have heard about "ladder" testing for years, but have never tried it. I think I may have to "give it a go". thanks

Sailman ... For many years a ten shot group was the standard to determine accuracy of a rifle and a load. I still do it. If I say I have a 1.5 MOA rifle, that means for ten shots and repeatable. I find ten shots about all I can stand without fatigue setting in. I don't think twenty shots would be helpful for me.

[sundog]

Let's say you have a rifle capable of something reasonable, say 2 MOA. First shot prints, second shot has incremented charge and prints..., below the first shot?

Yup, first shot was at max distance high from center group for that load, i.e., 12 o'clock for that group. Second shot, is at max distance low for center group for that load, i.e., 6 o'clock for that group. And this occurs all the way through an incremented 10-shot string. And the next, and the next. Some right, some left, some high, some low, but all within the MOA dispersion for that increment. Whaddya got?

Now, shoot 10 rounds all same charge into one group, increment charge and 10 more into another target, and so on. When you complete all 10 sets of 10, one of the groups may be 'best'. CENTER of each group can then be plotted for the 'ladder'. But why bother? You already know which one is 'best'.

Know what else? You get to see stringing. That's a sign that something is not working right - equipment, load, nut behind the butt plate.

The dispersion of the gun's capability is counterproductive to single round incremental ladder testing.

[felix]

Amen. ... felix

[Char-Gar]

Dunno boys.... I think this ladder stuff has some usefullness. It is not the be all and end all, but it can be a tool to narrow down your search pattern... IIRC it was a custom gunsmith back in the 70's named Audett (or something close) that first advanced the idea..or at least the first in recent memory.

The search for accuracy needs more than theory, it needs some tools that people can use. There is no one tool, but if this helps some folks, then it has some use.

Corky... Yes you see stringing, but it is planned and understood stringing, which is a far cry from the run of the mill (what the heck is going on? ) stringing. If stringing can give useful information that help point the way to accuracy, then string away!

[Larry Gibson]

The Ladder test was developed by a High Power shooter as a means to quickly give him an accurate load at specific ranges (200, 300 and 600) yards with THROWN powder charges that might vary in weight. His goal was to quickly develop loads when different lots of powder were purchased and then to not waste the accuracy life of the barrel developing loads. He didn't want to have to weigh each powder charge for the large number of rounds he loaded. He found that many times shots would group together at known ranges that had slightly different powder charges. Thus he developed the Ladder Test as Joe describes it.

After working a considerable time with the Ladder Test with both jacketed and cast bullets I found it offered no real clue as to a "practical" accuracy load. I also found I was expending many more rounds than I normally did when I used the ladder test and the wanted to find that practical accurate load. Remember the Ladder Test was developed to find loads that HIT CLOSE TO EACH OTHER (within normal powder thrower variations) AT ONE SPECIFIC RANGE. It does work kind of ok for that.

It did not work for me because I shoot at various ranges with cast bullets. Ladder test developed loads were most often out of the expected velocity range that I wanted and always had an unacceptably large extreme velocity spread. If I was just punching holes in paper at 50 yards then those Ladder test developed loads were ok because they hit together regardless of velocity spread and the low velocity didn't matter. However when shooting those "accurate" Ladder Test loads at ranges longer than 50 yards the large extreme variation of velocity quickly destroyed accuracy. The lower velocity loads are also more effected by wind and may not have the necessary power for hunting or for knocking over steel targets. Since I can throw powder charges with consistancy and my loads have a low ES then I didn't need loads that may be slightly different when thrown and yet hit close together at one range. Finding several loads that hit close together at one range also did not help me find ONE accurate load that was practical when shooting at numerous distances.

As the Ladder Test was not helping me find an accurate load that was practical for me I went back to my old way. I determine what my expectected performance criteria is for the cartridge/firearm/bullet combination over the entire range at which I might shoot a target or animal. I then seek to develop the most accurate load that fits within that criteria. Let's say I have a M98 Mauser in 8mm and I have a Lyman 323470 mould. I want to shoot targets and rocks out to 300 yards so I'll want a load that will shoot as accurate at as high a velocity as the combination allows. With 323470's of correct alloy I load a series of 3 shot test loads each with 1 gr of powder difference (for this cartridge I would choose an easily ignited proven medium burning powder - probably 4895). I then shoot these test loads for group at 100 yards over a chronograph (Oehler 35P in my case). I usually will find that several of the 3 shot groups are fairly close in size. I usually will find that those several groups are most often just before the RPM threshold (when the velocity gets to high) and the groups really open. Also I'l find that the SD and ES of these groups is within expected variation meaning ignition of the powder charge is consistant along with the time pressure curve. I then go back and will load up 10 shot strings of the test loads that shot well just before the RPM threshold was found. In the case of a rifle like this that usually is just 3 or maybe 4 ten shot strings to test. After testing those I then select the load that produces the best accuracy based on group size and the uniformity of the chronographed standard deviation vs extreme spread. That testing procedure tells me what the most accurate load is with that bullet/powder combination for that rifle. That load, if acceptable, is then loaded up and I go shooting. If the load is not acceptable I will change one of the major componants, most often the powder, and test again. If the bullet is of correct weight and fit for the cartridge/powder/barrel twist and fits the throat correctly I usually have an acceptable load on the first try but have not had to test more than 3 powders to find a very acceptable load.

With heavy barreled varmint or target rifles capable of very, very good accuracy I will go a few steps farther into case prep and be more careful in bullet inspection/selection. I've found that I can find loads that will shot consistantly in the 1 - 1 1/2 MOA range without getting anal in loading. I have gotten anal in loading and find I can further improve accuracy in such rifles but I really do not enjoy such loading, as said I'd rather be shooting. While I appreciate accuracy I prefer to seek consistant practical accuracy that is reproduceable day in and day out. I've no problem with those who are seeking accuracy for the sake of accuracy but do not find one really nice group to be meaningful or interesting. I've no problem with those that do, it's their thing and that's fine.

Larry Gibson