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joeb33050
01-15-2009, 01:04 PM
THE SEARCH FOR ACCURACY WITH CAST BULLETS

This recipe describes a method of achieving reasonable accuracy, that I define as reliably repeatable sets of five-5 shot groups averaging under 2” at 100 yards.
It is not the ONLY recipe, it may not be the BEST recipe, but it is a recipe that will work.

The Steps
The shooter: familiar with reloading, willing to learn how to cast bullets, and own or be prepared to buy the necessary equipment and to carefully cast, load, shoot and record the results. (Much used reloading and casting equipment is available at various shooting forums or auction sites.) The three editions of the Lyman Cast Bullet Handbooks and any edition of their Reloading Handbook are of great help.
The gun: a commercial non-military bolt-action 30-caliber rifle, such as a recent Savage, a Remington, or a Ruger. All copper fouling from jacketed bullets should be cleaned from the barrel.
The sight/s: a telescopic sight of at least 6 power, preferably with an adjustment to eliminate parallax, or, as a more expensive and less desirable alternative, a set of good aperture iron sights.
The caliber: 30/06 Springfield or 308 Winchester
The bullets: Lyman 311299 or 314299, of good quality, gas checked, sized correctly, lubed with a good commercial lubricant.
The powder: IMR 4227. The charge must be appropriate for the cartridge and bullet. Lower velocity loads from the Lyman 48th Reloading Handbook should be used.
The bench rest equipment and technique must be adequate to allow precision shooting.
Meticulous records must be kept of all casting, loading and shooting information.

Some Notes:

The Bullets
Cast the bullets from wheel weights with maybe a little tin added.
Visually inspect the bullets, re-cycle the rejects. Weigh sort the bullets if you wish.
(The following steps require a Lyman 45 or 450 or 4500 lubrisizer, RCBS or Saeco lubrisizer or Lee Lube and Size kit.)
Seat the gas checks in a separate operation.
Size the bullets to the correct diameter.
Lubricate the bullets with a good commercial lube, such as NRA Alox lube. No homemade lubes!

Fitting the bullets to the gun
The 311299 and 314299 bullets are about 200 grains with bore riding noses. The 314299 bullets are a bit larger than 311299s, the noses are larger in diameter, and, until sized, the base bands are larger.
Both bullet molds today are 2 cavity. Mark the cavities so that you can tell which cavity the bullets came from. There is always a difference in bullet weight and some dimensions from one cavity to the other.
Cast bullets are not round, and dimensions of the as cast nose and base bands show this. I cannot ever recall a bullet with dimensions +/- a tenth, (.0001”), and normally 3 or 4 or more tenths difference is the rule.

Bullet fit
1. The cartridge should chamber with a bit of resistance.
2. The bullet should not stick in the chamber when the chambered cartridge is extracted. No de-bulleting!
3. The base of the bullet should be in the neck, not down inside the case. If just the gas check is below the neck, there’s generally no problem.
4. The nose of the bullet should be engraved by each land of the rifling.
5. The forward-most end of the front base band should slightly mash into the origin of the rifling.

Increasing the amount of tin and/or antimony in the alloy yield slightly larger bullets.
Sizing the bullet in a lubrisizer makes the nose bump up larger.
Bigger as-cast to sized differences make the nose larger than smaller differences. Size a .314” to .308” and the nose will bump up more than when sizing from .314” to .312”.
Softer bullet noses bump up more than harder bullet noses.
Bullets with base bands sized to different dimensions may/will have different overall lengths.
Rifle barrel lands at the chamber end wear or erode, so that cartridge overall length increases slightly and slowly as the rifle is shot.
If the cartridge that goes in the gun has a lot of base band below the neck, change something.
If the cartridge goes in the gun, has just the gas check in the case mouth and doesn’t engrave the bullet nose, change something.
If both 314299 cavities make bullets too big, go to the 311299. If the 311299 bullets are too small, either the gun or the mold is incorrect.
If both 311299 cavities make bullets that are too small, go to the 314299. If the 314299 bullets are too big, either the gun or the mold is incorrect.

Reloading
Get at least 120 good cartridge cases from the same lot, at least with the same headstamp.
Full-length size them. (New cases will shorten when fired. Used cases won’t, much.)
Measure the lengths and trim to the same length. (Same length cases are required for proper case mouth “belling” with the “M” die.)
Chamfer the case mouths in and out. (Lee makes inexpensive tools to chamfer case mouths and trim cases to length.)
Bell the case mouths with a Lyman “M” die in a press.
Prime (Lee makes a great and inexpensive priming tool.)Any large rifle primer will work fine.
Cartridge “lot” size is 35, make a set of 35 cartridges for each trial load. (The set of 120 cases allows loading three lots of 35, with thirteen spares.) Just checking.
Charge the cases with powder.

Lyman 48th Edition Reloading Handbook
308 Win., 311299 at 200 grains
IMR 4227
19.5 grains starting load to 26 grains maximum load
Start with 18 grains, and then go up in 1-grain steps to 22 grains

30/06 Springfield, 311299 at 200 grains
IMR 4227
21 grains starting load to 29 grains maximum load
Start with 19 grains, and then go up in 1-grain steps to 24 grains

ALWAYS CHECK A PUBLISHED LOAD TO SEE IF IT MAKES SENSE!!!!

Inspect the cases with a flashlight to detect “no powder” and “double charges”.
Seat the bullet to the correct overall length.

Shooting
Shoot only on a day with reasonable weather. No hurricanes or blizzards.
Use a reasonable front and rear rest. Rests can be made of shot bags or blue jean legs, or bought for prices ranging from OK to crazy. I have used a Hoppe’s front rest as well as home made rests, and they all work well.
Push a patch through the barrel.
Get comfortable at the bench.
Shoot 3 foulers, and then two 5-shot groups for record in about 15 minutes. Don’t let the barrel get too hot!
Clean the barrel.
Shoot 3 foulers, and then two 5-shot groups for record in about 15 minutes. Don’t let the barrel get too hot!
Clean the barrel.
Shoot 3 foulers, and then ONE 5-shot group for record in about 10 minutes. Don’t let the barrel get too hot!
Clean the barrel.
You’ve shot five 5-shot groups and 9 foulers for 34 shots. What about the #35 cartridge? If you call a honked shot, you’ll need that #35 cartridge to make the fifth shot in the group.

Recording the data
Write everything down. Write the reloading data down when you reload, and the shooting data on the day you shoot. DON’T WAIT FOR TOMORROW, YOU’LL FORGET SOMETHING.
Write down the powder charge and primer make and lot numbers if you wish and the overall length and bullet # and just everything. If you pull a shot, honk it out of the group, and if you call it honked before you look through the scope, then take another shot for record. Don’t lie to yourself.

joeb33050
01-15-2009, 01:05 PM
NEXT ACCURACY ACTIONS

If the gun will not shoot reliably repeatable sets of five-5 shot groups averaging under 2” at 100 yards after following the recipe above, then what?
See the following ACCURACY STEPS.
The targets may give us hints about what to do next.
If the groups show more vertical than horizontal dispersion, this may indicate a variation in velocity. More powder or a hotter primer sometimes reduces this dispersion.
If some of the bullets are going through the target cocked or tipping then this suggests that more powder and a higher velocity may reduce the tipping and increase accuracy. Note however that excellent accuracy is sometimes found with tipping bullets.
If the groups do not tend to be round, there may be a problem with action bedding or barrel inletting or floating. Groups should tend to be round, some may show fliers, but most should look round.

If the gun does shoot reliably repeatable sets of five-5 shot groups averaging under 2” at 100 yards, and if better accuracy is desired, then some of the following ACCURACY STEPS should be taken.

The question then is, for either case-accurate to under 2” or not, which steps should be taken and in what order?

joeb33050
01-15-2009, 01:06 PM
ACCURACY STEPS


These two steps need be done only once, are easy and inexpensive, and may increase accuracy.
Uniform primer pockets
De-burr flash hole

This step is easy and may increase accuracy.
Clean flash holes

This step is time consuming, but serves to identify the oddball low or high weight bullet that may be a flier.
Weigh segregate bullets


These steps are in no particular order.
Change lube
Change primer
Change sized bullet diameter
Change powder
Change powder charge in .1 grain steps
Change powder charge in .5 grain steps
Change powder charge in 1 grain steps
Change powder charge in ? grain steps
Change bullet hardness
Make cartridge case length = chamber length -.005”
Weigh segregate cases
Weigh segregate primers
Weigh segregate gas checks
Anneal gas checks
Anneal case necks
Turn case necks
Inside ream case necks
Ream flash holes to a uniform diameter
Orient the case in the chamber
Orient the bullet in the chamber
Orient the bullet in the case and the case in the chamber


These steps require some substantial money and/or expertise
Size case necks in a Redding or Wilson replaceable bushing style neck sizer
Seat bullets with a precision micrometer adjustable sizing die
Glass bed the rifle action
Ream the chamber throat
Get a taper die to match the reamed chamber throat and taper the bullets
Re-crown the barrel
Lap the barrel

pdawg_shooter
01-15-2009, 01:45 PM
Or you could do it the easy way........paper patch!

runfiverun
01-17-2009, 12:59 AM
if i was a new guy looking to get into shooting cast in a rifle.
i think those would be pretty helpful tips.
but i really wouldn't be too keen on the idea of cleaning my bbl every 10-12 shots.
part of my rifle criteria is to not have to clean the bbl.
push a wet then dry patch once or twice a year yes but not every few shots,
you might want to add that cleaning may not be necessary with a proper lube for the load.

joeb33050
01-17-2009, 08:28 AM
There are two possibilities, either following the recipe resulted in groups averaging under 2", or the groups are larger than 2".

Over 2"????What steps should be taken, in what order, to get to <2"???
(If groups average 4", probably annealing gas checks won't help.)

Under 2"????What steps should be taken, in what order, to get smaller groups?

I've listed some of the possible steps.

What steps when, how to search for accuracy, that's the question.

???????????????????????????????
joe b.

joeb33050
01-17-2009, 08:38 AM
if i was a new guy looking to get into shooting cast in a rifle.
i think those would be pretty helpful tips.
but i really wouldn't be too keen on the idea of cleaning my bbl every 10-12 shots.
part of my rifle criteria is to not have to clean the bbl.
push a wet then dry patch once or twice a year yes but not every few shots,
you might want to add that cleaning may not be necessary with a proper lube for the load.

I've spent a lot of time, asked a lot of questions, about cleaning barrels. The answers sum up between "once every 10-15 shots" and "annually, or never".
Skilled 22 RF shooters say the same thing, wide variation. in cleaning frequency.
I once had a 32/40 barrel ?corrode? after shooting Darr lube, IMR4227, Rem 2 1/2, and not cleaning for a few days-in MA in fall. Since, I've always cleaned and recommended cleaning CF guns every time a gun is shot.
After a lot of shooting for group, with many lubes, I'm convinced that group averages are smaller when cleaning as described, every 13 shots or so. Wouldn't want to have to prove it, but it seems so.

BTW, you mentioned slugging the chamber/barrel. What do you do with the information?
joe b.

runfiverun
01-18-2009, 09:59 PM
by slugging the bbl in parts you know what you are dealing with.
the smallest part of the bbl is what your boolit is going to be swaged to.
however by knowing what your throat looks like it will help you pick a boolit design that will help you decide what boolit to start with and how far out you can seat it.
this falls into line with your keeping the boolit into the neck of your case.
for instance if you have a very short throat [like a k-31, or most rugers in 30 cal]
then a fit in your 308 may be limited to some designs that don't carry enough lube to get good [1"] accuracy over about 1900 fps. think rcbs silh.
however that same boolit may be a very poor choice for a 30-30 at 2200+ fps.
where a loverign design will shine as fast as you can push it, or even in a 0-3 sized a bit larger and seated out further you may be able to get to 2100.
i know you touched on this some but just trying a bigger diameter is not always [or even most of the time] the answer to accuracy.

Maven
01-19-2009, 01:16 PM
"I've spent a lot of time, asked a lot of questions, about cleaning barrels. The answers sum up between "once every 10-15 shots" and "annually, or never". Skilled 22 RF shooters say the same thing, wide variation. in cleaning frequency."

With some powders, e.g., WC 860 and IMR 5010, you HAVE to dry swab the bbl. after every 5 - 10 shots (10 -15 shots would be a blessing!) else you'll get unburned powder particles in the chamber and powder dented cases. Surprisingly enough, accuracy doesn't seem to suffer.

As for .22RF, I happened to visit a .22BR shooter & gunsmith* the other day (to pick up some match ammo.) and discussed this very thing. What Joe B found is exactly the case since the proprietary lubes are not equally effective in all, even match, bbl's. E.g., the old Federal 900B match .22RF ammo (1,040fps), used to leave Pb deposits ahead of the chamber, resulting in cleaning with an Ed's Red-soaked patch + dry patches after each match (20 shots for record + as many foulers as needed, given the 30 min. time limit.).

*builds .22BR rifles (Monell Custom Guns, 845-744-3021)

joeb33050
01-20-2009, 12:34 PM
If the gun will NOT group in 2” at 100 yards:
I buy guns, get them to shoot, and send them down the road. (I keep just one of each.) This is my hobby.
The folowing may sound like an untruth, but it isn’t.
I can not remember a gun as described that would not shoot; then I did something; then it shot well. I can remember only 2 guns that did not shoot well, that I gave up on. One was a 1903 Springfield with a Lyman 48? or 57? and 17 front sight. The other was a TC Contender with barrels, over the years, in 32-20, 30-30, 30-30 Carbine, 7MM TCU and 6.5MM TCU-maybe others. I never got either to shoot well, both went down the road.

So, I write with limited experience, counting on others for help. Frank 46 on “Cast Boolits”, John Bischoff, William W."Bill" McGraw, Paul Brasky and Dave Goodrich have made some good suggestions, in quotes below.

If the gun will NOT group in 2” at 100 yards:

#1A “Have another, experienced, shooter try your rifle. Sometimes your grip
/ forearm rest / buttstock rest can cause problems. I had that shown to me
once, much to my chagrin, moving the forearm back two inches on the rest
cut my groups by 30%”.

#1B For a gun with a “free-floating barrel, check the gun for interference between the barrel and stock. Use something thicker than a dollar bill, maybe 3 dollar bills.
Take the barreled action out of the stock, inspect both for any signs of interference or rubbing or polishing. If there is a sign of interference, sand the stock. This has to do with interference between the action and the stock
Put cardboard shims, matchbook cover ~ .025”, under the front and rear receiver rings, then put the gun together. This will free-float the barrel.
If some of the above works, “bed” the action in the stock.

#1C Check the scope screws and action screws to make sure that there is nothing loose. I have never used a torque wrench on action screws, yet.
“Check tightness of scope base screws, and scope ring screws.”
”Set action screws with a torque wrench to the approximate tightness
you use. The main screw might like 50 inch-pounds and the rear one
somewhere around 35 inch-pounds. The third one, if there be one,
might be happiest around 20 inch-pounds. Your rifle WILL be different
from all other rifles.”

#2 “Try a different scope.” I have seen and talked to other shooters who have found that the scope sight is defective, and causes inaccuracy. I have never had an inside-adjustable scope that caused inaccuracy, and cured an outside-adjustable Lyman STS scope of this trait by cleaning the adjustment ring.

Now I’m sort of at a loss. If none of the above will get the rifle to shooting into 2”, what to do next?

joe b.

The Nyack Kid
01-20-2009, 12:51 PM
If the gun will NOT group in 2” at 100 yards:
I buy guns, get them to shoot, and send them down the road. (I keep just one of each.) This is my hobby.
The folowing may sound like an untruth, but it isn’t.
I can not remember a gun as described that would not shoot; then I did something; then it shot well. I can remember only 2 guns that did not shoot well, that I gave up on. One was a 1903 Springfield with a Lyman 48? or 57? and 17 front sight. The other was a TC Contender with barrels, over the years, in 32-20, 30-30, 30-30 Carbine, 7MM TCU and 6.5MM TCU-maybe others. I never got either to shoot well, both went down the road.

So, I write with limited experience, counting on others for help. Frank 46 on “Cast Boolits”, John Bischoff, William W."Bill" McGraw, Paul Brasky and Dave Goodrich have made some good suggestions, in quotes below.

If the gun will NOT group in 2” at 100 yards:

#1A “Have another, experienced, shooter try your rifle. Sometimes your grip
/ forearm rest / buttstock rest can cause problems. I had that shown to me
once, much to my chagrin, moving the forearm back two inches on the rest
cut my groups by 30%”.

#1B For a gun with a “free-floating barrel, check the gun for interference between the barrel and stock. Use something thicker than a dollar bill, maybe 3 dollar bills.
Take the barreled action out of the stock, inspect both for any signs of interference or rubbing or polishing. If there is a sign of interference, sand the stock. This has to do with interference between the action and the stock
Put cardboard shims, matchbook cover ~ .025”, under the front and rear receiver rings, then put the gun together. This will free-float the barrel.
If some of the above works, “bed” the action in the stock.

#1C Check the scope screws and action screws to make sure that there is nothing loose. I have never used a torque wrench on action screws, yet.
“Check tightness of scope base screws, and scope ring screws.”
”Set action screws with a torque wrench to the approximate tightness
you use. The main screw might like 50 inch-pounds and the rear one
somewhere around 35 inch-pounds. The third one, if there be one,
might be happiest around 20 inch-pounds. Your rifle WILL be different
from all other rifles.”

#2 “Try a different scope.” I have seen and talked to other shooters who have found that the scope sight is defective, and causes inaccuracy. I have never had an inside-adjustable scope that caused inaccuracy, and cured an outside-adjustable Lyman STS scope of this trait by cleaning the adjustment ring.

Now I’m sort of at a loss. If none of the above will get the rifle to shooting into 2”, what to do next?

joe b.

Ahhhh , check for Crown Damage ? Barrel Bulge ?

I've been following this thread with interest , keep it up Joe .

runfiverun
01-20-2009, 01:07 PM
crown damage is a big area in accuracy,or lack thereof.
it is also one area that is easy for someone to do at home.
you also need to look at the trigger, i had a model 70 that i knew was a good rifle yet it would not group very well, i was alternating between it and another model70 when it dawned on me that even though i had the group clustered around the center of the target and the crosshairs.
i was slightly pushing and pulling on the rifle trying to hold it in position for the break.
just by taking out the creep and slightly lowering the break i was able to shrink groups nearly an inch,
.

mainiac
01-21-2009, 09:14 PM
I my opinion, you forgot the most important step,,,, if your not shooting over windflags, then you cant hope to shoot small groups. Even a nice calm day will have winds pushing at your bullet. The reverses will kill your groups! Of course there also the opinion that wind will blow a bullet into the group,as well as out of a group!

joeb33050
01-22-2009, 08:40 AM
Updated, with comments from forums


If the gun will NOT group in 2” at 100 yards:
I buy guns, get them to shoot, and send them down the road. (I keep just one of each.) This is my hobby.
The following may sound like an untruth, but it isn’t.
I cannot remember a gun as described that would not shoot; then I did something; then it shot well. I can remember only 2 guns that did not shoot well, that I gave up on. One was a 1903 Springfield with a Lyman 48? Or 57? and 17 front sight. The other was a TC Contender with barrels, over the years, in 32-20, 30-30, 30-30 Carbine, 7MM TCU and 6.5MM TCU-maybe others. I never got either to shoot well, both went down the road.

So, I write with limited experience, counting on others for help. Frank 46, ”The Nyack Kid” on “Cast Boolits”, “linoww” on the CBA forum
John Bischoff, William W."Bill" McGraw, Paul Brasky and Dave Goodrich have made some good suggestions, in quotes below.

If the gun will NOT group in 2” at 100 yards:

“Shoot the rifle with a good jacketed bullet load. If the gun and load are capable of at least 1.5" groups at 100 yards, the gun should shoot cast bullets accurately.”

“Check for crown damage or a barrel bulge”
Look at the barrel crown under a good light and a magnifying lens, check for any damage. If there is damage, re-crowning the barrel is fairly simple and may cure the problem.

Push a cleaning rod with a tight patch through the barrel, feeling for any sudden lack of resistance that indicates a bulge in the barrel. If there is a barrel bulge, the rifle may not shoot cast bullets accurately. However, I have seen, been told about and read accounts of bulged barrels shooting accurately.

“Have another, experienced, shooter try your rifle. Sometimes your grip/ forearm rest / butt stock rest can cause problems. I had that shown to me once, much to my chagrin, moving the forearm back two inches on the rest cut my groups by 30%”.

For a gun with a “free-floating barrel, check the gun for interference between the barrel and stock. Use something thicker than a dollar bill, maybe 3 dollar bills.
Take the barreled action out of the stock, inspect both for any signs of interference or rubbing or polishing. If there is a sign of interference, sand the stock. This has to do with interference between the action and the stock
Put cardboard shims, matchbook cover ~ .025”, under the front and rear receiver rings, then put the gun together. This will free-float the barrel.
If some of the above works, “bed” the action in the stock.

Check the scope screws and action screws to make sure that there is nothing loose. I have never used a torque wrench on action screws, yet.
“Check tightness of scope base screws, and scope ring screws.”
”Set action screws with a torque wrench to the approximate tightness you use. The main screw might like 50 inch-pounds and the rear one somewhere around 35 inch-pounds. The third one, if there be one, might be happiest around 20 inch-pounds. Your rifle WILL be different
from all other rifles.”

“Try a different scope.” I have seen and talked to other shooters who have found that the scope sight is defective, and causes inaccuracy. I have never had an inside-adjustable scope that caused inaccuracy, and cured an outside-adjustable Lyman STS scope of this trait by cleaning the adjustment ring.

Now I’m sort of at a loss. If none of the above will get the rifle to shooting into 2”, what to do next?

MT Gianni
01-22-2009, 10:32 AM
Joe, I assume that the gun will shoot OK with jacketed but not cast. I would make sure that jacketed/factory works at this point. That would ensure a chamber and throat are centered. Cerrocast may show something, you may be into the weak or inconsistent firing spring resulting in inconsistent firing pin fall.