Making the most of a good rifle

[geargnasher]

All this being said in this thread I have one question. Is the juice worth the squeeze?

I dunno, was the Fat Lady experiment worth it? I'll bet it was to you.

Gear

[Love Life]

Yes it was.

However; what theories are being proven or disproven here? RPM threshold? Brass prep? Boolit quality? Necessary pressure? Lube?

Who has the equipment to measure all the variables? Do you have an Arbor press Gear? I have a pressure gauge that measures seating pressure and you're welcome to it as it may aid in your research concerning neck tension.

[geargnasher]

To really attack the broad subject Brad started with here, we might best be served by breaking it down into some transferable, minute details under several sub-sections. For example, the subject of neck tension, flare, and chamber neck clearance is but one tiny part of cartridge case preparation for accuracy. In general, close tolerances are the key, when and where we can get them, but what if Bubba with his wallered-out '06 chamber can't get components to do that? There are tricks to help, but maybe he'll never get to shoot accurately at high velocity with that system. So there are general guidelines, and there are different specific approaches to tackle the individual rifle personality and work within what's given. Remember, I'm still just referring to neck tension, flare, and chamber neck clearance here.

Ignition consistency and how that relates to barrel harmonics is another lengthy, variable subject. Generally, with a bolt-action, having consistent pressure between the datum point on the shoulder and the bolt face makes a very noticeable difference in point of impact. I say that in a general sense because I've found it to be true in three rifles, one of which uses a rimmed case. When I started headspacing on the shoulder and sorting rounds fired based on lever effort to latch the locking bolt, my group shape improved dramatically. Does that subject fit under case prep? You bet it does, because you're controlling action preload, and thus the transfer of energy between cartridge case and action/barrel, at the reloading press.

I think it's possible to break this down into basic categories, share experiences that affect the same subjects differently in different situations, and get a sort of general set of "what works and what don't" guide that others may be able to absorb, but in the end each handloader is going to have to hash it out for themselves. Having a set of guidelines and discussion of what affects each part of the fitting, loading, and shooting process in various guns/calibers may help shorten the learning curve a bit, but I think it would be a full volume or two. Take the four points I made way back on page one and expand them each into several hundred pages, then you might have it covered. Then someone who knows a lot more about this than me will add a few other topics and it gets huge again discussing them in detail.

Take the statement "get the boolit into the bore absolutely straight", which is what Bob has told us over and over again, then take two years of your life figuring out how to accomplish that in just one gun. That's what I did, and I know I only learned part of what to do.

Gear

[Love Life]

Sounds solid to me.

I know sharing info can be frustrating (especially on a gun forum) because everybody wants to chime in (I'm doing it now!!) with "stuff". Then it evolves into a monster. However; nothing is stopping the OP or group of contributors from bulling through the noise and then summarizing at the end and allowing onlookers to make their own decisions on what they want to do. In guided discussions, you guide it. Ignore the fluff (like this post...) and keep it on track.

I've seen it mentioned several times in the last week how terrible it is that some members won't contribute because they want to be in control. Well...then they have made themselves useless and irrelevant for the most part.

I want to thank all of you for going down this road and for the hours of research and trial and error you are about to do.

Thank you.

[btroj]

So much of it is learning what to look for and how to look for it.

When I started shooting Highpower I figured case lube was case lube. Read a few books, do some testing, do some measuring. What did I learn? That how we apply lube makes a difference in that bolt face to datum line measurement Gear mentioned. Yep, over lubing the neck and shoulder can lead to a .001 change in that measurement quite easily.

Ok guys, Gear made a good suggestion. Break this into little bits and take it in manageable bites.

What bite first? I will let someone else start that thread.

[Love Life]

First bite? I'd say brass prep (getting your brass perfect-ish for your gun) or boolit quality needs to be first. Those will be the largest variables to confront you 1st. I have tools to lend (concentricity gauges and stuff) to help, but sadly I am unable to contribute where the tires hit the road.

So, that being said I will bow out of this and watch from afar. Pm me if any of you want to borrow some stuff.

[geargnasher]

I'm not really interested in proving or disproving anything, only finding what works. All moving objects have resonant frequencies and multiple harmonics of those frequencies (study music theory or listen to Eddie Van Halen play guitar and you'll learn a bunch), and boolits and rifles are no different. Orbital mechanics is enough to show us that there will be several ideal, 'smooth' rotational velocities for a given object. A given rifle system has ideal and non-ideal performance points, it is a fact, not a theory. I'm interested in working with these facts and postulating solutions to "limits" as they are encountered, testing those theories, and finding factual solutions to things we think are issues, like pushing past an accurate velocity limit in a particular rifle. Some things we know, some things we don't but have our pet theories. What I like to do is use theoretical discussion and educated guesses to devise tests that will give us facts, and bury the theories that when tested, don't lead us in the direction we want to go.

As for equipment, people on this site have devised and improvised all manner of neat stuff to test things. We need to quantify variables so we can study them effectively and compare the effects of measured changes to those variables. THAT is what I want to do.

I made a Timken-style wear tester to compare film strength of various lubes from zero to several hundred degrees. It has been handy, but only tests one thing that may or may not be relative to the system. A micrometer, reloading scale, and a lot of "feel" is required, too. The best tool for testing so far has been my mind, and the target has been the best way to solidly judge results.

Gear

[geargnasher]

OK, Brad, let's deviate for a minute and poll how to break it down, because I don't know it all by a long shot.

We could do it like this: Come up with the main topics (evaluating the suitability of a rifle for the task [crown, bore condition, straight chamber, pound casts, reading light rings, checking headspace, bedding, etc etc], guidelines for how to fit ammo and boolit, case prep techniques for various chambers, how to make a good boolit [casting, sizing, checking, quality-control, etc], mechanical loading techniques aimed at fit, harmonics, and not damaging the boolit during launch, loading techniques to solve problems, on and on.), and THEN let the OP keep updating and modifying THE FIRST POST to distill the facts for readers. The discussion, demonstrations, etc. could go on for hundreds of posts, but the key points and facts keep getting pulled to the front just like Tim's "Accurate Molds" thread where contributions are compiled into the first post in an orderly manner.

Whatcha think? The topic of this thread is broad, "Making the most of a good rifle", so what does that mean? How do we want to break this down into, say, less than ten separate subject threads?

If we got it narrowed down to just a few main topics, and perhaps left the gunsmithing/rifle building part to a separate thread and focused on JUST how to "run what ya brung", we could get the staff to agree to sticky a few discussion topics ahead of time.....but we need a good plan first.


Gear

[btroj]

Yep, the mind is what matters. That and a desire to learn, and ability to make good observations, and to make appropriate conclusions from those observations.

The how isn't always as important as the what.

Oh, music theory? No thanks, I get enough art history at home. Now Eddie I can do, saw him n concert and he is the real deal.

How much of the harmonics battle is eliminating them and how much is learning to control them or make them predictable? Do we need to worry about resonance of a variety of frequencies? How do we know that time issue and not someone else?

[Love Life]

How would you know if the bullet is damaged (or not) during the jump (unless you jam) into the rifling? How do you know if the rifling is damaging the boolit? I don't feel recovered boolits fired from the gun would show this.

However; what I have in mind is this. I have seen a grease gun with zerk fitting to remove a stuck bullet from the bore. What if something like this could be fabricated, attached to the CHAMBER end, and a grease gun used to push the bullet down the full length of the barrel and out of the muzzle? Wouldn't that give you a good bit of info?

[geargnasher]

Remember the "Basement Articles" Brad? That was my concept, based on only what I know and how my mind breaks that knowledge down, of how to make "small bites". Those were technical, rather than academic articles, and to be effective they really need to be a little bit of BOTH.

Like LL suggested, case prep is a biggie. I wrote "Case prep for accuracy", but it was so inter-related to rifle vibrations, chamber/bore dimensions, and advanced loading techniques that it couldn't be the first topic.

I suggest starting with a how-to discussion of the goals. Accuracy alone? Accuracy at well above (or below!) what's considered average for cast boolits? Accuracy to a hundred yards and to heck with the rest? Accuracy at long distance? Then continue into how to size up your rifle, with reference to threads about how to select parts to scratch-build a gun. I'd let Tim handle that thread, and he can learn a lot from sorting out what's been posted already in the past week or so on that.

I'm going to assume that, if we consider high-velocity cast boolit accuracy as the PRINCIPLE objective, we can drop a lot of the fluff and start right into pound casting, reading light rings, checking the muzzle condition, headspace, and flow right into the big subject of loaded cartridge and boolit fit. I see I have a pm, so I'm going to stop derailing this thread for a minute and see if we can work this out without cluttering up things here...

Gear

[Love Life]

I got to thinking today while I was wrist deep in a bucket of KFC. Why are we discussing obturation. I thought the whole purpose of boolit fit got rid of that. It has me wondering...if the boolit is already sized to whatever you prefer over bore diameter, does it need to obturate? Is it even obturating?

Wow, all the red squiggly lines are telling me I am creating new words.

[btroj]

Because as it travels down the bore it is constantly pulling away from the lands on the trailing edge. Pressure on the bullet and lube prevent gas cutting there. Lose that "seal" and you have leading.
Think of your handgun bullets and the cut coating. What slews the back edge of those cuts? Not the coating.

[Love Life]

I really wish I could nail down a rifle length polygonal rifled barrel. Looks like a call into PacNor is in order. We are concerned about the boolit being perfect from leaving the case to exiting the bore, so is that uber sharp rifling beneficial to a cast boolit?

[runfiverun]

why do even land and groove rifles with fairly deep rifling shoot cast better?

you guy's are on the track of questioning and figuring out why the relax point down the barrel matters and what it relates to too.



here's how I have been getting success.
step one.
focus on the cases [even neck tension/correct case thickness] and the centerline of the barrel relationship first.
get that right.... it don't matter what kind of projectile you are using it matters.
step two.
focus on mechanical fit of the boolit/bullet [think about dicks success with the heavy bullets compared to the lighter ones and why]
step three.
focus on powder speed. [again back to the fat lady why retumbo over 4831]

get all that working together,[and you have success at a reasonable velocity of 23-2400 fps]
this is when start mucking about looking for the other couple of hundred fps.
alloy and lube tweaking are your next two steps, they allow you to add more powder to the case.
at some point you run out of room and have to step up the powder speed, quite often this is accompanied by an oal change.
this is also a point that gets you about 150 feet per second down the road from the initial accuracy node[s].
dial all that in and change primers looking for the final accuracy tweak.
if you make it to 2600 fps, you start changing the b.c of your boolit and down range trajectory [300 yd mark] into something magical.
your also done and bored with the rifle and are looking for a new project...
but every time you look at it you feel a sense of pride and accomplishment.

[Love Life]

R5R and CBRick- Thank you for the information. It gives me a lot to chew on. I don't know why, my mind keeps wandering back to polygonal rifling.

Using coatings, and recovering boolits, it is easy to see the actual cutting that sharp rifling does to the boolit. Also, the recovered boolits fired in polygonal rifled barrels show there is no cutting. Also the leade into the glock barrels is very gentle. I have seen a tangible accuracy difference in my pistolas and borrowed pistolas between the two types of rifling.

Now, according to what I have found, Polygonal rifling creates a better seal and doesn't have te sharp edges: http://www.ballisticsbytheinch.com/rifling.html. I looked other places and much remained the same.

Brad brought up Obermeyer barrels. That also got me to thinking because his (Obermeyer) barrels have a smaller bore diameter for caliber. That is pretty interesting.

Once again though it all comes back to: What are those sharp edges in the rifling doing to the boolit?

My brain hurts and I am off topic which is making the most of a good rifle.


Loading practices will win the day on that one, but I also am getting hung up on boolit design. I see many boolits with a sharp, square shouldered front driving band. Is that beneficial? Would a slow taper down to the bearing surface be better?

[Love Life]

Looks like Lothar Walther makes polygonal rifled 308 barrel blanks. When I burn out the fat lady again that is what I'll get. I will figure this out!!

[cbrick]

Speaking of neck tension and neck expanding dies, here's something I started pondering a couple of years ago: Elasticity.

Cartridge brass is flexible, but it is also malleable. Squeeze it a little, it bounces right back. Squeeze it more, it stretches and bounces back much less. Anneal it, it loses a lot of its flexibility. Gear

That's not entirely accurate and why I call annealing an art form. A very unscientific test of cartridge annealing is to use needle nose vice grips adjusted to just contact the neck, now adjust them in just a bit, .020" - .030" and squeeze the neck and PROPERLY ANNEALED necks will return to it's original shape. Too much annealing and they won't, it may still be malleable but it won't be flexible and it's not because they were annealed it's because they were annealed too much. If they loose this flexibility they give inconsistent grip on the boolit.

Rick

[Love Life]

If the shot matters it does yes.

As long as plinking ammo goes bang not a lot of anything matters short of leading up a barrel. If the intent of a loaded round is to place it in a specific spot on a target over on yonder hillside there is much in the details.

Rick

Troof.

[nekshot]

I think I need a shot of whiskey, but I'm listening!!!