checking shoulder set back

Boyd Allen said:
For me this has nothing to do with whether or not feel has legitimate uses in precision work. It is about the assumption that the die is small enough in the back to as you say, properly size the case. It is all about what happens when the body of the case is not made small enough by a particular die, so that the case's shoulder in what keeps it from being forced farther forward in the chamber. I have adjusted many valves and other things using feeler gauges, and understand what that is all about. When someone advises adjusting a FL die by feel, they are making an assumption about the relative sizes of the chamber and the die, that may not be the case in that particular instance. Using a simple gauge, like the ones shown in post # 3 is really hard (at least for me) to screw up. What some seem to have trouble understanding is that if a die is too large for your chamber, you cannot remedy that by adjustment. A different die is required.
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I agree with you Boyd, a person would be just fine using a guage as long as they knew for sure the length of their chamber. Some of us prefer to go at things differently is all. I wouldn't want to use tight cases, even if they were the right length.
 
Pete,
I was just talking about what we tell people as basic die setting advice. I look at a lot of things on my cases. But I have learned (most of the time) not to tell someone how to build a watch, when all they have asked is the time. :D
Boyd
 
Every post on here has something in it that is fact(imo). The most important thing i can reiterate is the IMPORTANCE of a fl die that matches your chamber.

The one exception i see is.....i and everyone CAN feel .0005" or less. Remove the firing pin and plunger, and tell me how you cannot feel it. We are now assuming your fl die fits of course.

Tom
 
Another thing that comes into the mix, is that when you are working a relatively small set of cases, over the course of a weekend match, one's FL die will generally have to be screwed in a tad as brass becomes progressively more work hardened. In these circumstances putting the bolt in the rifle while sitting at your reloading table, is not an option, but the using the gauge only takes a few seconds. Of course, if you are preloading, this would not apply. Because old hard cases need a different die setting than new ones, I make a practice of removing my die from the press at the end of every session, and resetting it with a gauge at the start of a new one. Practice, and an index system has made this go very quickly.
 
gonehunting378 said:
The one exception i see is.....i and everyone CAN feel .0005" or less. Remove the firing pin and plunger, and tell me how you cannot feel it. We are now assuming your fl die fits of course. Tom
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Tom,

Whether we're talking about .0005" or .002", what we're really referring to is a gap or voided area between the case shoulder and the chamber's shoulder that hopefully we have created by pushing back the shoulder.

I submit that if you can feel something there may be or there may not be a gap or void present. You don't know for sure.

What you may be feeling is that 30% portion of the case neck that was not sized with a bushing, which helps with the centering of the case in the neck chamber, or another part of the case that's out of dimension with the chamber.

But you cannot feel a gap or void, with a bolt face or anything else, which is what we're trying to produce when we push the shoulder back, infinitesimal as it may be. I believe that we take a lot of what we do on faith, not knowing for sure if we've really accomplished what we set out to do.

When the bolt falls all the way down on it's own, you know then that you've got a gap or void, but how wide is that gap? Is it really .0005" or .002" or more?
 
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Well I'm guessing if I'm measuring each one as i set up.....it's likely not huge, if I'm going .0002ish at a time...

Example....
3.2255=snug
3.2253=felt bottom half
3.2251=felt bottom 10% DONE

Tom

Now write it down, and measure every one always forever.... redo setup if barrel is removed and re installed.
 
abintx brings up an interesting point........one I've struggled with when using bushing dies. Bushing dies, when used for full-length resizing have one glaring flaw. This flaw is that they poorly address the neck/shoulder junction. I've got 20-30 bushing dies, from nearly a dozen makers and none of them really work perfectly, even those I've had custom mfgrd with a thick 'land' at the junction instead of the fine feathered edge of say a Harrell.

I currently advocate Neil Jones dies or one-piece fixed dies because of this. The Neil Jones system is the only truly adjustable die system I've found. Using a Neil Jones die I expect to resize any size case up to and including 338 Lapua Magnum 20 times without trimming.

Bolt FALLING closed.......

There Is No Other

al
 
Quite a vast subject.......Out of the millions of dies sold by redding,forestor,RCBS,Lee etc.etc....how many people do you think try or are able to actually precisely measure to .0005"........????... VERY FEW... and I say....after working in the mfg. industry for 40 yrs.with bearing and shaft fits at +/- .0002" FEEL is extremely important.
I will still believe with a SAAMI chamber (cut properly) and std. dies you can get the job done by feel...
bill larson
 
My bushing dies have all been modified to size all the way to the neck/shoulder junction. Though for different reason(s) than offered here.

I agree with Gene about the importance of having a die that really fits the chamber and the fired cases that come out of that chamber. Probably the best example of this was a local guys HBR rig based on a shortened 308W using Lapua cases. He was having problems with cases getting thin after 6-8 firings, resulting in a couple of case head seperations. He had set the shoulder bump by feel (as advised by the 'smith) and was using the custom dies made for him by the same accuracy 'smith that had built the gun. When I checked the actual shoulder set back using my Stoney Point setup, the shoulder was being set back .011-.012 from a fired case. Checking it, I found that the case/shoulder junction dimensions were so mismatched between the chamber and the die that the shoulder had to go back that.011-.012 before the shoulder diameter on a fired case was reduced sufficiently for the case to chamber. Lapua 308W cases are pretty stout, but even they'll give up the ghost eventually gettin' hammered like that. ;)

In a couple of instances, Stan and I have had reamers ground to work with an existing die, rather than trying to make a die fit after the fact.

That said, the die/chamber/brass relationship doesn't have to be absolutely perfect for a rifle to be able to shoot accurately enough to win. Being able to operate that rifle in a way that allows the shooter to win is a different matter.......

Good shootin'. -Al
 
OK, everytime this discussion comes up I have to write this bit of info and I apologize for this and all future clarification.

When the bolt feel method is used to assess shoulder setback, extreme care has to be taken to assure you are "feeling" only the base to shoulder dimension. If the "feel" is a result of any other dimension a danger exists of excessive headspace and potential case failure. Please! - use a fired case as a "standard" and a guage to measure bump in conjunction with the bolt "feel" method. When you reach around .003 bump and your bolt still feels it needs more you need to look elsewhere.
 
It hadda' be said :)

Thank You Wilbur, and thank you Boyd Allen and others for repeatedly clarifying this point in the past. As Wilbur said, EVERY TIME THIS DISCUSSION IS HAD it must be reiterated that one must have the ability, the time, and the means . . . . . . . or THE DIE-MAKER/GUNSMITH capable of setting up the die/chamber fit to within a thousandth on all critical dimensions for the 'feel' method to work.

Just buying parts doesn't work 9999 times out of 1000

al
 
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