What is the best tool for checking the amount of shoulder set back when adjusting dies?
What I have been doing requires no tool other than what is needed to disassemble the bolt. I chamber a piece of brass that has been fire formed in that chamber,(do not re size), close the stripped bolt (without the firing pin and spring). The bolt should close most of the way with no resistance, then require a small amount of finger pressure to close completely. Using this "Feel method" adjust your sizing die so that it bumps the shoulder just enough that the bolt will close with just the slightest bit of finger pressure required to completely close. If the bolt drops shut on its own, you have bumped too much, back the die out a bit, if the bolt requires more than the slightest amount of finger pressure to close, you haven't bumped enough, turn the die down a bit.
Hope that this is helpful,
Dick
Dick and Bill,
As long as the sizes of the chamber and die are in the proper relationship, what you do can work, BUT if the die is too large for that particular chamber, by the time that you get the bolt feel that you described, the shoulder will have been set back too far. I have had friends that ran into this exact problem, so it is not some purely theoretical thing. Measuring is fast and easy. That way, you know how much you are setting back the shoulder. As you are undoubtedly know, repeatedly setting shoulders back too far, can lead to incipient and then actual case head separations.
Boyd
Using this "Feel method" adjust your sizing die so that it bumps the shoulder just enough that the bolt will close with just the slightest bit of finger pressure required to completely close. Dick
Dick,
With all due respect and I'm not try to be sarcastic, but being able to feel a .001" to 002" of mechanical movement on the shoulder of a case, with finger pressure on a bolt, has to be a gift. What does .002" to .003" feel like? .003" to .004"? What happens if you injure the e tip of your bolt pushing finger?
at didn'e t hav
For all others, IMHO, I believe, for consistency in results, measurement with a highly sensitive gauge, no matter which one, is probably the best avenue to take, especially if one is looking for the precise .0005" to .002" of movement so often sought.
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.
it is quite possible to feel a couple of tenths with ones hands and fingers.
Pete,
A couple of tenths maybe, but we're not talking about tenths [.2"], or even hundredths [.02"], we're talking about thousandths [.002"] and 5 ten thousandths [.0005"]. I don't believe any human, gunsmith or not, can actually feel thousands or ten thousandths.