Measuring pressure on seated bullet?

B

blsonne

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Hello all, I don't know if I'm expressing this right.

I got my 308 reloading gear last week, and I'm still in the process of setting everything up and tuning the dies. To get up to speed quickly, I've been using a Federal gold match round and working on duplicating it with my once-fired Federal brass; I'm using the same primers and the exact same bullets (175gr smk). I've got my caliper out and measured everything. When all is said and done I can pump out a round that matches the measurements of the factory roundly exactly, which makes me happy. Thanks, mystic precision! :)

However... what I cannot measure (other then guesstimate by hand) is how tightly I've clamped/seated/blah-blah-blah the bullet. After adjusting it feels nearly as tight as the factory round, but I don't like "I think" or "feels like" as units of measurement :) Is there a device or some kind of jig that can be made to measure how much force it takes to yank a bullet out of it's case?

Cheers,
B
 
What your talking about is neck tension.. As far as I know there is no tool that measures how much force is needed to seat a bullet at a given neck tension , but what you can control is how much neck tension is applied . This is done by useing a bushing type die. The bushings are changeable to size the brass 1-2-3-4 ..... thousands under the size of the bullet..

I wouldn't worry so much about how much pressure is applied to seat the bullet and focus in how much neck tension the case has and let your rifle tell you what it likes
 
OP, you are a new reloader, according to your post. It sounds like you are doing a good job of loading, so just size the cases and seat the bullets the way your instructions state to do it and don't worry about neck tension.
If they will be shot in a bolt action rifle, then don't crimp the cases.
If the time ever comes when you are consistently shooting five bullets into one ragged hole at 100 yards and you want to improve your groups, then you can think about neck tension.
 
If you want to know exactly how much neck tension your current dies are producing?. Easy to do.
Measure a resized neck with your calipers (pick/mark a location that is easily duplicated for consistency of measurement.)
Seat a bullet.
Measure the same case, same place, again. The difference is your neck tension.
Normal FL dies typically yield 4-6 thou..
Most rifles seem to shoot very well at 2 thou. tension, if accuracy is your goal.
The easy way to tweak tension is with 'customized' Lee collet, or bushing neck dies.
(they leave those necks nice and straight too)

I as well, find regular annealling to help much in keeping reloads consistent on target.
 
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