different headspace ?

[earl39]

Ok guys i have head-spaced with gauges and with a case sized in my dies and then go back with 2 pieces of scotch tape for a no go gauge and i have used actual no-go gauges. I have been thinking about this and if .002 setback is what we are looking for when we resize would it not stand to reason when we set head-space with a case sized in our die that a single piece of scotch tape on the base would set head-space at approx .002 over case length which should let us leave our die setup alone and have .002 shoulder setback every time we reload.
If my math is wrong correct me but it all seems to come to the same conclusion. What are your thoughts guys.

[stangfish]

That theory holds water if your tape is .002 think and you only shoot ammo that you reload and check headspace to be exactly the same every time. You will find that any variation in case lube can/could alter the headspace dimension.

[earl39]

They theory holds water if your tape is .002 think and you only shoot ammo that you reload and check headspace to be exactly the same every time.

checking the tape thickness would be the easy part. Using a case sized in your own die would suggest plans to only reload but i can see the problem if factory ammo was used but there could be a problem with factory ammo even if the tape was not used. Head-space would not change unless your barrel was loose or you made a change in your dies.



You will find that any variation in case lube can/could alter the headspace dimension.


If you figure in case lube as changing head-space then no matter how you head-space a barrel you could never get it perfect.

[gotcha]

Hi Earl, I'd agree w/ your idea of F/L sized case + .002" of tape. HD SP gauges can vary a bit. "0" to .003" in my experience & your method would rely on the "constant" of your sizing die. ;) However, I've learned that fireformed then F/L sized cases have a "memory" (springyness) and over a period of three to five days will actually spring back a bit (.0005" to .001") depending on how much work hardening has taken place. The more the work hardening..... the more the spring-back. A friend in the industry tipped me off to this phenomenon & I really didn't believe it 'til I tried for myself. Now I anneal after every 3rd firing to maintain tight HD SP specs. Some bench resters anneal after every firing. It would seem that once HD SP is set the next challenge is having good control over your brass. Different sizing methods will have different effects on your brass IE: Minimal sizing w/ F/L die, standard expander VS carbide expander VS body die & collet nk sizer VS body die w/ nk die & expander. The variables never seem to end ??? For what it's worth, Dale

[stangfish]

The variables never seem to end
You got that right!

So there are no flaws in your theory just stuff to consider, IE... Will factory ammo shoot in your gun? Does it matter? You can always change it if you don't like it the way it is cause it is a savage. And as gotcha stated, an occasional annealing or changing of the brass is a good thing.

This is a great place to hang due to the experiences of the members. Good luck.