Neck sizing vs full sizing question.

[Condition1]

18 hours ago, Catch-22 said:

Simples really.

Take your bolt out, remove the firing pin/striker and remove the ejector too. It’s fine to keep the extractor claw.

Screw your F/L die into your press until it contacts your shell holder. Now back the die out a couple of turns, so it won’t fully size all of the case back down to SAMMI spec as that’s too much.

Now insert your bolt (minus the firing pin/striker and ejector you removed) and the handle should just flop down without any resistance.

Take a piece of fired brass, lube it, place in press and size it. Remove brass, wipe lube off and place brass into your rifle’s chamber and gently close the bolt. If the bolt doesn’t fully close, or it closes with some force/resistance, the brass needs to be sized down further.

Extract brass, lube and place in press. Turn die DOWN (so sizing the brass more) just a tad (0.01 or 0.02). Size the brass again. Now try it again in your chamber.

Repeat just until your bolt will flop down like it did with no brass. This tell you that you’ve bumped your shoulder back just enough so the brass has minimal clearance but is guaranteed to chamber freely so you don’t get chambering issues. It’s also been sized just a minimal amount, no where near SAMMI spec. Use your calipers and Hornady headspace gauge to record the optimum headspace bump value.

Ive found this to be the most accurate way of measuring my chamber headspace and minimum case bump required.

There was an excellent and simple vid from Aron Wheeler (gunsmith) showing it all but I cannot find it on YouTube sadly.

That makes sense also. Yes pretty simple.

[Condition1]

18 hours ago, John MH said:

Well if you want to be really specific its best to try several sized cases as each will probably be slightly different (more or less spring back even if annealed) and opt for the average but we are probably talking less than 0.001" here and the ability to consitently and accurately measure that difference starts to get difficult.

getting quite complicated now  and probably down to a level I don’t have the stamina for. I’d probably start losing track going into this much detail.  But baby steps, I’ll experiment with die insertion or maybe she’ll holders.

I have never annealed, don’t really want to start as it looks expensive and more time consuming.

we are probably heading into the realms of diminishing returns for my application. I don’t compete or anything, I shoot for fun,  I do enjoy my bolt actions and plan to shoot more this year with them but PSG and lever actions take a lot of time.

[DeLaRue]

Like a lot of things in life it all seems very complicated but much simpler when you actually do it......Good luck, I'm sure you'll be fine! 👍

[palo]

This is a good video on setting up your full length die 

[Condition1]

Thanks I’ll take a look