load development using new brass

[coues7]

I think I already know the answer but I'm trying to work up some loads and only have so much of two types of brass....FGMM and NEW Winchester brass (never fired). I've loaded up 10 rounds of each load that I'd like to test, using the ladder test. I'm out of my once fired FGMM so all I have left is lots of the Winchester stuff.

I guess the only concern I have is pressure changes due to the brass being fire formed into my chamber <span style="font-weight: bold">AND</span> internal volume differences between the two brass brands leading to pressure changes.

I hate to throw out 60 pieces of FGMM brass. Am I over thinking it?

 

[260shtr]

Re: load development using new brass

If you have a good load with Fed brass, run a ladder with the Win brass to the same velocity and check the accuracy. Tweak for accuracy.

 

[coues7]

Re: load development using new brass

I'm trying to find a load that shoots sub MOA out of my GAP.....the 190gr FGMM wasn't doing the trick.

I don't have a good load with the Federal brass to work with.

 

[kirkhamg]

Re: load development using new brass

The load in FC brass will be different than the Win brass.

An interesting phenomenon is that for as well as the Fed GMM shoots the first time, it is not highly favored among hand loaders.

I have a good supply of once fired FC and GMM brass, and have tried developing a couple of different loads, only to get erratic, odd, or otherwise unacceptable results.
Switched to Win brass, and they "magically" dialed right in.
Have also read of others having similar results.

 

[coues7]

Re: load development using new brass

Very interesting. Should I just dump the FC brass and move on?

 

[Agent Ronin]

Re: load development using new brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coues7</div><div class="ubbcode-body">Very interesting. Should I just dump the FC brass and move on? </div></div>

I've had similar experiences with Federal brass when trying to load match loads.

I just feed those cases to my M14 and HK91 with good old fashioned FMJ's without worrying about how beat up they get.

 

[wirehand]

Re: load development using new brass

Save the FGMM brass for anealing practice or dummy rounds.

IMHO it's way to soft for reloading.

After seeing some case head seperations on the third reload, I am to paranoid to use it in a gas guns.

 

[coues7]

Re: load development using new brass

So if I'm going to dump the FGMM brass is it ok to use brand new never fired Win brass? Will my loads behave differently in new vs. once fired (after I start using the it once it's fired)? By the way this is the 190gr SMK stuff

 

[wirehand]

Re: load development using new brass

Of course it is posibble that your accuracy will change with the Win. brass and even between virgin and fired cases.

This just depends on how centered your accuracy node is.

You are way ahead by useing better brass.

When I first used virgin lapua brass it out shot FGMM brass at all powder increments.

 

[coues7]

Re: load development using new brass

I guess now becomes what do I do with the 40 rounds I've already loaded using the FGMM brass? Pulling's not a problem but chucking/selling primed cases is a pain

 

[dan46n2]

Re: load development using new brass

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: coues7</div><div class="ubbcode-body">I guess now becomes what do I do with the 40 rounds I've already loaded using the FGMM brass? Pulling's not a problem but chucking/selling primed cases is a pain </div></div>

Deprime them and save the primers.