First time poster with a fire forming question

[tonyben]

Hello, I think this is my first post here but I have been lurking here for a little while. I want your input with regard to fire forming virgin brass. I have a custom built M14 with a non-chrome lined 22' barrel. It headspaces at 1.631'. The M14 is brutal on brass and it is only safe to fire casings about 5 times without the potential for case-head separations.

I envy you guys who can get 30+ reloads with the same brass.

This rifle only has 170 rounds through it and I just bought some virgin Winchester brass. I have been resizing various cases to ~1.627' and would like to start re-sizing to 1.628'. My new batch of brass headspaces at about 1.621'. Do you all think it's worth it to fire form the cases using the pistol powder/media/crisco method?

I am thinking this would get me the proper sized brass without stressing the case head as if I was shooting full loads. 308 brass is expensive and I have been taking pay cuts at work, so penny pinching is a way of life until my job situation improves.

The 308 is a new caliber to me so I haven't built up a stockpile of brass yet. I only have 100 unfired cases and want to make them last. Currently, my groups are okay and I am beginning to incorporate more control methods to my reloading to achieve better accuracy. This rifle is built with top quality parts but is in pretty much a bone-stock configuration with only a few accuracy mods.

My stock is not glass bedded, nor is my gas cylinder unitized and I can get ~3' groups on a good day with iron sights at 100yds. I have no scope and I am using GI standard sights. So far, I have been using mixed headstamps with IMR 3031 and 168gr SMK's. I finally invested in some IMR 4895 and 100pcs of WInchester brass from the same lot and will be working up my first consistent loads from here.

Tony.

 

[davek]

I don't know why you would want to fireform brass for a m1a and don't know what help it would be for accuracy in this rifle . As you stated there is a limited amount of life in a m1a, gasgun case, I only reload 2 or at the most 3 times of a oncefired, ie, lakecity case, that is a max of 4 firings, Try 42.0g or 41.5g of imr4895 as a start in some brass with a 168 sierra and use it as a baseline, please watch for pressure and load accordingly, be safe. This should get you started.
davek.

 

[rayjay]

I would fireform with greased cases. I even do this on my PPC or 30BR when fireforming brass that is a tight fit in the chamber.

 

[panhandle]

I've tried different ways to fire form and the one that works the best for me is to expand to necks up to the next caliber and then size the neck back down with the sizing die until the bolt will just close on the case. This gives a false shoulder for case and the firing pin can't move the case forward. Load as normal and work up your load and go shooting. I have done this on 3 different p-dogs guns and formed cases as I'm shooting dogs. This method has been easiest for me to deal with, I like things simple.

 

[tonyben]

Thank you for the replies gents. I just had an epiphany. I can turn off the gas system and basically shoot the rifle like a bolt gun which would fireform my case without stressing the case head during extraction. This should give me an extra firings on the cases without the risk of a case-head separation. I will have to compare accuracy differences later with the gas system turned on.

Thanks again, Tony.