Newb Question: Primers for a 308 Winchester Semi?

[breuerp]

I'm brand new to reloading and I've some confusion on primer selection for a semi-auto (e.g. not bolt action) 308 Winchester rifle. I've read that auto rifles require the use of CCI #34 primers to prevent "slam fires." The same location mentioned that #34 is considered magnum primer so a few less grains than recommended should be loaded.

- Do auto 308 rifles required #34 primers to prevent slam fires?

- As long as I'm within the recommended powder load for a 308 Win(*NOT* at max load), can I load per the reloading manuals?

- Both of the reloading manuals I have (Lyman 49 ed and Hornady 9th ed.) provide numerous loads for the various powders and bullets but no variation for the primer used. Does this matter as long as I use a large rifle primer?

Thanks!

[wgj3]

You have a healthy respect for this endeavor, great start!

#34 primers definitely NOT required

The manuals cant cover every single combination, but as long as you are starting a bit below max charges and using a projectile of same weight and composition (cant sub cast for jacketed), you should be perfectly safe.

You are absolutely on the right track. The biggest issue with self-loading .308 is appropriate cartridge dimensions, overall length, headspace, case length, case-body diameter, etc. Some platforms more fussy than others.

Second is appropriate pressure curve and gas volume, determined primarily by powder selection, and again some actions pickier than others.

[breuerp]

You have a healthy respect for this endeavor, great start!

#34 primers definitely NOT required

The manuals cant cover every single combination, but as long as you are starting a bit below max charges and using a projectile of same weight and composition (cant sub cast for jacketed), you should be perfectly safe.

You are absolutely on the right track. The biggest issue with self-loading .308 is appropriate cartridge dimensions, overall length, headspace, case length, case-body diameter, etc. Some platforms more fussy than others.

Second is appropriate pressure curve and gas volume, determined primarily by powder selection, and again some actions pickier than others.

Thank you! Case gauge and calipers are in continuous use. The plan is to load a batch of 20 checking each round. Once I'm comfortable having checked/fired those 20, I'll go to batches of 50 checking the first three and then random sample. Who knew that my probability and statistics would come in handy?