Small Rifle Primer (SRP)
Many competitive shooters prefer Small Rifle Primer pockets (SRP) because they experience longer primer pocket life due to the increased material in the head of the case. There is also a belief that Small Rifle Primers produce a more consistent ignition. Some people even report better groupings and lower velocity spreads.
However, SRP are not recommended for shooting in extreme cold or hot temperatures. And Small Rifle Primer Brass sometimes requires the firing pin on your gun to be bushed. This depends on your rifle and your bolt. If that is not done, you risk getting pierced primers.
To make sure you don’t have any problems shooter should talk to their gunsmith and understand what their rifle is set up for before using SRP brass.
NOTE: If you plan to load above SAAMI max pressure and are concerned about primer-pocket leak, Peterson recommends you try their .308 Winchester Small Rifle Primer. While they do not suggest loading over SAAMI max pressures, their small primer pocket .308 Winchesters have proven to hold up over SAAMI max pressures when tested in their universal receiver.
Warning: Only use Peterson Cartridge Co. casings in firearms in good condition, designed, marked, and chambered for this cartridge. Do not use Peterson Cartridge Co casings for “fire forming” or any other purpose other than what they were designed and tested for. Peterson retains no responsibility for the enclosed casings if they are used outside of the manufacturer’s recommendations.