Owner's Manual/ Brochures
The OMEN is optimized to use quality ammunition. Do not use ammunition that exceeds maximum chamber pressure recommended by SAAMI (Sporting Arms and Ammunition Manufacturers Institute). The maximum pressure is 64,000 PSI, Piezo measured.
The maximum COAL (Cartridge Over All Length) that can be used in the OMEN is up to 3.50 inches. You must check your chamber dimensions before loading ammunition beyond SAAMI length.
There are many different manufacturers of ammunition and loads for the .300 Win. Different ammunition, bullet weights and powder combinations will cause varying degrees of accuracy and performance of the rifle.
Lighter loads, and bullet weights may cause the rifle to not lock the bolt back on the last rounds. Lighter loads can be hot loads and could cause cycling issues, pierced or blown primers.
Really hot loads or heavy bullet weights may cause overgassing, pierced or blown primers.
Soft primers, or loose primers may cause blown or "dropped" or pierced or blown primers. The OMEN is designed to perform the best with military-grade hard primers.
Ammunition not to be used in the OMEN:
Any ammunition that shows excessive pressure signs such as flattened primers, blown primers, pierced primers
If your ammunition is blowing or piercing primers, discontinue shooting. Completely fieldstrip and clean rifle. Replace firing pin if you have pierced primers. Use different ammunition.