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**Unclenick** · August 23, 2011, 09:31 AM

A quick ballistic program run-through says you'll need about 2500 fps on the 208 to keep it above the transonic range (usually given as around Mach 0.95 to Mach 1.25, but there is opinion wiggle in that based on different bullets) all the way to 1000 yards at U.S. Army Std. Metro. conditions. Going to be tough to get that in the .308 case without going over the standard SAAMI pressures.

Some guns can handle that and some can't. I don't like running hot if I can avoid it and still get accuracy, just because it increases throat erosion rates and general fatigue of the steel.

August 23, 2011, 09:31 AM	#15
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	A quick ballistic program run-through says you'll need about 2500 fps on the 208 to keep it above the transonic range (usually given as around Mach 0.95 to Mach 1.25, but there is opinion wiggle in that based on different bullets) all the way to 1000 yards at U.S. Army Std. Metro. conditions. Going to be tough to get that in the .308 case without going over the standard SAAMI pressures. Some guns can handle that and some can't. I don't like running hot if I can avoid it and still get accuracy, just because it increases throat erosion rates and general fatigue of the steel. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle