Benchmark 2 for 308

[dant]

Hi, does anyone have any experience in using Benchmark 2 powder for .308 ? Im hoping to use 150gr speer hot core bullets.

 

[georgehwbush]

experience no. but i feel like it's too fast burning for the 308. especially from a non-autoloader.

while hodgdon does specify that if you use "light match bullets" it will work in the 308, the 150gr speer hot core doesn't exactly qualify.

feel free to try it, but i think you would like a slower burning powder better, and probably get better performance also.

see a "propellant burn rate chart" for more info.

something closer to the 4350's would work better.

 

[Unclenick]

Dant,

Welcome to the forum. Please pop over here and introduce yourself.

BM 2 is ADI's designation for what Hodgdon sells as just Benchmark. It is slower than BM 1, which is an H4198 alternate, but it is quick relative to most .308 powders. Hodgdon's data shows one load for the 150-grain Nosler Ballistic Tip which would likely work with your Hot-Core bullets. It is 39 grains to start and 43 grains maximum in a Winchester case (generally the most generous interior volume of all the brass on the market) and Federal 210M primer. Other brands of brass may require knocking the loads down a grain or so for matching pressure.

The Hodgdon Velocity and Pressure (V&P) barrel, which is a 24" barrel with a nominal bore and a minimum chamber size, got 2752 fps (measured with the midpoint between screens of an optical chronograph at 15 feet) average velocity with the maximum load. By comparison, AR2208 (sold in the U.S. as Varget) got 2937 fps from the same barrel. This is because its burn rate is most appropriate for this bullet weight. There was no 4350 data because it is a bit too slow and low in bulk density for the 308W with this bullet weight, whereas it works well in the larger 30-06 case if you compress the maximum load.