http://bulletin.accurateshooter.com/2011/03/new-ar-comp-powder-from-alliant-details-revealed/New AR-Comp Powder from Alliant � Details Revealed
Here�s the latest info on Alliant�s new AR-Comp powder. We had a chance to talk with Dick Quesenberry of Alliant, who revealed more details about this new propellant. First, Dick explained that AR-Comp is an advanced re-formulation of Reloder 15, a double-base Bofors powder. There are changes to internal and external chemistry to provide much better pressure/velocity stability across a wide range of temperatures.
AR-Comp Offers Uniform Velocities over a Wide Temp Range
Tests were done with .223 Rem and .308 Win ammo, loaded with AR-Comp and maintained at temps from -20� F to +160� F in a controlled test center. The ammo itself was heated or cooled to targeted temps before testing. Across that entire range of temperature, -20� F to +160� F, the ammo loaded with AR-Comp showed a variation of only 20 fps in muzzle velocity. The primary bullet type tested was a 77gr .224 bullet and the secondary was a 175gr .308 bullet.
Burn Rate Like Varget: Though this is a reformulation of Reloder 15, the burn rate of AR-Comp is slightly faster than Reloder 15. Alliant told us: �Reloder 15 is slightly slower, in burn rate, than Varget. The new AR-Comp, with the enhancements, ended up slightly faster than Reloder 15, so it is now very close to Varget in burn rate�. This is the result of the �tuning� of the powder to be much less temp-sensitive.
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More info at the link above...
