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Got a weird one, and looking for explanations that I may be overlooking.
My 18" AR15 (.223 wylde) loves the 73 grain bergers and the 75gr Hornady HPBT. Easily sub 3/4 moa, and often 1/2. Whats weird is how damn slow they are compared to published velocities.
Example:
73gr Berger w/ 24.5 grains of Varget- avg 2670 FPS
Bergers MAX load is 23.3 with an estimated velocity of 2840.
Thats right, Im 1.2 grains over max (no pressure signs whatsoever) and coming up almost 200 FPS slower with an 18" barrel.
The Hornady comes up almost 300 FPS slow using the max published charge.
All other guns I test, the chrono results are rather consistent with published estimates.
The only thing I can think is that enough pressure is "leaked" to cycle the action, and the published velocities in Bergers manual are using a longer barreled bolt gun.
My 18" AR15 (.223 wylde) loves the 73 grain bergers and the 75gr Hornady HPBT. Easily sub 3/4 moa, and often 1/2. Whats weird is how damn slow they are compared to published velocities.
Example:
73gr Berger w/ 24.5 grains of Varget- avg 2670 FPS
Bergers MAX load is 23.3 with an estimated velocity of 2840.
Thats right, Im 1.2 grains over max (no pressure signs whatsoever) and coming up almost 200 FPS slower with an 18" barrel.
The Hornady comes up almost 300 FPS slow using the max published charge.
All other guns I test, the chrono results are rather consistent with published estimates.
The only thing I can think is that enough pressure is "leaked" to cycle the action, and the published velocities in Bergers manual are using a longer barreled bolt gun.
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