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Subsonic Loads - I have just completed testing of loads out of my Model 1 Sales AR-15, with the following results;
Sierra 220 BTHP W296 - 10.5 gr. Exceeded 1100 fps, occasionally failed to cycle
Sierra 220 BTHP H-110 - 10.9 gr. Exceeded 1200 fps - functioned well
Sierra 220 BTHP 2400 - 8.7 gr. Velocities below 1070 fps - ejected empties, but would not load new rounds
Sierra 240 BTHP H-110 - 10.9 gr. Exceeded 1200 fps (average 1251 out of 5 shots), bolt would pick up a new round but usually did not have enough energy to go completely into battery (used forward assist).
I'm going to try some AA #9 now with the 220's, and try the W296 with the 240's. I was surprised that identical powder charges (10.9 gr of H110) produced higher velocities with the heavier bullets - somewhat counter to what usually happens.
Miker
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