I just wanted to share the results from an OCW test I ran using Hornady's 80gr AMAX and Ramshot TAC powder. The tests were run using Hornady brass, Remington 7-1/2 primers and with the bullets seated .020" off the lands. The charges varied from 22.0gr to 23.2gr (which is just under the max load I found). Rifle is a Rock River NM A4 with Wylde chamber and 1:8 twist.
It looks like the OCW for my rifle is between 22.4 and 22.8gr. I was surprised to see how much the POI changed with the 23.2gr charge. I didn't get a chance to chrono any of the loads (weather was overcast) but the load data says velocity should be between 2,550 and 2,600 fps. Next I'll start playing with seating depth to see if I can get the groups to tighten up a bit and also get some chrono data. If I can get some good groups, this will be my new XTC 600 yard load.
It looks like the OCW for my rifle is between 22.4 and 22.8gr. I was surprised to see how much the POI changed with the 23.2gr charge. I didn't get a chance to chrono any of the loads (weather was overcast) but the load data says velocity should be between 2,550 and 2,600 fps. Next I'll start playing with seating depth to see if I can get the groups to tighten up a bit and also get some chrono data. If I can get some good groups, this will be my new XTC 600 yard load.
