Re: 308 Sub Sonic Load question
Just got back again from the range. Loaded up 5 rounds of each starting at 11gr-11.8gr in .2gr increments. Rounds were all over the place. The 11.8gr load seemed to be the sweet spot for accuracy. I dont see any evidence of Key Holing, so I guess my barrel is stabalizing the bullet. Velocity was 1128, 1090, 1109, 1121, & 1074. Yea, thats a big ES, but here is a pic of the grouping with 5 shots at a 2" target at 100 yards. There are 3 bullets within the grouping on the left.. Yesterday at 12gr, I was getting the "crack". Should I be getting better groups than this or should I accept this? The rifle is capable of 1/3" groups when I do my part. But shooting Subs, does accuracy go down? Whats an optimal velocity to be around? Seeing as how 1150 is where the "crack" will be heard, is it common to stay around 1100fps, or more so around 1000fps? Another thing I noticed was there was more than a normal around of soot around the case neck. Is this another issue? lol
For those that are curious about my Velocity about my other loads, here ya go. These are Trailboss, Win brass, Fed 210M, Hornady 180gr RN FB bullet, off the lands .010.
I dont understand why the velocity was lower with higher GR loads.
11gr - 1096, 1050, 1031, 1027, 987
11.2gr- 1002, 1074, 1040, 1009, 1019
11.4gr- 1090, 1053, 1036, 1030, 1029
11.6gr- 1099, 1091, 1055, 1067, 1067
11.8gr- 1128, 1090, 1109, 1121, 1074