Post by wfa on May 16, 2015 12:52:33 GMT -8
Ever notice that "plans" never end up the way you "plan"? I ordered an 18" BHW barrel in 300 Blackout simply for supersonic loads, and it does the job, but no better than my 16" 5R barrel (OK, it's a little bit faster, but not a whole lot). Both shoot nice round, tight, groups.
ANYWAY, SPS had a sale on Nosler 190gr HPBT Comp bullets at an excellent price, made "more excellent" with my "retired military" discount. I loaded up a few rounds for the 16" 5R using the "standard" load of 11.2gr of AA1680 that I've used with the MBC 245 lead bullet; I was going to "work down" from there. Well, the first 3 rounds were touching at 25 yards, the velocity was 1050 fps - SD was 2! Three rounds don't prove much more than "proof of concept", so I loaded twenty. Same results with 10 shots (all touching, .75" edge to edge). Function was fine, but no bolt hold back - no big deal. Now I had my "standard load".
Then I made the mistake of "wondering" how they would do in the 18" BHW. Velocity was 1080 fps, SD was a tad bit greater, but there was only one visible hole in the target. I made the short walk to the target board and it was clear that the seven (three of the remaining 10 were used for sight adjustment) of them had gone through the one 3/8" hole. Bolt hold back was 100% using two different magazines.
An interesting "factoid": Velocity is almost identical to what I see with the 245gr MBC lead bullet in the 16" 5R (that bullet will not shoot in the BHW). By "rights", even with the increased friction of the jacketed bullet, the 190gr SHOULD be faster (and supersonic). The more you shoot, and the older you get, the less you "know"!
ANYWAY, SPS had a sale on Nosler 190gr HPBT Comp bullets at an excellent price, made "more excellent" with my "retired military" discount. I loaded up a few rounds for the 16" 5R using the "standard" load of 11.2gr of AA1680 that I've used with the MBC 245 lead bullet; I was going to "work down" from there. Well, the first 3 rounds were touching at 25 yards, the velocity was 1050 fps - SD was 2! Three rounds don't prove much more than "proof of concept", so I loaded twenty. Same results with 10 shots (all touching, .75" edge to edge). Function was fine, but no bolt hold back - no big deal. Now I had my "standard load".
Then I made the mistake of "wondering" how they would do in the 18" BHW. Velocity was 1080 fps, SD was a tad bit greater, but there was only one visible hole in the target. I made the short walk to the target board and it was clear that the seven (three of the remaining 10 were used for sight adjustment) of them had gone through the one 3/8" hole. Bolt hold back was 100% using two different magazines.
An interesting "factoid": Velocity is almost identical to what I see with the 245gr MBC lead bullet in the 16" 5R (that bullet will not shoot in the BHW). By "rights", even with the increased friction of the jacketed bullet, the 190gr SHOULD be faster (and supersonic). The more you shoot, and the older you get, the less you "know"!
