Post #1
A summary of what's below: Enforcer powder can take the 160-grain Barnes GAP bullet to 3200+ fps. I shot into water jugs and some newsprint at that velocity. A lot of words follow; just skip to the pictures if you want.
Warning: The loads described here did not blow up me or my rifle, but they might blow up you or yours. Or they might not. I'm pretty sure I'm working above SAAMI specs with these loads, but I'm not sure. (Translation = I probably don't know what I'm doing.)
The rifle I used in these tests was the M70 bolt rifle with a 26" bbl described on the forum previously. I'm glad it's heavy, because 160 grains at 3200 is at the upper end of the range of 300 Weatherby Mag loads.
Background: Powder selection for making light bullets go fast in the 450B is tricky. As I've stated here before, with 296, Lil'Gun, and 2400, I've run out of case volume before running into signs of excess pressure with the 160-grainers. I don't know about Blue Dot yet. Two years ago in Chap 4 of the 185-grain saga, I listed V-V N105, Ramshot Enforcer, V-V N110, and Accurate No.9 as other possibilities. A few months ago I got some Enforcer, and finally got around to trying it out last week and this. Enforcer is strange-looking stuff, made of very uniform spheres, like little tiny BBs.
To reduce the expense of working with the Barnes 160s, I started with some less costly .451 diameter, 185-grain bullets. Using CCI 41 small-rifle mag primers, I started at 35 grains and worked up at one grain increments. At 50 grains I obtained a bit more than 3000 fps.
I switched to the 160-grain Barnes GAP bullets and loaded them with a side crimp. With a trial of single rounds, these were the 9-foot instrumental velocities I recorded:
50.5 gr - - 3121 fps
51.0 gr - - 3125 fps
51.5 gr - - 3138 fps
52.0 gr - - 3145 fps
52.5 gr - - 3219 fps
I mentioned these results in Hoot's thread on the Barnes XPB when I asked about the water-jug technique for recovering expanded bullets.
Stealthshooter requested a picture of a side crimp, so the image below shows a side-crimped round. The crimp did not make much of an impression because of the solid-copper bullet, and just shows as a line on the case.
(On my web browsers, a left-click on an attached image gets rid of the scroll bars.)