Well, I ended up building a 6BR on a 1/14 twist Hart by Dowling. It has been extremely accurate with 2230 powder (thus far the only powder I have tried) and the 55 grain NBT. I was getting craters on my primers at 3750 fps so I sent my bolt to Gre-Tan and had the firing pin hole bushed. From there I was able to achieve 3920 fps out of my 26" barrel. One more TENTH grain of 2230 powder made the velocity jump to 3980 so I settled on 3920 fps. Accuracy never changed. Pretty much one hole.
I have been a bit surprised at the performance of the 55 NBT at 3900+ in the field. My first critter taken was a coyote at 185 yards or so. He was DRT but I expected to see a huge exit wound but did not see any such. I have shot a number of S Texas hogs as well. As long as I brain them, they are DRT. Anything else and they run off. A cull buck, head shot at 170 yards as well as a decent 8 pointer neck/spine shot at 225 yards were also cleanly taken. This little cartridge is a real killer as long as you can get steady enough to deliver the little pill right where you should.
I have been a bit surprised at the performance of the 55 NBT at 3900+ in the field. My first critter taken was a coyote at 185 yards or so. He was DRT but I expected to see a huge exit wound but did not see any such. I have shot a number of S Texas hogs as well. As long as I brain them, they are DRT. Anything else and they run off. A cull buck, head shot at 170 yards as well as a decent 8 pointer neck/spine shot at 225 yards were also cleanly taken. This little cartridge is a real killer as long as you can get steady enough to deliver the little pill right where you should.
