Bobby, Did you get a chance to try the 6 mm 80 gr NBT bullet any more? Is it good enough to replace the 80 gr Sierra SSP and a "do everything" load? I bought a bag of NBT factory blems a few months ago, but just now got around to loading some up. Accuracy and velocity look pretty comparable to the 80 Hornady SSP and, your previous favorite, the 80 gr Sierra SSP. I was shooting off sandbags instead of my usual set up w/the bipod; I think the NBT will shoot better when try it later w/ the bipod. Almost all my groups that day had the 1/3 shots vertically displaced. Here were the results from my 6X50R Bellm, using Hirtenberg brass, Rem 7 1/2 primers, 80 gr NBT (0.02" off the lands), Leupold 2.7-8.5X scope, and H4895 (only powder I've tried thus far):
28.5 gr/2575 fps/1.3"
29.0 gr/2643 fps/2.7" (two shots nearly touching)
30.0 gr/2722 fps/1.1"
One of the 30.0 gr loads was slightly sticky, but it was also 97 deg. Think I'll try some loads w/ 29.0 gr and 29.5 gr.
Gary T.

Gary-Well, I did run the 80 grain NBT through the paces a bit but am still not 100% sold on it. The MV from the 15" 6mm-.223 barrel averaged 2705 fps, and accuracy with the H335-based load is superb and consistently in the 0.5 MOA range.

In taking several coyotes, performance has been splendid. Shots ranged from app. 70 yards to app. 230 yards. Field autopsies revealed excellent tissue damage, and bullets exited in each case, including a couple of quartering shots. That's the good news...

But on a couple of 'coon and a few armadillos, I got less than stellar results. On 2 coon (65 and app. 110 yards), I got very little expansion and minimal internal damage on behind-the-shoulder shots. However, to be fair, I must add that these bullets were from an older lot. On another coon, and with newer bullets, I got a wicked, baseball-sized exit on similar shot presentation, this time at a range of app. 120 yards.

To the other extreme, however, I did not get an exit on 2 armadillos, and both were taken at around 85-90 yards. In each instance, the entrance (again behind the shoulder) was quarter-sized or larger. I did not attempt to recover the bullets, but simply turning the 'dillos onto their side resulted in liquified innards pouring out.

I want to try the 80 grain Ballistic Tip a bit more before using it on anything larger than a coyote. Until then, I'll stick with the time-proven Sierra 80 grain SSP. It provides eye-popping groups with monotonous regularity, and its terminal performance on game is so consistent that it is boringly predictable.

By the way, I've found that with the 80 grain BT (in my barrel, at least) best accuracy comes with the bullet backed a bit farther off the lands than I usually prefer.

Gary-I only ran a few through the test medium. I don't have the results in front of me, but from what I remember, the weight retention was in the neighborhood of 70 percent. The Sierra 80 grain SSP is generally 80-82 percent in this particular testing.