I am a big fan of both of these rounds. I will say however, and this is not a bash on light ultralight bullets, its simply a fact, the STW will be more consistant and accurate with a heavier bullet. 85 grains is just not enough bullet weight to get a consistant powder burn with a case capacity of this size with the powders that would be appropriate.
I really recommend at least 100 gr bullet weights in the STW. You loose a bit in velocity but you will still be pushing 3800 fps very hard and perhaps a bit more. Believe me, a 100 gr bullet at +3800 fps is most impressive.
If you really want to shoot the 85 gr bullets, I would highly recommend going with something like a 25 WSM or 25-264 Win Mag class chamberings. They will work much better with this bullet weight.
Again, not bashing the hyper velocity thing, just telling you that if you want consistant velocities out of the big STW case, you will be much happier with the 100 gr and heavier bullets.
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