I have a bullberry 22 inch barrel with, I believe a 1-12 twist. Bullberry barrels are great, I have quite a few. 223 AI is great, but since I don't do too much varmiting these days, it doesn't really do anything any better than my bullberry 223 rem barrel. It shoots great, but doesn't get used to splatter chucks like it should.
contact me for more info if you like.
regards,
graycg