Re: 6mm-06 or AI version info. ?
I think your velocity predictions are realistic. I was getting 3450 fps with the 107 gr ULD RBBT in my 224 Allen Magnum on that same case so I would imagine jumping up to a larger 6mm bore would easily get near 3500 fps. I was testing in a 27" Lilja.
Just more velocity then the bullets could handle with their thin jackets.
I would think a 1-8 6 groove would be about perfect for a 120 gr 6mm at these velocities.
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