My COAL looks like the SAAMI Max of 3.340” for the unaltered M70 458 Winchester.
So my velocity hopes out of the 22” barrel, shall be lower than your lowest achievement. I will be satisfied with 2300 fps. Anything over 2300 more happy.
At 2300, based on a BC of .410, I should still be slightly about 1900 fps at 200 yds with minimal trajectory concern.
