When figuring the maximum bullet length that a twist will stabilize and using a Ballistic Tip bullet do you deduct the plastic length?
My way of thinking is that the density of the plastic is so low that it can be disregarded for twist. If that is correct, then a 30 cal Accubond could be thought of as a hollow/flat pointed bullet 0.2 shorter than the actual AOL.
From what I have seen and tested, you must include the entire length of the bullet no matter what the mass of the tip is. Length is length. May be simplistic but that is what I have seen from testing. Specifically testing 22 cal tipped bullets.
I have seen on several occasions where a 1-14 twist did not accurately shoot the 55 gr Baliistic Tip or 60 gr V-Max out of a 223 or 22-250. In fact groups were in the 3/4 to 1 moa range. Not bad but not great.
In comparision, those same 1-14 twist barrels would shoot the 55 gr hpbts very well and the 50 gr Ballistic Tip and V-Max into sub 1/2 moa groups as well as the 40 gr Ballistic Tip and V-max.
I am not saying that all 1-14 twist barrels will not shoot them well but several will not.
In comparision, I have barreled many rifles in 223 and 22-250 with 1-12 twists that shot the 55 gr BT and 60 gr V-max into sub moa groups as well as all the HPBTs and ligther weight bullets as well.
I do believe the plastic tip makes a difference in minimum twist required for a given bullet.
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