I need a little research assistance. I'm trying to move away from our current rifle duty round to one of the rounds suggested by Dr. Roberts. We have 1/9 twist AND 1/7 twist barrels, 16" and 11.5", so I'm looking at the Federal 64 grain TRU as a probably replacement. It'll will work in both barrel twists and I've not heard any bad things about it (other than some reports of bullet back-up, which I hear has also been rectified). And the concern of lead build up on the feed ramp during heavy shooting days due to the exposed lead.
We currently use the Hornady 60 grain TAP. I know of antecdotal evidence that suggests this round is not good for LEO work. I've also read here and on TF about ballistic tip ammo not being ideal.
So on to the matter at hand. I know Doc's list of recommended rounds and I believe his work is outstanding. I used his research extensively when justifying a transition away from laminate vests to woven aramids for my PD. So all I really need is research assistance to prove to the "gun's and sandwiches crowd" that the 60 grain TAP isn't ideal. I wish 75 were an option, but with the 1/9's....well you know the deal.
Specifically I'm looking for a link, report or quote about the 12" minimum pentration recommendation. That should be sufficient to supplement what I already have.
However, feel free to throw out anything that you think may help. Doc has done the hard part (making the recommendation). This is one of those situations where I know it to be trusted and true, I just need to work backward a little to solidify the position.
Edited to add: I think it was Dr. Fackler who recommended the 12" minimum, but I can't seem to find it.