Originally Posted by bigngreen
Matrix Ballistics has a 165gr VLD with around a .650ish BC and a 175gr VLD that sounds like it's around .700 BC. I've been running the 165's out of a 1-10 twist 270 WSM and my buddy has a 270 win, both guns really like them. I can easily shoot them 3050's with my WSM and around 2750 with the Win though we topped out about 100fps faster with each. I've shot quite a few sub 1/2 MOA groups quite aways out there with the WSM but the barrel is out for Nitriding so I haven't gotten to serious with it. Just starting with the Win but in a couple tests the Matrix was just unreal in the accuracy, much better than the 140 Bergers or Accubonds and the Matrix seems real easy going to load unlike the Bergers.
I checked the barrel on mt MK. V and it's a 1:10 twist barrel. Kinda figure the bullet is pretty long, and with the Weatherby there's plenty of room for it <g>! I've always felt the overbore case capacity of the .270mag needed a real heavy bullet to gain any serious use out of it.
Your thoughts on the Berger bullets tend to parallel mine as well. When you got a load that works it's amazing. The hardest ones I ever worked with were their 69 grain LD's. I finally gave them away, and the guy I gave them to uses them for a paper weight. The 88's were not a lot better, but at least they worked.
Suggest you back off on your normal loads on the barrel you sent out for nitride. In the past I've had metal shrink a few tenths, and on the opposite I've had some alloys actually grown as much as nine tenths. A half thousandth smaller bore would be very interesting with a near max load! I started to notice this with the new gas furnaces a few years back, but never saw it with the older ones. Wierd! Did you do the complete barrel, or just the I.D.? A complete barrel should increase the rigidity a little bit