Re: 264 win mag
There are a few of us on here shooting 264s. Most of us have at least one 264 Sendero II. I've worked up a load using 140g SMKs that, when I'm doing my part, will print sub-.5" 3 shot groups. When I'm not doing my part I cuss a lot and wonder WTF is going wrong.
Our rifles have 1:9 twists. I've bought both Berger 130s and 140s and will begin load development one of these days. 1sikpuppi and JamieD are both 264 shooters and I think thers'a couple more somewhere.
As far as the short throat thing, you're the second person I've heard that from. Makes me wonder about my rifle.
Look forward to talking with you further. One last thing - in case you don't know it, 264s can be VERY tricky to load for.