So I was fiddling with the 6.5x55 most of the evening yesterday, and a little with the 270.
I couldn't get the .270 to lose it's grip on the shell casing at all. But it didn't exhibit the problem very often in the field. Just once with me on my first shot, but the rest of the time it didn't have any issues.
Most of my attention last night was on the 6.5x55, since my brother said it happened to him quite a bit. I saw it happen a couple times. First I was feeding and cycling empty brass, then I put together some dummy rounds, because empties don't feed very well.
I was cycling things very slowly and deliberately at first, and I couldn't make the claw lose it grip on the casing at all when moving slow and deliberate.
Then I started cycling it faster and faster. At one point I was just moving the bolt all the way back and all the way forward quickly without bring the bolt handle down. [This is how I unload my Brazilian Mauser Sporter which has a blind magazine.] As I did this, there were 2 times that the 3rd round fell off the bolt face and didn't get to the ejector. Both times it was the 3rd round.
So I'm not sure what to make of this. From what I can tell, it definately has an issue, but I can't make it consistently reproduce that issue. I could just ignore it, but then I'm sure the issue will present itself right when the buck of a lifetime shows up.
I do know that my handloads are hot. Lots here would say too hot, but I don't think they're too hot. Primers are definately flat, though. Would a hot load cause the claw to lose it's grip?
Maybe the brass is just a little stuck, and the claw slips over the rim? I've not ever had the case left completely in the chamber, it's always at least part way out, and can be grabbed with fingers and removed.
Should I try taking off the extractor and bending it a bit?
I'm still stumped.