Overpressure?

[rudar]

Hey all,

I'm working up a load for my .270 Winchester using 130 grain hornady interlocks over Hodgon 414. I've used from 50 to 53 grains of powder in 1 grain steps. Lee lists 53.5 grains as the max load. Unfortunately, I didn't really notice this until I was depriming, so I've mixed up the brass from the different loads... Do these primers look like they're showing overpressure?

(the ones on the left look fine, but the ones on the right?)

After removing primers:

Or, well, I guess it's clear that they are showing signs of pressure being a bit flattened like that, so the question is are these primers telling me "You're getting close, and shouldn't go any hotter", or are they telling me "DANGER! DANGER! Back off a grain or two RIGHT NOW!"?

I think I was getting better groups from 52 and 53 grain loads, so...

 

[Eagleye]

I don't see anything there that would make me back off a load. There is still a radius on the primer, but definitely the one on the right shows more flattening than the one on the left. still, no signs of "excess" pressure. BTW, whose primers are you using? Regards, Eagleye.

 

[John Y Cannuck]

They are showing an increase in pressure, but not IMO too much. You are however closing on max.
On the photo's alone, I'd stop there.
No doubt you could go a bit further, but perhaps not safely (certainly not a grain at a time!) but I have to ask if it's shooting accurately at that level, why push it?

 

[rudar]

OK, cool, thanks. I don't see any need to go further, but it does seem to be shooting better at the warmer loads than the cooler ones, so I'm happy that I don't need to back off... And I really wanted to just pick an OK load and start some serious practice from field positions for the next few range trips. I can mess about with half- or ever quarter-grain variations to find the best load after hunting season

Oh, and CCI primers.

 

[CyaN1de]

If it's any help, I have seen (while load testing my own rounds) primers flatten with what was supposed to be a medium load and then "unflatten" again as the load got a little hotter and then back to flat when it was reaching pressure max.