7 SAUM Hot loads, when they shouldn't be hot

[rman1]

Doing load development for a 7 SAUM, in a Model 7. Get all sorts of bolt face and extractor marks on the brass, at minimum loads. Not sure what can be causing this? Will grab a box of factory ammo, and the chronograph, to try and get some answers.
Any further thoughts?

Thanks!

R.

 

[milo 2.0]

You say minimum, what is it?
Is your bolt face covered with brass?

 

[Bear24]

As I understand you can get pressure signs on the low end of charges due to flashover of the powder not filling the case. What powder and charge are you seeing this with?

 

[rman1]

Lots of brass sign on the bolt face. Just to make it clear, I'm not new to reloading, but I have never seen this with minimum charges before.
Two loads, with 140BT's. 2.825 COAL. All cases 99% plus fill rate.
61 grains of 7828SCC. Quickload states around 52,000 psi.
62 grains of RL22. Quicload states around 53,000psi.
Remmy 9 1/2 primers.

Thanks!

R.

 

[milo 2.0]

I have 2 7saums, it doesn't seem to be hot. Have you had the gun long, fired it before? If the brass on the bolt face is built up, could be just a rough bolt face, which would give a premature pressure signs, a pic might help.
Are you getting the round ejector hole mark?

 

[rman1]

Hello. Just picked it up. These are the first firings. I'll clean off the bolt face, and try again.
Yes to the ejector mark.
Thanks.

R.

 

[wvlapua]

Are you in the lands and is your brass too long?

 

[rman1]

No where near lands. Brand new brass, sized and trimmed.

R.

 

[milo 2.0]

Hodgdon's web data says you're OK. Chrono the load and see what velocity is. Ejector marks don't lie. Every barrel is different.

 

[rman1]

The chronograph is next, for sure.

R.

 

[milo 2.0]

You have any H1000? Maybe something slower might work. Do keep us posted.

 

[rman1]

I'll clean off the bolt face, and do the chronograph thing. I'm thinking it isn't the powder. The chrony will tell me what I need to know.
Thanks.

R.

 

[timelinex]

My 110ba ALWAYS leaves a swipe mark on brass. I have used both hsm brass and lapua brass, and I have done everything from light to hot loads. Both reloads and factory ammo. Doesn't matter, it just does. I don't Ben have to fire it. I can chamber a round, close the bolt, open it, and I'll have brass on the bolt face. I'm sure it has to do with slightly off chamber dimensions, but who cares as long as accuracy doesn't suffer (which it doesn't) . I just accept it as the 'personality' of the rifle and work around it.

 

[palma]

Carbon built up in the throat?

 

[rman1]

Carbon built up in the throat?

Nope. Scrubbed clean upon delivery. Flitz mirror clean. Its about the only time I do clean.

R.