Pressure Sign at this Charge Weight?

[kenmack]

I'm doing OCW for 7mm-08.
Federal once fired in same rifle
Neck sized Lee Collet
140gn Nosler BT
Federal Primer
Varget
Seated to magazine length 2.810"
Mildly cool temp.

I start to see brass smooge marks on the case head starting at 41.2 gn with a very light mark on one of three cases. Same thing up to 42.0 gn. The marks are a little more prominent at the higher charges and will show on two or three cases of those charge weights. There is no cratering of primers. The primers aren't appreciably flattened where I can say "yep, definately flattened". The head diameter is unchanged. Bolt opening is not difficult but seems somewhat stiff but I can't say that it isn't because I'm paying attention to it now that I reload. I got a chrono which showed less than 2650fps for the 41.9 I shot today. Factory Federal 140gn BT clocked 2725fps with 20" barrel.

I've never seen so much brass on my bolt face and just have to wonder if I might be doing something that would cause high pressures with low velocity. If I had less brass on the bolt face and 100 to 150 more fps, I'd call it good. I'm just wondering if something is wrong.

 

[Boltfluter]

Re: Pressure Sign at this Charge Weight?

Does the bolt close hard upon chambering.? Were the cases fired in another rifle before you got them?

Regards, Paul

 

[kenmack]

Re: Pressure Sign at this Charge Weight?

Fired in this rifle and no trouble closing.

 

[Deadshot2]

Re: Pressure Sign at this Charge Weight?

Some brass is different than other brass. I don't pay attention to brass on the bolt face as much as I do Bolt Opening. Even primer flattening is a poor indicator as some will flatten to the point where it's hard to see the separation between them and the case, even though the load is well below max.

Even ejector marks on my Remington vary from case to case, even with the same loads that produce single digit SD/ES numbers when chronographed

Case head growth and bolt opening difficulty are pretty much absolutes.