[randy//]

I have been reloading for twenty years and have never ran into the problem I am seeing with the 7MM Mag. I am trying to load for. I am getting signs of pressure on the primer ,this is a raised rime/lip around the firing pin creator. I get this result even when using minimum loads with large rifle primers. I have trimmed cases, bumped shoulders back, used new brass, different brands of brass. In a nutshell, no matter what i do the results are the same. The only thing I can allow this to be is a problem with the reaming of chamber. I feel this is probably a tight chamber or throat. An feed back on this problem would be greatly appreciated.

[30Cal]

Could be softer primer cups, an oversized firing pin hole or overpressure.

A chronograph would quickly tell you whether you've got a real pressure situation.

[Cypress]

I have always found that primers are a poor sign of pressure. Mostly due to the fact that some are softer or thinner than others. I have loaded for a couple of guns that have showed the signs that you are speaking of. I believe that it was caused by the bolt design. The hole around the firing pin was larger than normal and allowed the softer/thinner primers to flow more easily. I checked the rounds with a chronograph and everything was in normal ranges. I proceeded with load testing with no ill effects. That being said, this was my experience and I think you should double check everything. Better safe than sorry.

[Cypress]

OK, what 30Cal said. That was easier!!

[rcmodel]

Unless the primers are flattened all the way to the edge of the primer pocket, and you are getting loose primer pockets after the first loading, the raised lip around the dent is not a pressure sign.

More then likely it is caused by an oversize / ill-fitting firing pin hole & firing pin tip.

Have you tried a different brand of primer?
Have you tried factory loads?

rcmodel

[Shoney]

What brand and strength of primer did you use in this load?

What brand and strength of primer did you use in the old loads?

[mkl]

Take a micrometer to the range with you. Measure the case head diameter (at the same point) before and after firing.

If you are getting any increase in diameter, the load is way too hot.

This is about the only "pressure indicator" sign you have left after primer inspection without a chronograph.

Actually, if there is something wrong with the chamber, a chronograph might not be a valid indicator (very short duration high pressure spike).

[SlamFire1]

I am seeing with the 7MM Mag. I am trying to load for. I am getting signs of pressure on the primer ,this is a raised rime/lip around the firing pin creator.

This a new M700? At my gun club I met a graybeard. He had a new M700 and the primers crated with loads that were not near max. He claimed to have called Remington and they told him that the firing pin hole size had been changed to allow primer flow around the firing pin. I suspect the hole is larger, I forgot. My theory is that primer flow into the firing pin hole would provide a better gas seal.

Reading pressure signs from primers is guess work. It is my considered opinion, that the only reliable signs of pressure are blown primers, pierced primers, and sticky bolt lift. These are gross indications and when you get them, you long ago exceeded safe pressures. Of course, if your pockets open up in less than five loads, you know that the pressures are high.

Ken Waters uses case head expansion, I tried that, and did not find a correlation.

I do use a chronograph to develop loads, and if my loads exceed factory with same bullet weight, or exceed published values, then I believe I am near or have exceeded a maximum load. There is no such thing as a free lunch, if your bullets are going fast, the pressures are high.

[mkl]

I hate to be argumentative, but hey:

Ken Waters uses case head expansion, I tried that, and did not find a correlation.

The correlation is that brass case heads begin to expand at pressures above 65-70 psi. You can't correlate CPU or PSI to head expansion, but you can correlate it to "this thing is about to blow up my case and my rifle." Remember this thread is about 7mm mag pressures.

Re my comment on a pressure spike with a really out of spec chamber:

IThere is no such thing as a free lunch, if your bullets are going fast, the pressures are high.

Agree with bullets fast equals high pressure generally. BUT a case full of Bullseye would not give a fast reading on the chronograph, but would show high pressure signs. Hence, my comment on a short duration very high pressure spike. A small obstruction in the leades would give high pressure without high velocity on a chrono.

[mswestfall]

randy//,

What is the make and model of the gun?

[Ridgerunner665]

Have the headspace checked.

[randy//]

Thanks to everyone for all your responses. Sorry for not including all the pertinent information on my rifle. The rifle is a Remington Model 700, CDL 7MM Magnum. I have used every primer ( different brands, types-Magnums,Large Rifle) with the same results. I do use my chronograph, with velocities running anywhere from 2850 to 3098 FPS depending on loads used. I have loaded 140 through 175 grain bullets. I have also used Winchester, Remington, Federal and as of yesterday Hornady brass. With the Hornady brass, there were better results. The over sized firing pin hole theory sounds like a likely reason for what I am seeing. There have been no Flattened or pierced primers and all loads used have been in accordance with my loading manuals. So maybe I do not have the problem I thought I was having. Thanks to everyone again. Randy//