Rem 700 Stainless - Primer Cratering

[Picher]

I have a relatively new Rem 700 Stainless LV, .223 Rem. One problem I can't seem to correct is that it craters primers, with all loads. It's not a pressure problem, since I'm using relatively mild loads.

Other than the crater at the firing pin hole, the rest of the primer is not flattened, but perfectly normal.

Accuracy: Grouping is only about 1.25" at 100 yards, but same loads in another rifle does 1/2".

What I've done:

Taken the bolt apart and cleaned/lubed the firing pin.
Checked pin protrusion... .050" It's the same as other 700s.
Replaced the firing pin spring.
Replaced the bolt shroud with a non-locking one.
Re-checked the sizing die setting and have minimal case fit to chamber.
Varied bullet seating depth from zero to 1/10" to lands with no results.

Any suggestions?

Picher

 

[Dixie Gunsmithing]

Did you check for the correct shape of the firing pin nose?

 

[tangolima]

Is the firing pin hole in the bolt face over sized?

-TL

 

[Picher]

The firing pin nose is correct and it fits the bolt face the same as other Remington 700s I have.

 

[Mobuck]

The rifles I've seen with these symptoms had enlarged FP holes in the bolt face-one from extensive dry firing and the other possibly a factory error. The other cause could possibly be a weak FP spring which is allowing the FP to be pushed back into the bolt during firing.

 

[Slamfire]

I met a guy at the range whose M700 was doing the same thing. He called Remington and was told that Remington had modified the bolt face so that primers did flow into the firing pin hole. I think it was to improve gas sealing.

Call Remington and see if it is so. If Remington drilled an extra large firing pin hole, I don't see a fix other than a new bolt.

 

[tangolima]

The firing pin hole should have a good fit over the pin; 1 or 2 thousandth over. Over sized hole is a problem, not a feature.

It can be fixed by retipping the pin. Not difficult to do if you have a lathe for center drilling. Any competent Smith can do it for less than replacing the bolt body.

BTW, how does the rifle headspace?

-TL

 

[hoghunting]

A buddy had the same problem with his 700 and replaced the firing pin with an oversized pin, it corrected the problem.

http://www.midwayusa.com/product/12...ized-accelerated-firing-pin-kit-remington-700

 

[243winxb]

Remington 700 bolt face.

Normal for some Rem 700s.

[/URL][/IMG]Not a true pressure sign. Reload left, factory on the right. Reply from Remington to me. "The cratering you are experiencing is from a design* in the bolt face, it does not effect any thing in a negative way it is a worry to some because it makes it difficult to read your primers for reloaders. With this said Remington will replace your bolt, follow the instuctions on the web-site for sending your whole gun to us for repair" Read this online " normal on guns manufactured between 2008 and 2010."

[/URL][/IMG] Click photos for larger view. Or have a smith "bush" the firing pin hole.

 

[tangolima]

It could be normal to Remington, but not so to any one who knows how things work. Another Remington SNAFU.

-TL

 

[Picher]

Thanks, folks. I appreciate the advice.

I was concerned that the firing pin spring wasn't providing consistent ignition. I took the bolt and firing pin assembly apart, cleaned and lubed the pin and inside the bolt, and am now getting better groups (7/16"). The cratering remains, but diminished somewhat.

Picher

 

[scoobydoo6906]

Primer cratering is no good period. Remington is blowing smoke up you know where by saying it's normal. Cratered primers are on the edge of rupturing even without pressure signs. Something is wrong, and it's likely an oversize firing pin hole. Remington's QC has been shaky at best as of late, and if they are indeed telling people that a cratered primer is ok then they are dead to me.

 

[tobnpr]

Well known problem with 700's having oversize FP holes...
Found this out years ago with our first VTR in .223.
Despite lightish loads, we were getting cratering. New to handloading at that time, it was quite a source of headscratching and confusion until this was pointed out to me.

 

[Picher]

I ordered an oversized firing pin and extra power mainspring from Midway and it's in the mail.

Thanks for the help guys!

P.S.: I decided to not return the rifle to Remington for repairs. I should be able to fit the new pin without much trouble. (The bolt shroud doesn't have a j-lock.)

 

[CowTowner]

Picher, can you post a picture of the fixed bolt? I'd like to see the difference once you have the new firing pin fitted.

 

[UncleGrumpy]

With cratering like that, aren't you having trouble sliding it into the reloading press shell holder?

When did Remington start oversizing the hole?