Sooty mess

[Bowanna]

The 500 Federal 209MZ primers I ordered seem to have a considerable amount of blow back(black soot all over breech and plug)so I ordered the McMaster-Carr o-rings that I think michiganmuzzy was talking about in a thread a few months back.
I got 'em, now what do I do with them?

 

[ElDiablo]

Put one in the primer pocket of the plug.

 

[Bowanna]

Put one in the primer pocket of the plug.

Sorry ElD. Ok, if the Winchester 209(which aren't a problem) are.302 long and Federal 209mz's are .294 I'm to put an oring in the plug then the primer? I don't think the barrel will close but I'll try when I get home. Can't believe 8thousandths of an inch make a mess! We' ll see!

 

[ElDiablo]

Yep - the o-ring goes in the bottom of the primer pocket. Yes, .008” can make a huge difference in blowback.

 

[Bowanna]

Yep - the o-ring goes in the bottom of the primer pocket. Yes, .008” can make a huge difference in blowback.

Thanx man, I'll give it the ol college try when I get home and post ya!

 

[Bowanna]

Thanx man, I'll give it the ol college try when I get home and post ya!

Damn them things are tiny! My big ass hands and the 60somethin' eyes had a go of it and got it in. Put a problem primer in and, rather sharply, snap it closed. Tight but closed. By breaking this primer it won't show me anything, will it? Gotta have a charge in for blowback, Correct?

 

[MrTom]

By breaking this primer it won't show me anything, will it? Gotta have a charge in for blowback, Correct?

Try firing just the primer to be sure the gun locks enough to shoot it. Then load it up and shoot it. The primer only will not tell much. Loaded will tell if the o-ring has done its job.

 

[Bowanna]

Try firing just the primer to be sure the gun locks enough to shoot it. Then load it up and shoot it. The primer only will not tell much. Loaded will tell if the o-ring has done its job.

Thanx MrTom and everyone else who added. Forecast says rain this weekend(again) might be able to squeeze a few rounds in between showers. I'll keep y'all in the know.
Oh, how many shots is one o-ring good for?

 

[MrTom]

Depending on how hot the load is, maybe 20-30. Maybe less if you're really cooking.

 

[Bowanna]

Depending on how hot the load is, maybe 20-30. Maybe less if you're really cooking.

85 to 95gbv, still workin' on finding the load they like.

 

[ElDiablo]

I’ve never worn one out. I just replace them every time I clean the rifle. They’re 5 cents a piece. Cheap!

 

[MrTom]

I’ve never worn one out. I just replace them every time I clean the rifle. They’re 5 cents a piece. Cheap!

I'm in the same camp as ElDiablo. When I ordered mine, I got three packages. A new one goes in when I finish cleaning the gun. I also put a spent primer in on top of the new oring. When I shoot the gun the next time, I don't have to close the gun with much force. Sometimes a guy has to really snap the gun closed if a new oring has gone in just ahead of shooting.

 

[Jitterbug]

I’m an O-ring user, as well.

My old man would’ve considered them to be “Mickey-Mouse.”

If the O-ring works for you… there’s also another (more permanent) option you might like:

Shims for 209 Breech Plug Primer Pocket

Not advocating one technique over the other… just another option!

I do think the O-ring gives more flexibility (both literally and figuratively). If you have a primer that’s a couple thousandths short, or a couple thousandths long, the elasticity of the O-ring might well accommodate for that. The “washers for primer pocket shims” pretty much lock you in, on a certain shim thickness.

Lots of rabbit holes to go down… what an incredible hobby!