O-Rings for Shimming Primer Pockets?

[Matthew323]

In the posts that I have read here at MM, there are 2 different types of o-rings mentioned for shimming the 209 primer pockets.

Buna-N, and Viton.

McMaster-Carr
Metric o-rings
6.5mm×4.5mm×1mm
O.D.×I.D.×Thickness

Buna-N
Black
#9262K611
Durometer 70A (medium)
-20°/+250° Fahrenheit
$4.91 Pkg/100
4.91 cents each

Viton Fluoroelastomer
Brown
#1185N26
Durometer 75A (medium)
-10°/+400° Fahrenheit
$9.04 Pkg/50
18.1 cents each

Which ones do YOU USE?
WHY did you choose them?
How do they work?
How many shots do they last for?

Thanks for your input.
Bruce

 

[BuckDoeHunter]

I use the black Buna-N.
That's what was recommended.
Work good, seal very well, I have had a few stick to the primer when the primer is removed but that is in a bolt action application not a break action.
Still to be determined on how long they last, I just started to use them in 3 smokeless bolt action muzzleloaders.

I haven't seen the brown ones, do they compress the same as the black ones?

 

[michiganmuzzy]

I use the Buna-n. I had not seen the Viton orings before. I bought a few hundred by mistake. I use them in an Accura 45. I put in a new one for each range trip and shoot 20-30 shots each trip. It could go longer but i just change it for the next trip. Im shooting bh209 85grV and 346grn lead bullet. I will buy some of those Vitons and give them a try just to compare. But the Buna rings are working fine for me and i like the lower price.

 

[Matthew323]

I use the black Buna-N.
That's what was recommended.
Work good, seal very well, I have had a few stick to the primer when the primer is removed but that is in a bolt action application not a break action.
Still to be determined on how long they last, I just started to use them in 3 smokeless bolt action muzzleloaders.

I haven't seen the brown ones, do they compress the same as the black ones?

The Durometer Shore A Hardness Scale is a measure of reference for flexible mold rubbers.

The brown Viton o-rings are just slightly harder than the black Buna-N o-rings.

 

[MSalyards]

I bought what ever was recommended from McMaster. No luck for me . Didn't work. I even got a new factory breech plug to start from scratch and mic'ed the primers and sorted them to a specific size. No go. My next experiment will be to try a Lehigh BP as I heard that helps. I still carry the stuck primer remover on my lanyard with my bullet starter

 

[Matthew323]

I just ordered the Lehigh Defense QRBP BH209 breech plug with vent liner, plus a pkg/4 additional vent liners this morning.

They are on their way to Utah to DOC White for the Optima V2 pistol.

 

[michiganmuzzy]

I bought what ever was recommended from McMaster. No luck for me . Didn't work. I even got a new factory breech plug to start from scratch and mic'ed the primers and sorted them to a specific size. No go. My next experiment will be to try a Lehigh BP as I heard that helps. I still carry the stuck primer remover on my lanyard with my bullet starter

Youre still getting lots of blowby? Even with the orings and longest primers?

 

[jsteurrys]

Viton. I used them for years in Knight DISC based guns with good results. I just started using them in my Remington 700 ML .45 conversion. They have addressed the constant wear of the Bolt Retention Screw. The "o"-rings are holding up well so far.

 

[jsteurrys]

I bought what ever was recommended from McMaster. No luck for me . Didn't work. I even got a new factory breech plug to start from scratch and mic'ed the primers and sorted them to a specific size. No go. My next experiment will be to try a Lehigh BP as I heard that helps. I still carry the stuck primer remover on my lanyard with my bullet starter

What gun is this in? You might need to put a shim(s) under the "o'-ring to get it to seal. I had to do this with a Knight DISC Original that was threaded 0.022" deeper than the DISC Elites. There is also a lot of variation in the bolts. There is 0.009" difference in the ones that I have.

 

[toytruck]

I would wait till you get your pistol Bruce. I tried the O-rings in both my Optima V2 rifle an pistol with W209 primers an they didn't work. The action would not close with the O-rings. You could use a shorter 209 primer to see if that helps, but again you might not need these rings in the primer pocket.

I do have the O-rings in the firing pin assembly which brought it flush with the face of the breech an that has worked so far. Just my opinion....

 

[snapbang]

I use the Buna-n. I had not seen the Viton orings before. I bought a few hundred by mistake.

want to sell 30-40???

 

[michiganmuzzy]

want to sell 30-40???

Sent u a PM

 

[michiganmuzzy]

I would wait till you get your pistol Bruce. I tried the O-rings in both my Optima V2 rifle an pistol with W209 primers an they didn't work. The action would not close with the O-rings. You could use a shorter 209 primer to see if that helps, but again you might not need these rings in the primer pocket.

I do have the O-rings in the firing pin assembly which brought it flush with the face of the breech an that has worked so far. Just my opinion....

I have to slam my Accura pretty good to latch it on a new oring

 

[MSalyards]

Yup , I'm not sure why they do not work. Seems a lot of folks have no problems. Mine stick 95% of the time. My loads are 77 w gr of BH, and a 300 gr Deep Curl in a crush rib sabot. Like I said, a new BP had the same affect and mic'ed out the same as the original. Also using the Win 209 primers.

Youre still getting lots of blowby? Even with the orings and longest primers?

 

[Matthew323]

I would wait till you get your pistol Bruce. I tried the O-rings in both my Optima V2 rifle an pistol with W209 primers an they didn't work. The action would not close with the O-rings. You could use a shorter 209 primer to see if that helps, but again you might not need these rings in the primer pocket.

I do have the O-rings in the firing pin assembly which brought it flush with the face of the breech an that has worked so far. Just my opinion....

Thanks, I will wait until I shoot the pistol.

 

[michiganmuzzy]

Yup , I'm not sure why they do not work. Seems a lot of folks have no problems. Mine stick 95% of the time. My loads are 77 w gr of BH, and a 300 gr Deep Curl in a crush rib sabot. Like I said, a new BP had the same affect and mic'ed out the same as the original. Also using the Win 209 primers.

Sent you a pm, too.

 

[Travis299]

CVA Accuras V2 & MR. We use this O-Ring. McMaster-Carr Pic of a squeaky clean fired primer (note NO O-Ring on the fired primer). We shoot 2 pellets of T7 & BH209. O-Ring lasts 10/20 shots BUT you get 100 for about $5. Make sure that the firing pin bushing is flush with the receiver face.

 

[snapbang]

Glad this got clarified. So the o ring goes on the primer. Needs to be removed and moved to the next primer. I was going to install that baby under the primer in the primer hole of the plug.

 

[Travis299]

Glad this got clarified. So the o ring goes on the primer. Needs to be removed and moved to the next primer. I was going to install that baby under the primer in the primer hole of the plug.

No, the runbber O-Ring is pushed into the primer pocket using a primer. When the primer is inserted and the rifle action is closed with a firm snap the O-Ring compresses somewhat and seals the primer in the pocket so that ALL of the hot gas goes through the flame channel & flame hole and ignites the powder charge. This prevents the blowback from exiting to the rear of the primer and fouling the firing pin assembly.

 

[michiganmuzzy]

Glad this got clarified. So the o ring goes on the primer. Needs to be removed and moved to the next primer. I was going to install that baby under the primer in the primer hole of the plug.

It does look like there is an oring on that primer. I think its just the lighting maybe. But no, the oring goes into the primer hole, then the primer goes into the primer hole. Oring usually will stay down there in the hole.