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Master_Mechanic
07-24-2014, 10:40 AM
I have a couple smith and wesson 686's, the other week i was shooting some 357 reloads when i had a primer get pierced and come out of the primer pocket. I figured that was an overcharge due to the fact that only one did it and they were reloads i got from another shooter. Last night at the range i took the same gun out with some 38 special loads 160gr round nose lymann with my usual load of 3.2gr bullseye and was having primers back out of the primer pockets slightly, but enought to tie up the gun. I tried a few rounds from another box, same thing. I then tried those loads in my shorter barelled 686 and my fathers R8 with no issues. Up until I pierced that primer i havent had any issues with the gun. Any suggestions what to look for?

fourarmed
07-24-2014, 03:35 PM
Sounds like a headspace problem. Does that revolver have a lot of end shake?

Master_Mechanic
07-24-2014, 03:36 PM
endshake? not familliar with that term, could you explain? thanks

RED333
07-24-2014, 03:53 PM
End shake is the cylinder moving back and forth in the (O what is the word) pin it rotates on.

Master_Mechanic
07-24-2014, 03:57 PM
if i roll the cylinder out theres a bit there, but once the cylinder is in the frame and the gun is cocked there is very minimal play there.

44man
07-24-2014, 04:16 PM
Check the firing pin bushing, a pierced prime might have raised a burr.

ReloaderFred
07-24-2014, 06:52 PM
When the priming compound explodes, it drives the primer out of the primer pocket, stopping against the back plate of the revolver. The explosion then starts the powder burning and the pressure from the slower burn of the powder drives the case back and reseats the primer. This is a choreographed occurrence, and if the pressure isn't enough to drive the case back hard enough, then the primer remains at least partially out of the primer pocket.

If your powder charge isn't producing enough pressure to reseat the primer, then the protruding primer will lock up the cylinder. Some revolvers are more forgiving than others, so I'd try a little stouter charge of Bullseye and see if that cures the problem in this revolver.

Hope this helps.

Fred

Scharfschuetze
07-24-2014, 07:26 PM
Fred probably has your problem identified.

When shooting wax bullets (at butcher paper with a movie playing on it-pre FATS technology) at the police academy, the firearms instructor told us that he had to drill the flash holes out so that the primers did not back out and tie up our revolvers. The goal was to reduce the pressure in the primer pocket to less than the chamber pressure of the load.

I've since used that trick many times over with wax and squib loads for the kids when they were growing up.

The pierced primer? Maybe a faulty or too thin primer cup?

Le Loup Solitaire
07-24-2014, 09:57 PM
It is a long standing practice to drill out/enlarge the flash holes on cases that are to be used with just the primer for propulsion and wax bullets. The bullets are a wadcutter shape achieved b pressing the mouth of the case down over a sheet of wax usually about 1/4 " thick prior to priming. A cardboard box with a target front is sufficient for trapping the wax projectile....which can be remelted and reused. The cases should be somehow marked and kept segregated and not used for regular reloading. LLS

Master_Mechanic
07-24-2014, 10:24 PM
I have shot this load many times out of this revolver with no issues then all of a sudden this started happening, I understand the way it works but it seems odd to have it show up with a tested load.
When the priming compound explodes, it drives the primer out of the primer pocket, stopping against the back plate of the revolver. The explosion then starts the powder burning and the pressure from the slower burn of the powder drives the case back and reseats the primer. This is a choreographed occurrence, and if the pressure isn't enough to drive the case back hard enough, then the primer remains at least partially out of the primer pocket.

If your powder charge isn't producing enough pressure to reseat the primer, then the protruding primer will lock up the cylinder. Some revolvers are more forgiving than others, so I'd try a little stouter charge of Bullseye and see if that cures the problem in this revolver.

Hope this helps.

Fred

Dale53
07-25-2014, 12:08 PM
There were some early 686's that had this issue. Apparently, it was caused by the firing pin bushing backing up when fired. Open the cylinder and see if the firing pin bushing is flush with the revolver back plate. If it is slightly "depressed" it can allow the primers to back out. Smith will be able to solve this (or a local pistolsmith). If you find this condition, have the serial number of the revolver on hand and call Smith &Wesson and discuss this with them. The problematic revolvers were recalled. If yours are one of these, Smith may send you a mailing slip to have them repair at no cost.

Let us know what happens, please...

FWIW
Dale53

Master_Mechanic
07-25-2014, 12:43 PM
There were some early 686's that had this issue. Apparently, it was caused by the firing pin bushing backing up when fired. Open the cylinder and see if the firing pin bushing is flush with the revolver back plate. If it is slightly "depressed" it can allow the primers to back out. Smith will be able to solve this (or a local pistolsmith). If you find this condition, have the serial number of the revolver on hand and call Smith &Wesson and discuss this with them. The problematic revolvers were recalled. If yours are one of these, Smith may send you a mailing slip to have them repair at no cost.

Let us know what happens, please...

FWIW
Dale53

Only thing that makes me nervous about going that route, or even if it does need a gunsmith is being in canada we have to jump through hoops to get it sent anywhere let alone back to the states. Im not sure of any good gunsmiths around that can do the job either

runfiverun
07-26-2014, 12:17 PM
check that firing pin bushing.
they are there to wear out and be replaced.

i remember seeing a colt revolver going full auto when i was a kid.
it was brought into parkers shop, the owner was telling him about it and he test fired it in the back of the shop
shur nuff.... click,click,click,click..... boom,boom,boom,boom,boom. [dang near ruined the test barrel he had back there]
the bushing was [waaay] worn out and the primers were allowing gas to escape, re-cocking the hammer each time.

44man
07-26-2014, 01:16 PM
Yep, check the bushing to make sure it is flush with the recoil plate. Had a gun here a little while back. I had to make a new bushing.
Those old Colts had a sharp pin on a few that would puncture a primer. But did you know hammer bounce is common on all guns.

seaboltm
07-26-2014, 02:23 PM
How many times have the cases been reloaded? Could the primer pockets be loose?

Master_Mechanic
07-26-2014, 02:24 PM
How many times have the cases been reloaded? Could the primer pockets be loose?

Could be loose, been reloaded an unknown amount of times, I doubt that's it due to the fact it does it every. Time the trigger is pulled.

fourarmed
07-26-2014, 04:35 PM
If it turns out not to be the FP bushing, check the barrel/cylinder gap when the gun is cocked. If it is small to non-existent, then you probably have end play in the cylinder. Grasp the cylinder with the action uncocked, and see if there is excessive fore and aft movement. If so, it can be repaired with shims, although there is a better and more permanent fix.

Outpost75
07-26-2014, 07:53 PM
Firing pin bushing coming loose and/or end shake, very common problem with S&Ws.

Back in the day was common failure mode for light alloy frame Colts if shot with +P

Frank46
07-26-2014, 11:41 PM
Don't know much about the 686 series but if your getting pierced primers while checking the bushing also check the firing pin. The hot escaping gas can pit the tip of the firing pin and also lead to more pierced primers. Frank

Master_Mechanic
07-27-2014, 02:41 PM
Yep, check the bushing to make sure it is flush with the recoil plate. Had a gun here a little while back. I had to make a new bushing.
Those old Colts had a sharp pin on a few that would puncture a primer. But did you know hammer bounce is common on all guns. Firing pin bushing needs to be replaced, just took a look at it and it is pushed in at the top. Thanks for all the help. And btw this is a 686 no dash, should be warranty.

Artful
07-27-2014, 08:00 PM
Only thing that makes me nervous about going that route, or even if it does need a gunsmith is being in canada we have to jump through hoops to get it sent anywhere let alone back to the states. Im not sure of any good gunsmiths around that can do the job either
It doesn't have to come to the USA - Smith and Wesson have factory warranty stations around the globe

http://www.smith-wesson.com/webapp/wcs/stores/servlet/Category4_750001_750051_757819_-1_757814_757812_image
CANADA MURRAY CHARLTON ENTERPRISES LTD
BOX 42
BRENTWOOD BAY
B.C., CANADA V8M 1R3
Phone: 778-426-3884
Fax: 778-426-3886

FergusonTO35
07-27-2014, 09:53 PM
I would try different brass and primers. I once had a box of Winchester SP primers that must have been undersized. You could practically seat them with finger pressure. I tried them with a light 9mm load and one of the primers popped out and jammed the action.