doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Safety Issue: Defective Snap Caps Slide Down Bore

Daryl-

My initial comments on this thread are as follows, and you will note in paragraph 2 that the snap caps are accurately described:


"Last Fall, after cleaning my JP Sauer 20 gauge shotgun, I inserted 2 plastic Pachmayr snap caps in the shotgun. Last week I removed the gun from its case for a hunt. Upon opening the action, there was no visible snap cap in the right barrel. Fortunately the snap cap in the left barrel was still visible although it too had begun to slide down the barrel. I was able to get both snap caps out of the barrels. The plastic rim on each had disintegrated over the past year, allowing both the caps to slide down the barrels, obstructing the bores.

The snap caps are blue and marked Pachmayr, CAL.20 MADE IN ITALY."

I have no idea as to how to paste photos to this website. Most websites have a paper clip icon for attaching photos. However, I attached photos to Shotgunforums.com and if you can open the link, it is:
http://www.shotgunforums.com/forums/shotgun-accessories/3329-snap-cap-useage-4.html

Anyway, it is evident that despite being a poorly fabricated product, it appears from comments on this thread and my own subsequent research with my three 20 gauge shotguns, that these snap caps, although not visible when the chamber is opened, are unlikely to slide down the bore far enough to allow a shell to be chambered. Let's hope that this is the case for all that use this product.

I would add that Amazon which sells this product currently has 6 reviews- one 5 stars for the brass rimmed snap caps offered in pistol and rifle calibers and five 1 star ratings for the plastic rimmed shotgun snap caps:

https://www.amazon.com/Pachmayr-Snap-Dum...iews-filter-bar

I looked at the photos of these defevtive snap caps in your link, and they are clearly marked "Cal. 20 Made In Italy" just as you said.

So we are down to needing the measurements that Daryl asked for in order to determine just what is going on to permit these snap caps to fall well into the chambers of three different 20 gauge guns. I'd be most interested in the largest diameter of these snap caps, and the diameter of them at the end.

My first thought was the possibility that this was a gun you had never fired, and that it might actually be a 16 gauge. Being a J.P. Sauer made that possibility even more likely because of the popularity of the 16 gauge in Germany. And I have bought several guns that turned out to be a different gauge than advertised. When I bought my very first Syracuse Lefever, I got it from a guy who inherited it and knew nothing about it except that he didn't want it in his house where his grandkids might find it. It was so light and trim that I was sure it was a 16 gauge. When I got it home, I dropped a pair of plastic 16 ga. snap caps into it to drop the hammers, and they fell into the chambers. I had gotten very lucky on my first Lefever purchase by getting a very scarce small frame 12 gauge gun.

The fact that you tried these snap caps in two other 20 gauge guns kinda blows that theory out of the water. But the different depths that your caps went into these different chambers just goes to show the variability of chamber and bore dimensions that we deal with. Another possibility is that there was a manufacturing screw up, and some 28 gauge snap caps somehow got misprinted with the "Cal. 20 Made In Italy" marking. I've personally seen a number of such screw-ups made by human error during the changeover process in manufacturing. Again, I would beg, borrow, or buy a micrometer or digital caliper to get those measurements.

Keith

My hunting partner likely has a micrometer so I'll get take measurements when I see him in a week or so. Meanwhile I just took rough measurements with a ruler, results below:

Both defective 20 gauge Snap caps:

21/32" Front
22/32" Rear (area where rim dissolved)

Remington live round, 20 Gauge:

22/32" front (crimped end)
25/32" rear (includes rim on metal base)

You mention Lefever. I recall my Dad telling me a story in the 1950s. He and my Uncle were hunting in NJ and they came across a bloody scene in the woods. There were two shotguns on the ground, one a perfectly fine Lefever, the other a shotgun with an exploded barrel. My Dad and uncle were able to track down the owner of the Lefever and return the shotgun. (The guns were left in the woods because the hunter had to assist his injured companion out of the woods.) Anyway, that story has made me sensitive to obstructions in shotgun bores. It never would have occurred to me to attempt to insert a live round in the obstructed bores to see if the live round would chamber; rather I removed the obstructions in the JP Sauer barrels and believed it best to share my experience with fellow hunters.

This was not a mislabeling screw up- as the 20 gauge Pachmayr snap caps seated properly in the barrels when they were new while 28 gauge snap caps will not properly seat in a 20 gauge and thus immediately slide down the barrels. The Pachmayr plastic snap caps are merely a poorly designed product, not suitable for use as advertised. My sense is that the chemicals in the gun cleaner had an adverse effect on the plastic rims.

Ok, my original take was that the snap cap bodies went into the bore. They did not, I guess, and they were stopped by the forcing cone before getting into the bore.

Also, I think you will find that the plastic snap caps are not as long as the chamber boring. I'd "guess" the plastic snap caps are 2.1" , or there abouts, long, so that if the rim was removed they would naturally slide down the chamber .65" before hitting the beginning of the forcing cone, which is 2 3/4" long in all probability. One might "guess" that the snap cap might then go into the forcing cone a tenth of an inch before being stopped by the taper of the forcing cone. When the snap cap is stopped, in this scenario, it will have moved .65" plus .10" or .75" from the face of the breech. If the snap cap is shorter or the forcing cone is longer or altered, then that distance would be greater.

In this event, a loaded 2 3/4" shell could not be inserted and fired with the broken snap caps stuck in the forcing cones. A lot of aggravation , but no danger of the snap cap blockage of an exploding shell.

Thanks for your technical insight Daryl. The plastic rimmed 20 gauge Pachmayr snap caps are about 2� long, a live Winchester Super X 20 gauge round is roughly 2 9/32� long. Sorry for the confusion caused by my misreporting this issue, as I used to believe the forcing cone section as being part of the bore. I now know better !

And why leave snap caps in the gun anyway??

It�s my understanding that snap caps have at least 2 purposes; dry firing firearms and relieving tension on the firing pin spring when the firearm is stored. I use the snap caps after cleaning and prior to storing my shotgun. If I opened the action on my shotgun to remove the snap caps, I would be re-cocking the triggers. Thus I leave the snap caps in the shotgun after I pull both triggers. Perhaps some models of shotguns may be stored for lengthy periods of time without degradation of the firing pin spring. However some of my shotguns are older than me so I use snap caps prior to storage. I will be transitioning to A-zoom aluminum snap caps as a result of this incident.

A representative of Lyman Products contacted me re: this snap cap issue. I provided him with details regarding the degradation of the rims on the plastic snap caps, including photos. Apparently Lyman no longer distributes the blue plastic snap caps from Italy. He was kind enough to send me four 20 gauge A-Zoom (metal) snap caps.

Yeah mate, I use the A-Zoom metal snap caps. They are just slightly over crimped shell length. I believe them to be a good product.

Place snap caps in chamber, snap, snap, hammers down.
Remove fore end.
Open gun
Remove snap caps
Close gun
Replace fore end
Store in gun safe
Nothing in chambers or barrels, with spring tension relieved.
O.M