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.
