I have two of the adapters. When I purchased my Contender barrels from a guy in Alaska I got a .375 JDJ with a full length adapter for 22LR that had a tube all the way to the end of the barrel using a rubber O-Ring to center it for small game, maybe survival I guess and on the 222 Rem Mag barrel is has just the cartridge length adapter for 22lr. I have been thinking about having it re-chambered for 22 WMR if I can find someone to do that.
The tube for the .375JDJ shoots good but I have to hold under the target about 4 inches if I remember correctly. I marked the adapter with white paint dot so I would always insert the same when I shot it. I haven't seen any more of these since I got mine about 10 years back. They may have come from the company in Alaska. I think the company was MCA Sports, Chamber Adapters- Thinking about getting one for my Contender 45-70 to 22WMR.
Here is the link to their site- MCA Sports Chamber Adapters

Mike

Last edited by Hawkeye; 09/03/2020 2:50 PM.
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