Sounds like a Striker barrel switch to me. I'm not sure but a 22BR go/no go set might work for the 6 and 7BRs. I recently go a 243 go guage that will work for 7-08 and 308 since they all have the same index point on the shoulders. Just a thought.
Lynn Shultz
IHMSA #15692 since 1980
Past Match Director Logan Handgun Association
Current VP Logan Handgun Association
NRA Member
United States Air Force Veteran
Retired USAF Civil Servant (47 years)
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