I recently bought an auction lot out of a Denver area online auction that had 3 AR barrels that I am trying to identify. Two of the barrels are new and the third only shows signs of being installed on a receiver. A chamber cast shows that it is probably based off of the x39 family. Unfortunately the 35 year old cerosafe crumbled before we could get any other measurements. A new batch is on the way. Does anyone know anything about these barrels whose only markings are 6mm A.F. (1 in 12) N.R.A.
6mm A.F. what is it?
- Thread starter Thaine
- Start date
Eric_Mayer
Member
Could the barrel marking be "AR", not AF? If so, maybe it is the 6mm AR cartridge. Who is the manufacturer of the barrel?
Eric,
Thanks, but they are clearly A.F. Maker is unknown and "6mm A.F. (1 in 12) N.R.A." is the only marking. Three barrels all done in a production style mark. Note there is an R in the NRA and it is clear the F is correct and not an R. I got some cerosafe in and will be casting the chamber. The shoulder looks to be perhaps an Ackley style so it is possible it is a reverse engineered version of the 6mm Tubo AR. The developer of those cartridges, like Alexander and the Grendel considered the specs proprietary.
Thanks, but they are clearly A.F. Maker is unknown and "6mm A.F. (1 in 12) N.R.A." is the only marking. Three barrels all done in a production style mark. Note there is an R in the NRA and it is clear the F is correct and not an R. I got some cerosafe in and will be casting the chamber. The shoulder looks to be perhaps an Ackley style so it is possible it is a reverse engineered version of the 6mm Tubo AR. The developer of those cartridges, like Alexander and the Grendel considered the specs proprietary.
Eric_Mayer
Member
Interested to see what it turns out to be.