I had about 6 built over the past 3 years using the reamer specs pictured below. Reamer is designed with sufficient free-bore to seat long 105 Ber VLD's long enough to minimize bullet intrusion in the boiler room. Reamer was also designed for tight NK requiring only that the neck need to be cleaned up with an outside NK turner.
I have put Dasher barrels on both a Bat repeater, and Barnard S actions. Barrel contours from HV to #3 Kreiger.
If building on a repeater action, it is necessary to block the back end of the magazine box and shorten the carrier plate ...so bullets feed properly.
When loaded with 32.4 gr Varget, from a 26" barrel, mine chrony with 2970 fps at muzzle. I have not taken them past 33 gr Var.
Reamer Specs
Brass prep ... left-parent 6BR / necked up to .264 / necked back down to 6mm with Dasher die to form false shoulder / 6 Dasher
Magazine Conversion
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