Diamondback Six
CGN frequent flyer
Bumping this old thread to resolve the mystery of the BCM vs Diemaco 0.3"/7.62mm length difference...
I can't find the reference pics one of our members sent me, but I did find some notes I think I took from them and I just took fresh measurements off the BCM, so I'd appreciate help filling in the blanks. Measurements here are in inches.
lug R shelf to sleeve 2-5/16 - BCM ? (not sure where I had meant by "rear shelf of bayonet lug")
FSP front to sleeve R ? - BCM 3.25
rear skinny section 1.25 - BCM 1.3125 - D .0625
middle fat section 9/16 [I distrust this number] plus taper - BCM 1.0 plus taper
front skinny section ? to taper - BCM 1.25 to taper
sleeve oal 3-5/8 - BCM 3-5/8 - D 0
Right now, it looks like BCM just turned down the front 3-5/8" of a 16" barrel rather than any cute "stretch the sleeve" tricks. If I had the shoulder turned back another 0.3" and the muzzle threads similarly extended toward the FSP, are there any potential complications from having the muzzle 1/3" further into the FH?
I suspect your Eickhorn is either a little longer than our M9 or OKC-3S, or has a larger-diameter barrel ring; the OKC-3S measures 4-5/8" from ring rear to front of lug socket and bottoms out against the fat middle of the sleeve 5/8" ahead of locking position on the lug (0.325" if adjusted for Diemaco shorter length) with a 7/8" inside-diameter ring and a sleeve maximum outside-diameter of 1.0". Even adjusting for length, unless the Eickhorn's grip is at least a quarter-inch longer than the Ontarios.
I can't find the reference pics one of our members sent me, but I did find some notes I think I took from them and I just took fresh measurements off the BCM, so I'd appreciate help filling in the blanks. Measurements here are in inches.
lug R shelf to sleeve 2-5/16 - BCM ? (not sure where I had meant by "rear shelf of bayonet lug")
FSP front to sleeve R ? - BCM 3.25
rear skinny section 1.25 - BCM 1.3125 - D .0625
middle fat section 9/16 [I distrust this number] plus taper - BCM 1.0 plus taper
front skinny section ? to taper - BCM 1.25 to taper
sleeve oal 3-5/8 - BCM 3-5/8 - D 0
Right now, it looks like BCM just turned down the front 3-5/8" of a 16" barrel rather than any cute "stretch the sleeve" tricks. If I had the shoulder turned back another 0.3" and the muzzle threads similarly extended toward the FSP, are there any potential complications from having the muzzle 1/3" further into the FH?
I suspect your Eickhorn is either a little longer than our M9 or OKC-3S, or has a larger-diameter barrel ring; the OKC-3S measures 4-5/8" from ring rear to front of lug socket and bottoms out against the fat middle of the sleeve 5/8" ahead of locking position on the lug (0.325" if adjusted for Diemaco shorter length) with a 7/8" inside-diameter ring and a sleeve maximum outside-diameter of 1.0". Even adjusting for length, unless the Eickhorn's grip is at least a quarter-inch longer than the Ontarios.
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