I have successfully rebuilt my NewVaq357 into a true 9mmPara using a Bowen cylinder black and a 3.25" section of Douglas Premium .355" barrel leftover from somebody's 9mm carbine project
. Initial shooting tests show it's a winner. Throats on the cylinder are .3555" via a chucking reamer, following along after a Manson finish reamer did the chambers smooth as a baby's hind end. Barrel is Taylor Throated.
First test out, total crap UMC 115gr ball ammo from Walmart dropped into 3" at 15 yards offhand without even trying, while just doing initial function testing.
Getting the barrel off was a stone-cold-female-doggie. I had read horror stories of bent/damaged frames, and ended up building a hilariously elaborate frame wrench out of hardwood, multiple wood clamps and half a tube of putty epoxy (using layers of cellophane each side to avoid glue on the frame/barrel). It worked.
The new barrel assembly is in four pieces:
* Core barrel is threaded 11/16th-24tpi for the Ruger frame at the rear, 9/16ths-18 at the muzzle. Barrel diameter along the main shaft is narrow - as in "looks like it came off a Glock" narrow.
* There's a thick stainless high-polish "shroud tube" around the core barrel (section of handlebar from a 1980 Honda 900!), not touching the core rifled barrel at all, that is under compression from...
* ...a "muzzle nut" of 9/16ths-18 that pulls the barrel forward, compressing the outer shroud against the frame.
* Surrounding the muzzle nut is a combination front sight base and gas trap used to trigger the gas-powered auto-shell-ejector system - a copper line that goes straight back into the frame to punch out empties as I shoot. This front base and gas trap holds to the muzzle nut by four set screws which ride in a channel carved into the muzzle nut, so that the base/trap piece can be spun for windage adjustments without reducing the barrel tension.
On assembly the barrel/cylinder gap can be finger-adjusted before it's all tightened down, just like a Dan Wesson. This was far, FAR easier to home-brew than a traditional "screwed in tight" Ruger barrel assembly.
Next up: I'm going to seriously improve the looks of the two-stage loading gate needed for gas-ejecting empties, and the big mod next is magazine feeding
. By the time I'm done, I'll be able to hold the cylinder's worth of rounds (possibly just five-up) plus have a short one-round magazine for holster carry. On my belt will be one foot long 9rd tube mags that can be swapped in at any time, injecting rounds into the frame at the left of the hammer from the shooter's view the moment an empty chamber passes in front of the mag. This means up to 14rd capacity without reloading if I have time to swap mags and prep.
Or put another way, the six to start combined with a pair of nines means doing a whole Steel Challenge stage with only two reloads instead of three, making it competitive head-to-head with GP100s or the like
. And the rulebook doesn't ban it - yet
Plus...SASS has been joking around about a "Steampunk class" for some time...wait'll they get a load of Maurice here...
The 9mm conversion was a prerequisite to magazine feeding. It's still going to be very hairy. I'm going to have to gently shave the left side of the pawl to allow enough clearance for the rounds to slip by it. I think it can still work but this would be a lot easier (not to mention cheaper!) had I started with a large-frame Ruger Blackhawk in 357/9mm convertible.