I'm always changing configurations with my various Crosman 22XX guns. Their modular design makes it easy to go from pistol to carbine to rifle and back in a few minutes. Combined with a few adapters, I've been able to try several interesting combinations. In the last blog post, I had thrown together a .20 caliber carbine and wanted to use a vertical fore grip from Magpul. Assembled, it felt pretty good, but there wasn't a spot for a front sling position. Granted, a single point rear sling worked just fine, but most of these projects come about from trying to solve a unique problem.
A bit of head scratching and I thought a QD front sling attachment could be incorporated into to a modified gas tube cap.
Rather than butcher the original cap,
Started from zero with a piece of 7/8" diameter 12L14.
Turned the end down to about .8085"
And threaded with a very uncommon 13/16 - 28 die to match the Crosman 22XX gas tube.
The camera angle is bad, but I used a thin parting blade to cut a relief at the end of the thread.
Since I'm using the Crosman mid-length 2250 gas tube, the cap will need an extension to bear against the end of the 12G CO2 cartridge. Might as well plan ahead for the three different Crosman gas tube lengths--2240, 2250, 2260.
A #3 drill is the correct diameter--
for a 1/4-28 tap.
More on this later.
Cut off the excess.
Cleaned up the face.
Drilled 3/8". This is where several small errors compounded and went slightly sideways. The tailstock was a bit out of alignment, the drill bit cut a bit oversize, I wasn't paying enough attention and this probably became a version 1 prototype.
Bored the undercut for the QD swivel.
Some cosmetic clean up.
A piece of sacrificial 1/4-28 in one end and a UTG 1-1/4" QD swivel kinda fits the other. A bit loose due to the oversized hole. Tried six or seven QD swivels and had mixed results. Half pulled right out, and half worked -- with a bit more wobble than I'd hoped, but they do hold securely. It's not exactly a disaster, but it will limit swapping and might require dedicating a sling.
Chucking that sacrificial 1/4-28 stud gave enough room to get a knurling tool in there.
Looks pretty good.
OK, back to making the rod.
Piece of 5/16" diameter was turned down and threaded 1/4-28.
A 1/2" carbide bur produced a concaved end.
Some clean up and polishing.
A bit longer than the Crosman cap.
Blackened with G96 paste.
Short set up with a Magpul RVG and sling.
And with the Strike Industries pistol brace.
Gonna work with this for now. If you have several push button QD swivels and guns, you probably know there isn't 100% guaranteed compatibility. Too many manufacturers, no hard standard.
I've always used a Magpul QD as the "standard" and done the machining to make that the best fit. I do wish that the airgun manufacturers would put a bit more thought into how to make their products better interface with some of the other gun "standards' out there. I think that means making the airguns accept off the shelf AR buffer tubes and stocks, bipods, Picatinny rails rather than dovetails... Those accessory purchases go further when they fit several platforms and it makes the end user's ability to tailor the gun that much easier. Or something like that.
For now, it's functional. So, maybe it's not a prototype after all. Now my options have options.
Thanks for checking in on me.
