F22_RaptoR
CGN Ultra frequent flyer
- Location
- Edmonton, Alberta
Some of you guys may remember that I've been working on a custom made USC/UMP stock block. Well after getting some range time on Saturday, I can say that its a complete success! 
I wanted an Ar15 stock adapter, since the adjustable LOP stock makes MUCH more sense to me than a folding stock, and I already had a Magpul CTR laying around ready to be used for something, so why not?
Its made of 6061-T6 Aluminum, and unfortunately I had to paint it black, since the anodizing place I emailed never returned my emails . In any case, it looks just as good.
The sling plate at the back is recessed into the block, and allows the use of an HK-clip single point sling, fully ambidextrous, and doesn't interfere with your hand at all. Awesome setup IMHO. Rather than messing with the metric threads for the screws, I ripped apart the OLD USC stock, and took the steel threaded insert out, and press fit, epoxied, and pinned the insert in. Its ridged for the plastic, so i made the hole EVER SO SLIGHTLY smaller, so I had to use a vice to press fit it in. Its ROCK SOLID! aint going anywhere!
I got a half-barrel blank that my friend got for some handgun barrels, and had his machinist copy my USC barrel except for the length, which is the normal 8" UMP barrel length (or 7.87). All I need is to bring it back and get it threaded (I wanted to test the crown before I got it threaded and completed). Going to get it threaded for the 16x1mm RH thread same as my Mark23, since I already have a flash suppressor for it, and a fake suppressor for pics. Groups pretty damn well, my buddy was making some 5-shot-touching groups at 25 yards, and I was killing a piece of 2x4 hanging on a string at 50 yards! SO much fun to shoot!
You can see the sling point on this one.
Closeup of the stock block. Note that since it was painted, I had to scrape some paint off since the tolerances are VERY tight on it.
Put a hundred rounds through it with no problems at all. I only had 1 5/10 round mag with the spacers on it, so it was kinda hard to keep loading it up after 5 shots. Now Im waiting on some 5/25 UMP mags!
ETA
Some info on the stock block, and the stock. There is just enough room for the AR15 stock to go into the rear of the USC receiver and have some good meat on it. There is about 1/8th of an inch on the sides, and the top and bottom have tons of material to hold onto. Its very strong and rugged!
I wanted an Ar15 stock adapter, since the adjustable LOP stock makes MUCH more sense to me than a folding stock, and I already had a Magpul CTR laying around ready to be used for something, so why not?
Its made of 6061-T6 Aluminum, and unfortunately I had to paint it black, since the anodizing place I emailed never returned my emails
. In any case, it looks just as good.The sling plate at the back is recessed into the block, and allows the use of an HK-clip single point sling, fully ambidextrous, and doesn't interfere with your hand at all. Awesome setup IMHO. Rather than messing with the metric threads for the screws, I ripped apart the OLD USC stock, and took the steel threaded insert out, and press fit, epoxied, and pinned the insert in. Its ridged for the plastic, so i made the hole EVER SO SLIGHTLY smaller, so I had to use a vice to press fit it in. Its ROCK SOLID! aint going anywhere!
I got a half-barrel blank that my friend got for some handgun barrels, and had his machinist copy my USC barrel except for the length, which is the normal 8" UMP barrel length (or 7.87). All I need is to bring it back and get it threaded (I wanted to test the crown before I got it threaded and completed). Going to get it threaded for the 16x1mm RH thread same as my Mark23, since I already have a flash suppressor for it, and a fake suppressor for pics. Groups pretty damn well, my buddy was making some 5-shot-touching groups at 25 yards, and I was killing a piece of 2x4 hanging on a string at 50 yards! SO much fun to shoot!
You can see the sling point on this one.
Closeup of the stock block. Note that since it was painted, I had to scrape some paint off since the tolerances are VERY tight on it.
Put a hundred rounds through it with no problems at all. I only had 1 5/10 round mag with the spacers on it, so it was kinda hard to keep loading it up after 5 shots. Now Im waiting on some 5/25 UMP mags!
ETA
Some info on the stock block, and the stock. There is just enough room for the AR15 stock to go into the rear of the USC receiver and have some good meat on it. There is about 1/8th of an inch on the sides, and the top and bottom have tons of material to hold onto. Its very strong and rugged!
