Before anybody has an aneurysm, no original parts where harmed in the making of this range toy. 20 minutes with hand-tools and it can be returned to the original long barreled, full stocked configuration.
This started life as any other AP-80 imported by bingham, but was converted to full auto in '84 or '85. It is of course, a .22 caliber AK-47 look-a-like made in Italy.
What it looked like when I got it:
This whole process started because I didn't like having to use an adapter to run a suppressor, so I was thinking about chopping the barrel back and rethreading it to 1/2x28. Then I started wondering how far I could chop it, and eventually wondering if I could chop it short enough to keep .22 bulk pack subsonic.
I photochopped a concept together:
Then I spent some time and energy getting the gun to run reliably in it's original form.
Things I did:
Lengthen bolt stroke about 1/2"
Made custom firing pin and heat treat properly
Replaced firing pin spring to work with new FP design
Polish hammer surface that contacts bolt
Polish bolt rails and contact areas
Made Tungsten anti-bounce weight (reverted to steel, the tungsten was too heavy for reliable function)
Replaced recoil spring with new old stock
Replaced hammer spring with part from McMaster Carr
Sharpened and reshaped extractor for better grab
Reshaped all magazine feed lips for better feed angle.
Stripped and cleaned and lubed all mags, polished followers and adjusted springs.
With that work, the gun went from about 40-50% reliable, to about 95-98%. That's as good as any other .22 machine gun I've fired, so I felt like that was a good place to be.
And then in the last 72 hours, I built this:
The stock bolts in place with an angled adapter to keep it's orientation correct, it screws into the original rear trunnion's factory threaded hole for the wood stock. Cheek weld is a little low for the red dot, but with a chin weld, it works.
The barrel was from a parts kit, and was chopped to 5" and threaded concentric to the bore (which was good, the bore was almost .050 off center from the contour!) I also ran my custom chamber reamer through it, polished the chamber and lapped the bore.
The MRDS mount was made from .25" aluminum, and uses the original pin and a series of set screws to hold rigid and adjust gross elevation. The docter red dot will do for keeping me on target (I hope). I may make another one in the future to cantilever the MRDS back about an inch, and down about 1/4" to improve sight picture when using the folding stock.
The K-grip uses an aluminum tube over the barrel with set screws to hold it in place, and the pistol grip from the parts kit is reversed and bolted to the tube. I screwed up one of the dimensions on this one, so I need to redo it, but it'll be pretty close to this in it's final iteration I think.
This started life as any other AP-80 imported by bingham, but was converted to full auto in '84 or '85. It is of course, a .22 caliber AK-47 look-a-like made in Italy.
What it looked like when I got it:
This whole process started because I didn't like having to use an adapter to run a suppressor, so I was thinking about chopping the barrel back and rethreading it to 1/2x28. Then I started wondering how far I could chop it, and eventually wondering if I could chop it short enough to keep .22 bulk pack subsonic.
I photochopped a concept together:
Then I spent some time and energy getting the gun to run reliably in it's original form.
Things I did:
Lengthen bolt stroke about 1/2"
Made custom firing pin and heat treat properly
Replaced firing pin spring to work with new FP design
Polish hammer surface that contacts bolt
Polish bolt rails and contact areas
Made Tungsten anti-bounce weight (reverted to steel, the tungsten was too heavy for reliable function)
Replaced recoil spring with new old stock
Replaced hammer spring with part from McMaster Carr
Sharpened and reshaped extractor for better grab
Reshaped all magazine feed lips for better feed angle.
Stripped and cleaned and lubed all mags, polished followers and adjusted springs.
With that work, the gun went from about 40-50% reliable, to about 95-98%. That's as good as any other .22 machine gun I've fired, so I felt like that was a good place to be.
And then in the last 72 hours, I built this:
The stock bolts in place with an angled adapter to keep it's orientation correct, it screws into the original rear trunnion's factory threaded hole for the wood stock. Cheek weld is a little low for the red dot, but with a chin weld, it works.
The barrel was from a parts kit, and was chopped to 5" and threaded concentric to the bore (which was good, the bore was almost .050 off center from the contour!) I also ran my custom chamber reamer through it, polished the chamber and lapped the bore.
The MRDS mount was made from .25" aluminum, and uses the original pin and a series of set screws to hold rigid and adjust gross elevation. The docter red dot will do for keeping me on target (I hope). I may make another one in the future to cantilever the MRDS back about an inch, and down about 1/4" to improve sight picture when using the folding stock.
The K-grip uses an aluminum tube over the barrel with set screws to hold it in place, and the pistol grip from the parts kit is reversed and bolted to the tube. I screwed up one of the dimensions on this one, so I need to redo it, but it'll be pretty close to this in it's final iteration I think.
