How to Build an AK-47
Part Two of our series on US AK47 builders
- Matt's home shop AK47 building method

Update 12/23/05
From: http://rtccom.net/~mattb/ak_build.html

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   Yeah I know, it's been over a month since the last update. I've felt more like working on the AK than I have working on the page. :) Lots of new stuff to report. Here's basically where things are now:

1. I GOT A DRILL PRESS! Yes, picked up a new-in-box 1/2hp bench drill press on ebay for cheap. Works great for this job, and I can see me using it a lot more in the future. I've been wanting a drill press for a long time, the AK build was a good excuse to finally get one.

2. Both trunions are drilled and tapped! Woohoo!

3. Drilled out the rivets on the trigger guard/safety stop lever, freeing those two parts from each other. Despite my previous hacking around on this with the hand drill, the parts ended up not being too horribly marred.

4. Started cutting down the trunion screws.......I have one matching the width of the front trunion wall + 1.0mm receiver shell almost perfectly, I will cut the rest of the screws down to this length eventually. Fairly quick job, just haven't got around to it (it won't really need to be done until I get the new receiver in).

5. Got all three wood pieces (upper and lower handguard, and buttstock) stripped, and two coats of Tru-Oil on the upper handguard. Also just put a coat on the buttstock, and put some filler in the crack in the lower handguard.

6. And finally, I got a couple of bayonets.

    Now for some pics and further details on these exciting new developments. :) First, the bayonets. I found a guy on ebay in the UK selling reproduction AK-47 bayonets. They didn't look particularly like any specific bayonet I'm aware of, but they were very nice looking and appeared to have the necessary AK muzzle fittings, which was my main concern. I bid and won one, but he inadvertently sent me two. =O But since I'm gonna be building more AK's, and because I was so impressed with the design and quality of the bayonets, when I notified him of the mistake I offerred to just pay for the second one too and keep them both, instead of sending it back. He let me keep it for a reduced price and didn't charge me for the S&H on the second one, cool! So now I have two bayonets. And here they are...............

Overview

"Dramatic" angle

World's coolest letter opener?

   Only one problem with these babies.....they don't fit my AK. :( The muzzle ring is slightly smaller than the slant muzzle brake on my AK. Without the brake, the bayonets would probably fit fine. I'm told "genuine" AK-47 bayonets are designed to fit snugly over a muzzle with attachments like slant brakes, and fit loosely over a clean muzzle. Apparently whoever designed my bayonets got the muzzle ring diameter a little small. Otherwise it looks like it should fit fine. I may get a stepper bit and try to bore the ring out a bit so that it fits over the brake.

   On to the furniture. I'm pleasantly surprised at how well this part is coming along, I was a bit worried when I initially started stripping the original finish off the wood. As I mentioned in the last update, I'd started sanding the stock but I was planning on using antique furniture refinisher solvent to pull the finish out of the wood. This didn't work out very well........the solvent did loosen up and remove the finish, but it took a LOT of scrubbing. The results weren't really any better than what I got with just a lot of sanding, and actually required more work. So I just went back to heavy sanding. I've decided to not use any chemicals on future kits, just sand everything.

Pic: lower handguard, right side

The lower handguard was my "test article" for the solvent........I scrubbed the entire piece heavily with steel wool while keeping it soaked in solvent. I then sanded it a bunch. I also used my Dremel with a sanding drum to remove some of the partial layers of glue and wood grain visible (the furniture is laminated), as they otherwise made for unsightly large dark areas. If I were staining the furniture this would probably be fine, but as it is I'm just applying an oil finish and then will probably apply a clearcoat for protection and appearance.

Left side

The buttstock got some solvent, but mostly just sanding. I also used the Dremel on this piece to remove dark areas, as on the lower handguard.

   The upper handguard was sanded only, no solvent whatsoever. It seems to be of a different wood type (perhaps not laminated?) than the other pieces, and looks great. After applying the first coat of oil and letting it dry, I scrubbed it lightly with light steel wool and applied another coat. I'm gonna wait and see what the rest of the furniture is going to look like before applying more oil.......I want to keep the wood pretty light in color if I can.

Upper HG, sanded, before applying oil finish

Two coats of finish

   The big news is getting the trunions tapped. I shouldn't have tried drilling them out with a hand drill at first, as I just ended up making it more difficult to drill with the drill press. The hand drill "walked" when trying to drill the rivets out, effectively making an off-center pilot hole. This caused me trouble later on when I drilled them out with the drill press. Still, I actually didn't cut into the trunion much, and pretty much obliterated the old rivets for the most part. The important thing is that after tapping the holes, the screws tightened down nicely with no signs of stripping out the threads in the trunion.

   To tap the trunion holes, I mounted the tap in the drill press. I then popped open the top cover (normally used to adjust the belt for different speeds), and hand-cranked the pulley that's mounted to the shaft that the chuck is on. I read on a forum somewhere about someone using the drill press to hold the tap, and I really felt better with this method as opposed to mounting it in a conventional tap handle and trying to keep the tap vertical by hand. Mounting the tap in the press ensures it stays vertical to the trunion.

Pic: Trunion/barrel assembly in the drill press

   The trunion is basically a big block of steel that the barrel is pressed into. According to one builder's website, the trunion walls next to the barrel are about 0.10" thick, and there's a gap of about 0.09" between the inside of this wall and the outer surface of the barrel at the chamber. Unfortunately I managed to exceed this on three of the four holes and drilled into the barrel slightly. :( Basically it's just a "nick" in the outer wall of the barrel, I don't believe it has caused any dangerous weakening of the chamber area. It occurred to me later that since I was cutting down the screws anyway, I didn't need to go nearly as far as I did anyway, just as long as I got through the trunion wall and sufficiently cleared out the old rivets. Lesson learned, and another good excuse to build another AK. :)

   It is possible to punch out the barrel retaining pin, and press/hammer out the barrel before doing all this, then pressing the barrel and retaining pin back in later, but then you run the risk of throwing off headspace, which can be QUITE dangerous. Since I'm not experienced in this stuff, and have no way to accurately check headspace after reinstalling the barrel, I opted to leave it in.

One more pic......my way cool drill press :)

   That's all for now. Hopefully by the next update I will have the receiver. It's probably gonna be sometime after the end of the year before it gets here, the place that makes them is back-ordered pretty badly. But it's now the 23rd, so maybe in a couple weeks I'll have it! After that I will have everything I need to complete this project (though I need to purchase some clear coat for the furniture, but no big deal there). The last hurdle will be accurately transferring the trunion hole pattern to the new receiver and drilling it out. This is pretty critical, as the receiver needs to be parallel to the barrel to ensure that the next round approaches the chamber squarely, and the bolt head seats flat against the chambered round (plus it would just look funky if the barrel was like, drooping or something, in relation to the rest of the gun, even if it was just off by a bit).

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