Looking good! Thanks for sharing.
Herein describes the entire process for building an parts kit into a functioning firearm. For this build I choose a Polish Tantal wz.88 which is Kalishkanov based design with some cosmetic differences and a modified fire control mechanism. This is a draft of a blog entry so the audience is not necessary you guys who can do half this stuff in your sleep, but bare with me.
First I started with an AK-Builder Tantal flat. Curtis is the only provider of flats made for Tantals. The Tantal flats have different safety selector holes and stampings. Curtis warns users of the flat to extend the selector markings in the flat bending jig, but I found I could push the flat forward and still fit the selector and magwell dimples within the bend plates.
The BATFE believes that everybody who builds their own firearm and ever allows the firearm to leave their possession should mark the firearm with the required 27CFR478.92 markings, even though the regulations clearly state that they only apply to "licensed manufacturers" of which I am neither. Since I may want to sell, trade, give or lend the Tantal in the future, I go ahead and cover my tail and do so. Stampings are easier to do before the flat is bent so it's the first thing done. The flat bending jig, dissaembled, turns into a nice steel backing for the stamping. A bar is clamped to form a straight line to stamp against.
Next, the flat is secured in the flat bending jig.
And the undersized of the exposed flat is covered in petroleum jelly to minimize scratching.
The assembled flat jig is placed in the press and bent. Technically, a new firearm has been born. This is where the Brady bunch and UN global gun control advocates start foaming at the mouth.
Next the rails are bent.
The rails usually do not get bent flat. The are finished with flat bar stock and a hammer.
Next the jig is placed in atop a vice so that the middle section can drop down with some hammer encouragement. Make sure to do this over the table or watch your toes!
I dn't like to overitghten the flat bender on the magwell because I sually lose the mag catch stamping. Sometimes the magwell doesn't fully form, in that case, it and the trigger guard rivets needs to be carefully hammered into shape with flat bar stock and a hammer.
Now that bent flat can be removed. I had to go back and straighten out the bottom a bit more..
Soon the receiver will be ready to start accepting parts, the so the parts kit must be completely demilled. Some parts kits still have pieces of the receiver attached, but this Polish kit had the receiver completely removed. Still, the barrel needs to be removed and the rivet stubs drilled out.
To start on the barrel, first the barrel pin is removed.
After removing the barrel pin, the inside the barrel pin hole is lightly filed with a rat tail file to clean up the intersection between the trunion and the barrel. This helps prevent upper-barrel gouging while the barrel is being removed.
The barrel is pressed out using a bolt and a stack of pennies to protect the breech face.
All rivets are removed from the trunions and trigger guard. This is done by centerpunching the rivet stub, drilling a small pilot hole, drilling a larger hole through the entire rivet and then punching the rivet out. Motor oil is applied druing the drilling. This takes time as there are 11 short rivets and 2 long rivets.
Back to the receiver, the rails need trimming to fit the trunions. I have a 100% Global Trades receiver handy, so I used to to mark the rails with a permament marker.
The black area is what will be removed to fit the front trunion.
Something I came up with to trim the rails good and straight made up of a vice, an I-bar clamp, a sliding vice and a dremel.
But I didn't feel like setting it up, and they can be cut by hand.
The rails are filed smooth to fit.
After trimming the rest of the rails, using another completed receiver as a guide, the trunion hole locations are measured, marked and centerpunched. The can then be drilled. Like demilling rivets, first drill a pilot hole then the finished hole. The holes are drilled slightly undersized.
The holes are finished by inserting the trunion, clamping the receiver and drilling into the holes with a hand drill. The receiver metal is much softer then the trunion metal so the drill bit will walk to drill the receiver hole in the correct location and size.
All of the trunion rivet holes are countersunk on the Tantal. I countersink by inserting a wood screw and hammering it with a punch.
Now the trunions are riveted to the receiver using my modified Plinker's jig and the press.
Usually I wait until last to rivet the rear trunion but I got ahead of myself on this build. The rivet closes to the camera came out well, the one further back, not so well.
The lower portion of the side rails are trimmed to fit a magazine between them.
Now the rails are secured for spotwelding. Using a letter guage drill bit set, the size drill bit that fits snugly into the front trunion rails are selected to align the rails. The rails are clamped in place until the first two spotwelds are applied, which will secure the rail.
The center support tube and rivet are installed.
The center support rivet is tricky. If you try to press it, it will most likely shear to one side or ther other you end up with a real mess of a rivet. I finally learned to mushroom the rivet with a hammer first. This is done by stricking the rivet with glancing blows in different directions.
I mentioned earlier how I installed the rear trunion early. So I reverted the method of removing/pressing barrels that I used before I got a press. This I learned from hcpookie. The I-bar clamp is placed in the vice and the barrel is inserted into the trunion. After checking that the barrel is traight, the receiver and abrrel are placed in the clamp. A piece of aluminum is placed between the clamp and the muzzle. The clamp is tightened. This causes the barrel/trunion intersection to rise. The trunion is hit with a rubber mallet and the barrel scoots further into the trunion. The barrel is inserted in small steps. The I-bar clamp is never pushing very hard, just enough to tense the fixture so that the trunion can be hit with the mallet.
Towards the end, the barrel pin hole is watched to know when to stop.
The trigger guard is riveted. This jig can do all four front rivets at once, but I usally do two at a time. This jig has to be pressed on real hard to get the rivets to fully seat the trigger guard and selector stop.
My first real complaint with the flat, the pistol grip hole didn't line up with the side folder latch spring plate. I grinded the grip nut to fit.
Now the furnature is installed for the photo op.
The firearm is not not complete. I am still waiting on my 5mm and 7mm reamers to arrive, which are necessary in the Ak builder flat to finish the trigger group in holes. Also, the gas piston needs to be replaced. The US parts for this build are the AKBuilder flat, flak38 wood furnature, hotbarrel muzzle brake & piston and I will be replacing one of the trigger group components.
An update including gas pison, FCG and metal refinishing when it's done!
Looking good! Thanks for sharing.
"To show you how radical I am, I want carjackers dead. I want rapists dead. I want burglars dead. I want child molesters dead. I want the bad guys dead. No court case. No parole. No early release. I want 'em dead. Get a gun and when they attack you, shoot 'em."
Ted Nugent - speaking at the NRA convention April 17, 2005
Great info. That furniture from Flak88 looks nice.
Why did you grind the grip nut when the flat would have been easier in my thinking? How far off was it?
Freedom is not free. Some will perish to preserve it for the many. Just as our Forefathers did before us, we must take up the battle and not waver. Victory is our only option.
When you use that flat jig to bend the flat don't press on the center bar. Use a piece of steel on top of the two angle pieces and it will work out much better.
Something must be off because the grip nut opening is fine on my Tantal that was tested before those flats were made. The hole could be moved forward .040" to .050" on the next run of flats, but as it is now it is fine.
DO NOT MOVE THE FLAT FORWARD IN THE JIG TO CLEAR THE DIMPLES!! Get out a dremel tool and grind that small area open.
Moving the flat will make the front and rear dimensions of the receiver off. It may work, but it's not the best way to do it.
Roger that Curtis. Will do for my other Tantal. I just picked up a carbide dremel end piece that can extend the selector recess. I see what you're saying how moving the flat could mess up with the height of the receiver. I'm still waiting on my 5.45 ammo to arrive, so I'll find out soon how much the AK is tolerance to spec! I did put some 5.5.6 ammo in the magazine and it stripped them fine.
rbthntr64: I grinded the pistol grip nut because I didn't have a file small enough and mean enough to grind the receiver. The fit was "almost there" so I only took a little bit off. For this build, the fit is tight and snug which is what is important.
Looks great. Thanks for sharing
You make it look so easy!
Are you going to heat treat the flat?
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