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View Full Version : AK build questions (looking for an AK for dummies guide)


drclark
11-30-2006, 4:44 PM
OK, I finally decided to try to build my own AK-pattern rifle. I bought an NDS-3 from CWS at the costa mesa show and am currently waiting to pick it up. I have been researching here and other forums. I would like to summarize what I have learned (or think I have learned) and have a few questions for those here who have already built their own AK's.

Receiver : NDS-3
Parts Kit : I intend to buy a Romanian-G kit.

First question: what is the difference between the standard and G2 triggers? I understand that I will have to cut a 2nd notch in the bottom of my receiver if I go with the G2 trigger. What are the real benefits and is a G2 trigger worth the extra cost and effort? If I use the trigger as part of the US parts compliance, should I get a standard kit and get a US-made G2 trigger group rather than paying extra $$ for a parts kit that has a G2 trigger already?

Build methods: There appear to be 3 popular build methods; rivets, screws, u-drive "screws". All have advantages and drawbacks. For all build types, parts kit must be "de-milled". In otherwords, rivets holding trunions, trigger guard, etc must be ground/drilled out allowing the valuable parts to be separated from the receiver stubs. Welding the receiver to the demilled trunions is another option. I do not have access to a welder so I am going to skip this method for now.

Rivets: Front and rear trunions are attached to the receiver using rivets. the old rivets must be drilled out completely. In order to do a rivet build, the barrel must be pulled out of the front trunion (in-order to have clearance for the rivet crush tool). Removing the barrel pin may require a hydraulic press or at the very least a hefty vice. Pulling the barrel may require a pulley removal tool that is obtainable from most auto parts stores. Intalling the new rivets requires some specialized tools. Modified bolt cutters can be used as rivet crush tools. There are other more specialized tools also available. Some riveting methods can be done "cold". Other riveting methods require the rivet to be heated prior to being installed. I think I read somewhere that if heating the rivets, the barrel is not required to be removed since it is effectively used as a "bucking-bar" for the hot rivet to smush against.

Advantages: Most durable type of build. Most authentic appearance.
Disadvantages: Most difficult type of build. Requires specialized tools for insertion of new rivets. Requires barrel removal. Requires headspacing the barrel upon re-installation?

Screws: Front and rear trunions are attached to the receiver using hex-head machine screws. In order to do a screw build the original rivets are drilled out. The rivet holes are then drilled and tapped for the machine screws. Since barrel removal is not required, the only specialized tools required is the thread-tap. Tap used should be a "bottom" tap to allow threads to be tapped all the way to the bottom of the hole.

Advantages: Less effort and specialized tools required than rivet build. Barrel removal not required elimiating the need to deal with head-spacing the bolt/barrel (is this a valid statement or is a headspace check required for any type of build?) Durable build (provided some sort of thread locking compound is used)
Disadvantages: Still need to buy thread-tap. Need to be careful not to snap tap off in receiver while cutting threads.

U-drive: Front and rear trunions are attached to the receiver using u-drive screws. U-drive screws are self-tapping screws that are rivet-like in appearance. Hole is drilled into rivet-stub (or rivet is completely drilled out). U-drive screw is then pressed/hammered into hole to attach trunion to receiver. Again, barrel removal is not required, and only tools needed are a drill to remove the rivet and a hammer (or vice) to press the u-drive in.

Advantages: Easiest build type. Required only basic tools that most anyone should have readily available. Looks more authentic than screws. Barrel removal is not required eliminating headspace issues (again see question above).
Disadvantages: Possible long-term durability questions???

I am currently leaning toward a u-drive build. I am only planning on doing 1 build so I do not want to invest $$ in specialized tools required to to a rivet or screw build. Has anyone here tried doing a u-drive build? If so, are there any issues I should be aware of in terms of build difficulties or long term reliability.

SB-23 compliance:
Completed rifle must comply with SB-23 features list or have a fixed magazine. Popular ways to to accomplish include fixing the magazine using a bolt drilled and tapped through the magazine release rendering it inoperable, going gripless or using a monsterman-AK grip or other compliant grip option (thumb-hole stock with hole permanently filled in). A less popular way would be to convert the receiver to a "saiga-style" trigger and conventional stock. Of all the AK builds that have been done, what is the consensus as the best approach to SB-23 compliance. My intent is to use the rifle as a plinker shooting from off-hand or unsupported positions most of the time. I am currently leaning toward a monsterman type grip at this time.

US parts compliance:
In order to avoid issues with 922 "non-sporting" imports, home built AK type rifles have to have a minimum count of US made parts. The receiver counts as one part. Are there vendors that offer a us parts compliance kit or do I have to buy each part individually? If buying in a kit or individually, what type or records do I need to maintain to prove the rifle has the minimum number of US parts?

*update* Since the sunset of the crime bill it is now legal to assembly a semi-auto ak47from ak47 parts kitsas long as section 922.r is in compliance which requires the use of 6 U.S. manufactured AK-47 component pieces. These specified Ak47 parts include the receiver, gas piston, pistol grip, butt stock, front handguard, flash hider or muzzle brake, trigger, hammer and disconnector

Thanks,
drc

JHC
11-30-2006, 5:35 PM
The G2 trigger comes in both single and double hook, if you get a single hook you wont have to mod the receiver. You can use some of the original trigger group if you mod them but it is much easier to buy the G2 for $35 and get to count them as 3 US parts.

alpine18
11-30-2006, 8:43 PM
First question: what is the difference between the standard and G2 triggers? I understand that I will have to cut a 2nd notch in the bottom of my receiver if I go with the G2 trigger. What are the real benefits and is a G2 trigger worth the extra cost and effort? If I use the trigger as part of the US parts compliance, should I get a standard kit and get a US-made G2 trigger group rather than paying extra $$ for a parts kit that has a G2 trigger already?


Go for the G2, it's a quality part and solves a couple issues with keeping the build legal.

Also, screw builds don't have to use bottoming taps... in fact I would recommend REMOVING the barrel and tapping through the trunnion with a standard tap for a screw build. There is some debate about the strength of screws vs. rivets. Rivets are soft by nature, after all you "squish them" - try doing that with one of those black button head screws.

I am a fan of the hybrid build - screws in front/rear trunnions, rivets in center support and trigger guard.

wilit
11-30-2006, 9:05 PM
These are quite possibly the two best AK build reference pages out there.
http://pookieweb.dyndns.org:61129/AK/ak.htm
http://www.gunsgutsandgod.com/

Here's a best tutorial I could find on doing a U-drive build.
http://www.ar15.com/content/page.html?id=187

There has been some discussion about U-drives backing out on the front trunion because they weren't installed correctly. The best advice I've read is to use lock-tite on the threads before driving them in.

As far as fixing the magazine... I started a thread about this a few weeks ago. If the new proposed regulations are adopted, the screw through the trigger guard won't be legal. What the general concensus was, drilling and tapping a hole in the magazine so a set screw could be installed. This screw would be located on the inside of the receiver so the action would need to be removed to get to the screw. Here's the thread I started. There's pictures of what I'm talking about on page 2 or 3.
http://www.calguns.net/calgunforum/showthread.php?t=41534

Charliegone
11-30-2006, 9:09 PM
I have so far fired about 100 rounds through my u-drive/ rivet hybrid with no problems, other than mag problems (cheapo mags.) They haven't backed out one bit. Still I think it will need more than a 100 rounds to really see how good it is.

JHC
12-01-2006, 4:16 AM
When you hear rumors of Udrives backing out it's most likely where someone tried to cheat and use them on the front trunion in the mag well since there is not enough material there to bite into.

drclark
12-01-2006, 5:09 PM
I was looking at parts kits online at http://www.akparts.com/index.htm

This is the description of the ROMY parts kit from their website and it makes me a bit nervous.

LARGE SUPPLY NOW IN STOCK!! . We just had to show the quality of the latest AKM kits. These Romanian AK-47 kits with Laminated wood furniture are in good to very good condition. Chrome lined bores are inspected 100%. No shot out bores from AKParts.com. Why buy from us? Compare ours to "theirs" MATCHING # BOLT, CARRIER AND BARREL TRUNNION. PARTS ARE GURANTEED ON THESE KITS FOR PROPER HEADSPACE!!. MILITARY SLANT STYLE MUZZLE BRAKE INCLUDED!!. 14/1 LH threaded barrel, bayonet lug, and yes they even have cleaning rods too. OUR KITS INCLUDE CORRECT TRIGGER DISCONNECTOR, "THEIRS" INCLUDE THE WRONG DISCONNECTOR OR IT'S COMPLETELY MISSING!! Includes the semiauto trigger components and can ship anywhere in the US. Receiver not included of course. Std AK-47 caliber 7.62x39 If you want the lower quality nonmatching kits or the cheaper kits with missing disconnector, we have those available as well. from $79.00 and up, email for

Can anyone tell me what "disconnector" this vendor is refering to? No other parts kits I have looked at mention a disconnector. All the assembly instructions for typical G2 triggers I've looked at online do not mention a disconnector. I also notice that this site sells "full auto" hammers and bolts, etc. I am leary of this kit since I could interpret "disconnector" to mean something full-auto related. Has anyone bought parts from this vendor? Am I being overly paranoid?

Has anyone bought parts kits from this vendor before?

Thanks,
drc

Builder
12-01-2006, 5:51 PM
I was looking at parts kits online at http://www.akparts.com/index.htm Can anyone tell me what "disconnector" this vendor is refering to?
Hi Dr. Clark,
Both semi and full triggers have a disconnector. The semi does NOT have a tail extending backwards where the selector can hold this tail down while pulling the trigger. No tail ='s good. The second concern is the diameter of the pin hole through the disconnector. A real AK has a pin diameter of 5 mm and the disconnector has a 5 mm dia hole in it. A small ring spacer is used to hold the disconnector to the left side of the trigger. A disconnector can also have a ≈6.5 mm dia hole sometimes. This type has stepped sleeve that fits inside the disconnector and a larger diameter that acts like the spacer, all in one piece. However, it is a bit of a challenge to get the pin through the trigger, disconnector, either the sleeve or just the spacer ring, through the other side of the trigger, and then into the other side of the receiver because you have to hold pressure against the disconnector spring.
That's where the Tapco G2 fire control group comes in. Their design has the correct disconnector, their sleeve goes all the way across the trigger so you can assemble them as one piece outside of the receiver, and they are US made parts. Just get the Tapco G2 FCG and smile. Even if your parts kit does come with the full auto stuff, just get rid of it as quickly as you can or preferably before you get your receiver.
Have a wonder time building,
Builder

wilit
12-01-2006, 5:55 PM
I was looking at parts kits online at http://www.akparts.com/index.htm

This is the description of the ROMY parts kit from their website and it makes me a bit nervous.



Can anyone tell me what "disconnector" this vendor is refering to? No other parts kits I have looked at mention a disconnector. All the assembly instructions for typical G2 triggers I've looked at online do not mention a disconnector. I also notice that this site sells "full auto" hammers and bolts, etc. I am leary of this kit since I could interpret "disconnector" to mean something full-auto related. Has anyone bought parts from this vendor? Am I being overly paranoid?

Has anyone bought parts kits from this vendor before?

Thanks,
drc

When they say "their kits are missing the disconnector," they mean the original disconnector that the rfile was built with. You'd thow it away anyway because you're using the G2 set to be 922r compliant.

As for the full-auto parts... The disconnector from the SA and FA are the same (AFAIK). What makes an AK or AR full auto is the sear. Your receiver does not have a provision for the sear, nor can you buy one unless you have a class III license.

Builder
12-01-2006, 6:20 PM
The disconnector from the SA and FA are the same (AFAIK). What makes an AK or AR full auto is the sear. Your receiver does not have a provision for the sear,
The FA disconnector has a tail and the SA disconnector doesn't. The triggers and selectors are the same. The FA hammer has a sear near its base (pin area) which engages with the auto sear. The auto sear is forward and below the hammer with an arm that rises to contact the bolt carrier when it is fully forward. The auto sear acts as a disconnector to release the hammer. The bolt carrier has a little tab on the right side under the groove for the receiver carrier rail, but this doesn't matter in SA. The bolts are the same.
Your receiver rail won't have a cut out for the auto sear arm anyway.
Toss the auto sear and tailed disconnector (if you get them) and grind off the sear at the base of the hammer (so you can save it for replacement parts just in case). The G2 is a good choice.
Builder