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MAK 90 rebuild - gun pr0n

Posted: Sun, 15 Sep 2013 18:41:25
by UnderwaterMike
Some of you may recall me asking for tips last fall on working on my Norinco AK clone. Well, I finally got the thing done. My original project, which was simply to thread the muzzle for a break, turned into a complete refinish, with new furniture and 922(r) parts to keep everything legal.

I wanted to post pix along the way, but I lost the "before" shots and everything with the finish stripped. (I blasted with 120-grit aluminum oxide to take everything down to bare metal.) But I'm pretty sure everyone knows what a MAK looks like anyway, so here are some pix of the refinished original parts. I used KG Gun Kote 2400 in FDE on everything except the bolt carrier and piston, which were finished in flat black.

Please forgive the lighting. These were shot late in the afternoon on my front walk. The angle of the sun makes some of the parts appear slightly warmer in color, depending on the angle at which they're reflecting light. But everything matches under even lighting conditions.

Original Chinese parts:
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Detail on bolt and receiver:
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Muzzle threading in 1/2 x 28 RH:
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I'll add to the thread as I reassemble everything in the next couple days.

Re: MAK 90 rebuild - gun pr0n

Posted: Sun, 15 Sep 2013 19:07:20
by OakRidgeStars
Looks good. What will the finish be on the furniture? I'm assuming it will be wood instead of plastic.

Re: MAK 90 rebuild - gun pr0n

Posted: Sun, 15 Sep 2013 19:09:35
by gunderwood
Looking good!

Re: MAK 90 rebuild - gun pr0n

Posted: Sun, 15 Sep 2013 19:17:30
by GeneFrenkle
Looks like you even did the inside of the receiver. Looks really good! I'm presuming the piston was chromed - how'd the gunkote stick? Did you have to do anything special?

[ Post made via Mobile Device ] Image

Re: MAK 90 rebuild - gun pr0n

Posted: Sun, 15 Sep 2013 20:01:13
by UnderwaterMike
OakRidgeStars wrote:Looks good. What will the finish be on the furniture? I'm assuming it will be wood instead of plastic.
Nope, going black plastic with aluminum quad rail. My AR-platform guns are the ones I want to keep true to form. This thing is strictly for having fun at the range.
GeneFrenkle wrote:Looks like you even did the inside of the receiver. Looks really good! I'm presuming the piston was chromed - how'd the gunkote stick? Did you have to do anything special?
Yup. Only parts that were not refinished were the inside of the barrel (obviously), and the barrel exterior underneath the gas block and front sight. I just don't have the tools to remove and replace the latter items properly. Ironically, I just got rid of some of that stuff a couple years ago after not using it since the early 90s.
:roll:

Piston was indeed chromed, but that just took a bit more time/care in the blasting. That's one of the reasons this has taken me so long: I started in May, but I had to redo the finish a couple times until I got it the way I wanted. I almost went for a camo pattern, but realized that I'd enjoy the rifle more at the range than endlessly painting it in my garage. Plus, with the impending separation/move, I don't really have anywhere to continue messing with it.

The Gun Kote adheres well, especially after using the K-Phos quickie phosphating treatment. Not as good as a full parkerizing, but a lot faster, neater and cheaper. And it works well.

Re: MAK 90 rebuild - gun pr0n

Posted: Mon, 16 Sep 2013 20:50:24
by Jakeiscrazy
Nice! Looks great!

Re: MAK 90 rebuild - gun pr0n

Posted: Tue, 17 Sep 2013 12:51:23
by UnderwaterMike
In oiling the gun for reassembly today, I found a couple spots where the Gun Kot is not as thick a coating as it should be; i.e., I can see some of the metal color showing through. I thought about degreasing and trying to re-coat those spots. But all my equipment is cleaned and put away, and the surface prep would be a PITA at this stage. Since I did the cold phosphating as a primer, and since this is a protected spot (underside of the barrel underneath the lower handguard), I think I'm going to wait until wear and tear makes respraying the entire thing a necessity. After farting for a month with this thing, I'm OVER the painting!

BTW, this was a fantastic learning project. I may have to look for other guns to refinish. :whistle:

Re: MAK 90 rebuild - gun pr0n

Posted: Tue, 17 Sep 2013 13:48:57
by OakRidgeStars
I'm curious to see if the coating on the gas piston stays put or delaminates after use. Seems like the chrome would stay cleaner but time will tell.

Re: MAK 90 rebuild - updated pix

Posted: Fri, 20 Sep 2013 09:31:13
by UnderwaterMike
So, here's the outcome. First, some updated pix:

Bolt carrier detail:
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Trigger group detail:
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Et voila, the finished product (sorry for all the clutter in the picture):
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Overall, few issues. Problems to note:

1) I beat the hell out of the front sight getting it back together. Not worth stripping and refinishing now, but I will at some point in the future, since it's taken off the paint:
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That was a killer for me, because I go nuts for a flawless paint job. :D You can also see how my very tight-fitting safety selector has already scratched the coating, just as it did to the original surface. I thought about trying to bend that a bit before installing to loosen it. But, I figured that on such a slopping fitting gun, anything that was so tight must be that way for a reason, so I left it as it was.


2) The handguard comes with a set of spacers for the front and back ends which, in the case of the back end, serves to seal off the opening in the receiver underneath the chamber (see below, where I'm holding the piece in my hand, and the gap in the receiver, about 5:00 of the piece and just to the left of the vertical grip):
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The problem I had is that, like many AKs, mine is not an exact length/fit. So, the only way I could lock the lower handguard retaining collar into the notch in the barrel was to remove both the front and back spacers from the handguard. Not the end of the world, since the receiver has other gaps anyway, but I am a stickler for putting things together correctly. If I have the patience when I refinish this gun again, I will probably grind down the handguard edge a smidge so that I can fit the spacers in -- although, by that time, I probably will have lost the spacers.


Overall, including tools, supplies and parts, it cost me about $300 to rebuild this gun from stock fugly as purchased in 1991. That's a bit more than outsourced Parkerizing would have been. But, I also got threads, brake, handguard, stock and cheap red-dot. And, I learned a hell of a lot about refinishing AK-pattern guns. So, all in all, a pretty good deal.

I hope to get to a range this weekend and zero both the irons and the red dot.

Lemme know if you have questions on the process or on Gun Kote. In fact, if I can establish a decent workspace after I find an apartment, I may start doing paid Gun Kote refinishing as a side gig. About $500 in equipment is all I need to supplement what I already bought to get to a pro-level setup.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 20 Sep 2013 09:33:12
by UnderwaterMike
BTW, I did already get some chipping on the piston rings, so I went nuts with a steel brush on a Dremel and removed any remaining loose bits, and burnished the rest. Not much came off, so I think it was probably a result of me failing to adequately prep the surface, rather than the coating durability per se.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 20 Sep 2013 09:43:40
by UnderwaterMike
Also, I started using FIREClean on this gun, rather than the usual grease and oil. The gun shoots dirty, especially with the crappy Wolf ammo I have for it. I really hope that the FIREClean works as billed, because I don't think it's giving me as much lubrication on the bolt and carrier as the grease normally would, which will wear both the finish and parts. I guess I'll just have to try it for a while and see.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 20 Sep 2013 10:01:45
by GeneFrenkle
I think the slight chipping gives it a really nice character and would encourage you to keep it that way unless it exposes unprotected metal and invites corrosion. Rifles that look "too good" make me wonder if they're just safe queens and never get to have fun.

It's really a striking rifle.

Re: MAK 90 rebuild - gun pr0n

Posted: Sun, 22 Sep 2013 10:01:49
by UnderwaterMike
Thanks! :D

I had some trouble trying to zero the scope on FRI. First time I've ever had a red dot, and the laser boresighter was not working well in the bright sunlight. I may have it close, but I need a gun rest that will really hold this thing tight -- my bargain lead Sled Solo doesn't grab it tightly enough.

Re: MAK 90 rebuild - gun pr0n

Posted: Tue, 22 Oct 2013 19:39:00
by safaridave
I have a MAK90 that needs to be rebuilt too.... except this one needs a new receiver bent and riveted. Anyone out there with a press and AK building setup? I have done two AK from Romy G parts kits, but would like to do up this one too.
This MAK90 is a sad story... I used to live in CA and let the "Assault Weapon" registration date slip by me, and I had to cut the receiver up to stay legal. Now that I live HERE though... its time to bring her back to life. Anyone willing to help with this charity case?
Safaridave

Re: MAK 90 rebuild - gun pr0n

Posted: Tue, 22 Oct 2013 20:06:08
by UnderwaterMike
safaridave wrote:This MAK90 is a sad story... I used to live in CA and let the "Assault Weapon" registration date slip by me, and I had to cut the receiver up to stay legal. Now that I live HERE though... its time to bring her back to life. Anyone willing to help with this charity case?
Safaridave
OUCH! :out_cold:

I don't have the equipment to help with the receiver, but I'm happy to answer any questions you have along the way. This project actually gave me enough confidence to start refinishing guns for others, once I can get some additional equipment.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 25 Oct 2013 13:54:50
by 762
I'd be interested in building up some kits, too. I have the jaws for the rivet squeezer method.

You could get an already bent receiver (80%) and have it heat treated, then drill the holes for it.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 25 Oct 2013 14:17:59
by bryanrheem
so are you just doing all of this work out of your garage? Very impressive!

I've have enough success zeroing red dots with a good amount of sand bags.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 25 Oct 2013 14:27:22
by UnderwaterMike
bryanrheem wrote:so are you just doing all of this work out of your garage? Very impressive!
Me? Yes. If I can get some customers, I'm going to upgrade my equipment (e.g., blast cabinet, bigger compressor) to speed up the process. It'll cost about $1200, but no sense doing that if it's not going to get any use.

Re: MAK 90 rebuild - gun pr0n

Posted: Fri, 25 Oct 2013 15:31:31
by OakRidgeStars
Thought I would post this link to the "Soup to Nuts" articles for those who might not have seen it before. You will need to download the .PDF file for each section (1 - 5) since the web version no longer has pictures.

http://www.surplusrifle.com/shooting200 ... /index.asp
http://www.surplusrifle.com/shooting200 ... /index.asp
http://www.surplusrifle.com/shooting200 ... /index.asp
http://www.surplusrifle.com/shooting200 ... /index.asp
http://www.surplusrifle.com/shooting200 ... /index.asp