I'm going to be editing my posts under this topic to try to clear them up and hopefully help anyone who runs into this in the future.

Original post follows:

I was going to post a thread yesterday asking if anyone had used the Desert Fox Outfitters adapter to use AR stocks on a milled receiver MAK-90.  I had been thinking about ordering one for a while, but had not seen any pictures of that specific adapter in use.

I found this thread where tac556 mentioned that he had used one.

https://www.ar15.com/forums/AK-47/What-to-do-with-a-neutered-MAK-90-slant-cut-with-thumb-hole-stock-/78-170400/

I went ahead and ordered the adapter from Desert Fox Outfitters and an AR stock kit from PSA.  As I drifted off to sleep last night, it occurred to me that I would need a pistol grip as well.

Is there any difference between a pistol grip for a milled receiver MAK-90 vs. a stamped receiver?  I already have my MAK-90 in a black plastic thumbhole stock, so I already have black handguards.  The AR stock I ordered is also black, so I'd like to get a black pistol grip as well.  I just wanted to verify if any AK pistol grip would work, or if I would need to get something specific for a milled receiver.

I've been finding a few that say "for AK pattern rifles" without specifying milled or stamped, and a few that say "for stamped receivers", which I guess would eliminate milled since they specify.

The only one I see (so far) that says "milled" is from Arsenal.

https://www.arsenalinc.com/usa/pistol-grip-ak-47-milled-and-stamped-receivers-metal-insert-reinforced-polymer-matte-black.html

At least I know this one is an option.

AK grips are interchangeable between stamped and milled guns.  The stamped gun has a drop in threaded insert for the screw to thread into, while a stamped gun has a riveted on part that is threaded.  But the grip and screw are the same.

Thanks!

Well, this isn't going as well as I'd hoped.

The Desert Fox Outfitters adapter has a piece like a half-circle that the bolt goes through on the inside.  It's supposed to fit snugly in the rear of the inside of the receiver.  My receiver has had more material milled away than whatever receiver they used for a reference.  The part goes right through.  I'm in the middle of fabricating an insert.  So far it seems like it will work.

Pic from their site:


Then the pistol grip.  See next post.

Editing this post for additional information and trying to clear some things up.

I had no idea a pistol grip would be this much of a headache.

I ordered a black polymer grip from Arsenal.  The had one that specifically said for stamped receivers, and one that said for stamped or milled.  They had different part numbers, so I ordered the one for a milled receiver, just in case.  The description stated that part AK-NSK was "necessary".  This part number is for two items - a screw (AK-045) and nut (AK-013US).  I did not order the screw and nut because I had the ones from my original thumbhole stock.  The screw I had was 4".  The screw with part number AK-045 is also 4".  Mine should work then, right?

Wrong.

The grip arrived, and my screw was too short.  I checked to see if Arsenal sells a longer screw, and they do.  Part AK-045L is 4.5".  The one Arsenal sells that is 4.5" is for thumbhole stocks.  The one in my thumbholes stock was 4".

This is why I have trust issues.

I went by the local Home Depot and found a screw that had the correct dimensions according to my searches (M6-1.0x110mm).  The cap at the end turned out to be too wide to fit in the hole in the grip.

I searched for grip screws and found very few websites actually list the dimensions.  I ended up going with Polytech Parts because they listed theirs as 4.5".  It arrived today, and is the exact dimensions (except for the length of the threaded section) as the one I bought at Home Depot, so the cap is also too wide.

I took some measurements.  The cap on my original screw is 7.9mm wide.  The cap on the screws from Home Depot and Polytech Parts are both 10mm wide.  The recessed hole in the pistol grip is 8.5mm wide.

I'm trying to decide if I should:

Widen the hole in the pistol grip
File down the cap on one of the 4.5" screws I already bought
Pay Arsenal $16 for a 4.5" screw to be shipped

Throw the bolt into a drill press, and hit it with a file to turn down the head diameter.  

Not sure what bolt you have, but there are allen head bolts which fit just fine in every AK grip I have seen.  Try a specialty fastener store if you don’t want to turn down the bolt head I guess.

Don’t know what to say about the the retention piece not fitting inside the receiver, but the Chinese milling that back end out inconsistently would not surprise me.  I didn’t need to modify it on mine, just needed to fit the adapter piece a little with a file so it would fit inside the receiver better.

I was in the middle of editing my post to clear some things up when you replied.

The caps at the ends of both bolts (Home Depot and Polytech Parts) are 10mm wide.  The hole in the Arsenal grip is 8.5mm wide.

Since I spent the least amount of money (so far) on the bolt from Home Depot, I'm going to try what you suggested and see if I can shave it down to fit.

Thanks for the reply!

I have a working screw now.

I found a gun shop 20 minutes away that had the Arsenal 4.5" screw in stock.  I never knew that shop was there.  The guy at the counter says he gets that a lot...