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Posted: 9/15/2025 3:55:57 AM EDT
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Anyone ever needed to work on a chinese feed ramp for FMJ feeding? Have a MAK-90 that has spent the last 20 yrs in the back of a safe without furniture on it, never fired it myself, finally put it back together and it does not want to feed FMJ out of a couple Euro steel surplus mags. Lots of copper build up on the feed ramp. (Can’t recall if I tried a chinese mag or not but it really shouldn’t matter obviously). Ammo was basic Russian or Euro (Wolf I think), nothing oddball about the projectile geometry or cartridge OAL. Now I do recall having done a little feed ramp work on various chinese AK’s to help them feed HP ammo better, but I have never seen this happen with any FMJ ammo. Honestly I don’t even remember what exactly I did 20 some years ago on those other rifles to fix or improve the issue. But it was always the chinese guns, never Euro patterns that had trouble with HP ammo in my recollection. |
a loaded gun won’t set you free, so you say…
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Think I figured out which mags they were, not helped by the fact that I several different range boxes of 7.62 AK range mags… #1 was a Romanian surplus mag in excellent shape. #2 is most a well used likely Polish mag, or one of the similar Euro pattern, no markings to help me narrow it down better though. Both are actual surplus military, not made for the commercial market stuff, mags that I have had for a long time. I looked at a number of various AK’s and noticed that the bullet guide on the MAK-90 and several earlier model Chinese stamped 16” guns is shorter length- there is a noticeable gap between the locking lugs and the start of the guide. Meanwhile milled Chinese, chinese stamped 20” NHM-91, and Euro pattern in both stamped and milled have bullet guides that extend much closer to the locking lugs. Not sure why they are different, but it is a also noticeably different guide style as well as extending less towards the mag well. And I didn’t see evidence of me actually doing much work on the bullet guide of any of my chinese models. I may have just decided to stay with FMJ on them. Looks like I worked on a Romanian though. (I think- been a couple decades like I said)….. Mags in question: Attached File Ammo used: Attached File MAK-90 short bullet guide: Attached File NHM-91 long bullet guide: Attached File MAK90 short bullet guide from side angle: Attached File NHM-91 bullet guide from side angle: Attached File Notice that those guides are nothing at all alike. I never noticed the difference until today, but like I said I notice that the shorter style guides are in several earlier 16” Chinese AK’s as well, while basically every other gun I looked at has a guides similar to the NHM-91 style. That MAK-90 short guide had a large gap for the round to jump before hitting the ramp. Not sure what to make of all that, still think I will need to just chamfer that edge to make it feed better, but it is weird finding the differences in bullet guide styles. |
a loaded gun won’t set you free, so you say…
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First there's one test that's free.. Over the years I've seen some people have FTF issues with weak recoil springs. You could swap with another AK and try it out. I'd be careful working the bullet guide on the MAK90 since it's part of the trunnion and can't be replaced like on other AKs I'm more curious if the selector stop plate at the mag catch is too thin. You might compare the one in the NHM91 to the one on the MAK90 There's also some dimensional drawings out there that you could use to determine if the selector stop is too thin. 
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Originally Posted By mancat: I'd be careful working the bullet guide on the MAK90 since it's part of the trunnion and can't be replaced like on other AKs Originally Posted By mancat: I'd be careful working the bullet guide on the MAK90 since it's part of the trunnion and can't be replaced like on other AKs They use a standard bullet guide like other AKs. The rivet is generally extremely well blended making it look like it's one piece. ETA: turns out they do have a single-piece trunnion. I couldhave sworn that I've replaced the BG on stamped T56 at one point. But maybe not. Originally Posted By mancat: I'm more curious if the selector stop plate at the mag catch is too thin. You might compare the one in the NHM91 to the one on the MAK90 There's also some dimensional drawings out there that you could use to determine if the selector stop is too thin. https://i.imgur.com/FdbtmXM.png Agreed. This is generally the first check I do when an AK is having these issues. Another quick check is too see if the top of mag feed lips are touching the underside of the rails. If they're not, likely the selector stop plate is too thin or the mag catch lug it's too thin. |
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Originally Posted By AEnemaBay: They use a standard bullet guide like other AKs. The rivet is generally extremely well blended making it look like it's one piece. Agreed. This is generally the first check I do when an AK is having these issues. Another quick check is too see if the top of mag feed lips are touching the underside of the rails. If they're not, likely the selector stop plate is too thin or the mag catch lug it's too thin. Originally Posted By AEnemaBay: Originally Posted By mancat: I'd be careful working the bullet guide on the MAK90 since it's part of the trunnion and can't be replaced like on other AKs They use a standard bullet guide like other AKs. The rivet is generally extremely well blended making it look like it's one piece. Originally Posted By mancat: I'm more curious if the selector stop plate at the mag catch is too thin. You might compare the one in the NHM91 to the one on the MAK90 There's also some dimensional drawings out there that you could use to determine if the selector stop is too thin. https://i.imgur.com/FdbtmXM.png Agreed. This is generally the first check I do when an AK is having these issues. Another quick check is too see if the top of mag feed lips are touching the underside of the rails. If they're not, likely the selector stop plate is too thin or the mag catch lug it's too thin. TIL... I thought the MAK90 trunnion was milled as a single piece |
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Always start trouble shooting with the simple stuff first. Try a sample of mags first. I'm betting its a mag issue be it feed lips,mag springs,fitment etc. Next could be ammo but I doubt it. Recoil spring is possible. |
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Originally Posted By CarlosC: OP, I also have a MAK-90 and took a look at mine because, at first, your guide looked like it was chipped to me. However, your guide and mine are identical, including the gap to the magazine. Same, just pulled mine out of the safe and looks identical. FWIW OP I only have Pmags and they feed wonderfully both FMJ and HP |
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In theory, any 7.62x39 AK mag will work. In reality, they don't. It's very common to have to file down mags from a different country. Find mags that work (start with Chinese ones) and then modify the Euro mags. Always modify the cheap part, not the gun, if you can help it. Especially, if the rifle is no longer importable. |
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Originally Posted By Gotterdammerung: In theory, any 7.62x39 AK mag will work. In reality, they don't. It's very common to have to file down mags from a different country. Find mags that work (start with Chinese ones) and then modify the Euro mags. Always modify the cheap part, not the gun, if you can help it. Especially, if the rifle is no longer importable. Good advice here. |
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Shooting and Reloading, one hobby feeds the other.
Shooting and Reloading, one hobby feeds the other.
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Originally Posted By Gotterdammerung: In theory, any 7.62x39 AK mag will work. In reality, they don't. It's very common to have to file down mags from a different country. Find mags that work (start with Chinese ones) and then modify the Euro mags. Always modify the cheap part, not the gun, if you can help it. Especially, if the rifle is no longer importable. Interesting. For some reason, I've always used matching mags with my AKs by country, which makes it a chore going to the range, but I've also I've never had any feeding problems. But, based on what you said, I decided to check feeding angles using different country's mags with just my MAK and I did see the feed geometry is slightly different among them. They all still fed, but the Romy mags fed least directly, while the Russian bakelite and Bulgarian plastic fed most directly into the chamber. |
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Originally Posted By Gotterdammerung: In theory, any 7.62x39 AK mag will work. In reality, they don't. It's very common to have to file down mags from a different country. Find mags that work (start with Chinese ones) and then modify the Euro mags. Always modify the cheap part, not the gun, if you can help it. Especially, if the rifle is no longer importable. Kind of disagree, though that is a good method for a one off firearm that is having issues. However my preference is to make sure both parts are within correct specs, and because I own a lot of AK’s and a lot of mags, they all need to work well together. Don’t think it is the mags at all here at all either. Same mag sits a round at the same height from the bolt rail in multiple chinese AK’s using digital micrometer. What I do see is that the problem gun’s bullet guide has an extremely squared edge- zero chamfering to it, unlike my others which range from some rounding to a nicely done radius on a Poly. So I think that is why they work and it doesn’t. For mags- My preferred method if a mag doesn’t seat is to check the rifle with multiple (10 or more) surplus steel mags, and if several of them have issues locking in, to file the mag catch slightly, sometimes just smoothing the edge helps a lot. But typically this happens more when building up a kit onto a new receiver vs dealing with a factory built rifle. I have modified the catch height surface on a mag before, when it clearly was the problem, but that hasn’t been often with actual surplus mags. Side note- some or all NHM-91 rifles also had a raised rivet on the mag catch to keep regular mags from seating, so that needed to be machined out/dremeled before you could ever seat a larger mag. The 5 or 10 rd mags that came with the NHM series had a slot cut in them for that reason. |
a loaded gun won’t set you free, so you say…
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Originally Posted By plinker8: Same, just pulled mine out of the safe and looks identical. FWIW OP I only have Pmags and they feed wonderfully both FMJ and HP Originally Posted By plinker8: Originally Posted By CarlosC: OP, I also have a MAK-90 and took a look at mine because, at first, your guide looked like it was chipped to me. However, your guide and mine are identical, including the gap to the magazine. Same, just pulled mine out of the safe and looks identical. FWIW OP I only have Pmags and they feed wonderfully both FMJ and HP Yeah I was quite surprised to see ‘94 Mak-90’s with a shorter guide, while the ‘92 and ‘93 NHM’s had a “normal” longer guide. The others I found with short style guides were a Norinco 56S and a Polytech AKS-762 Spiker. As both of these predated the 1989 ban and are pretty valuable I have not shot them much beyond testing and making sure they were zeroed, but they did work fine. Both guides do have the edge chamfered though. Meanwhile I checked another MAK-90 from a parts kit. No idea why it was originally cut up, but the “MAK-90” markings on it appear hand stamped, pretty poorly done, with no year marking, so it possibly was originally a different named model and was made into a “MAK-90” later. Anyhow this one had the longer style bullet guide… 56S: Attached File Poly Spiker: Attached File My “helper” who was sneaking into the picture: Attached File |
a loaded gun won’t set you free, so you say…
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Originally Posted By CarlosC: Interesting. For some reason, I've always used matching mags with my AKs by country, which makes it a chore going to the range, but I've also I've never had any feeding problems. But, based on what you said, I decided to check feeding angles using different country's mags with just my MAK and I did see the feed geometry is slightly different among them. They all still fed, but the Romy mags fed least directly, while the Russian bakelite and Bulgarian plastic fed most directly into the chamber. I have a few boxes of AK “range mags” that I use with all of them. Had to go thru them a while back, left most of the chinese flatback mags in there, but took out a few Polytech ones…. |
a loaded gun won’t set you free, so you say…
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Originally Posted By AEnemaBay: They use a standard bullet guide like other AKs. The rivet is generally extremely well blended making it look like it's one piece. Agreed. This is generally the first check I do when an AK is having these issues. Another quick check is too see if the top of mag feed lips are touching the underside of the rails. If they're not, likely the selector stop plate is too thin or the mag catch lug it's too thin. Originally Posted By AEnemaBay: Originally Posted By mancat: I'd be careful working the bullet guide on the MAK90 since it's part of the trunnion and can't be replaced like on other AKs They use a standard bullet guide like other AKs. The rivet is generally extremely well blended making it look like it's one piece. Originally Posted By mancat: I'm more curious if the selector stop plate at the mag catch is too thin. You might compare the one in the NHM91 to the one on the MAK90 There's also some dimensional drawings out there that you could use to determine if the selector stop is too thin. https://i.imgur.com/FdbtmXM.png Agreed. This is generally the first check I do when an AK is having these issues. Another quick check is too see if the top of mag feed lips are touching the underside of the rails. If they're not, likely the selector stop plate is too thin or the mag catch lug it's too thin. So I checked the height of a round (measured where the projectile meets the casing, at TDC) to the bolt rails, and the problem gun was pretty much the same as all the others. So it isn’t putting the cartridges up too high or too low. Pretty sure it is the fact that the problem gun has a sharp corner on the bullet guide while the rest have been rounded. |
a loaded gun won’t set you free, so you say…
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Have tested it out on a couple range trips, after applying a file and then emery cloth to the sharp feed ramp edge. Made a huge difference and it works fine now. Gun also had minimal wear so a bit of wearing in has not hurt either. Just need to figure out why it groups kind of crummy with Golden Tiger FMJ… In the testing process I did find a problem AK mag, not one I had used initially in this rifle though. The problem mag (Euro) had some flashing on the inside from the spot welds, so it would hang up the folower occasionally. I had to file down the weld flash and that fixed it, but then I also went thru every single mag in my AK range mag boxes and serious use AK mag boxes to make sure no other mags had that issue- none did. First time I have seen it in an AK mag before, have had to deal with a couple cases of AR mags though in the past with a similar issue- they were easier to fix since they were aluminum and a big flat blade screwdriver broke off the flash, but what a pain those were. |
a loaded gun won’t set you free, so you say…
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Originally Posted By mancat: First there's one test that's free.. Over the years I've seen some people have FTF issues with weak recoil springs. You could swap with another AK and try it out. I'd be careful working the bullet guide on the MAK90 since it's part of the trunnion and can't be replaced like on other AKs I'm more curious if the selector stop plate at the mag catch is too thin. You might compare the one in the NHM91 to the one on the MAK90 There's also some dimensional drawings out there that you could use to determine if the selector stop is too thin. https://i.imgur.com/FdbtmXM.png I would caution about using online drawing info to draw too many conclusions from. Working on a F/A conversion with another SOT and the info from a well known manual is clearly not accurate on one thing I looked at. Plus I reverse engineered the AK receiver about 20 years ago, and found then that a lot of the online drawings were way off. So if it is online, I would not trust it, but it is a good starting place. |
a loaded gun won’t set you free, so you say…
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