View Full Version : The AK-74M
As a result of 10 years combat experience in Afghanistan (1979-1989), the Soviets decided to make a few tweaks to the AK-74. From what I've read from various sources, the familiar laminated wood didn't hold up all that well in sustained operations so they went to synthetic furniture.
From what I gather, AK-74's were finished in standard bluing during most of the conflict. This was changed to whatever the current finish is (paint over Parkerization?).
The mags went from the original (or at least very common) orange Bakelite-type color to a flat black.
I believe the muzzle brakes went through various small changes over the years.
All this resulted in the AK-74M which was introduced around 1991 or thereabouts.. For those more familiar than me, were there any changes to the internals as a result of combat experience?
Good question. LAV might chime in here as he's the encyclopedia on a lot of this kind of thing. I have read that they changed the receiver composition to a different and more durable steel for the modern Russian rifles. Haven't seen exactly what that material is, but supposedly it's different from previous versions. Also, the sidefolding stocks were changed to a 5.5mm pin from the more common 4mm. The rear trunnions had to change as well to accommodate this, as well as a slight angle change to the stock to make it more of a straight line. When building a rifle with the modern Russian rear trunnions, you'll notice that the Bulgarian and earlier Russian trunnions are machined at a slightly different, and will not fit right on receivers modeled after the Bulgarian / early Russian versions. I'm assuming (could be wrong) that this was done to increase the strength of the mechanism and perhaps to aid in recoil management. Gas blocks and fsb's are pressed on and dimpled to the barrel vs. being pinned on the newest ones as well. I'm sure other improvements were made as well.
Minor correction: After some research it seems that 1985 was the last year for laminated wood furniture on production AK-74's. That year began the transition to synthetic furniture, although this may have been the plum-colored variety.
I would have thought it was much later.
I know they went from a AKM style 45 degree gas block to a 90 degree version.
I'm glad my first post after being a long-term lurker is about something I'm knowledgeable about, and not asking some dumb question.
Source for all of the following: Memory. ~10+ years of casual, yet detailed, research on the AK platform. Several books and websites. I also have an SGL-31-94 which is for all intents and purposes an AK-103 internally. See note above checklist.
Were there any changes to the internals as a result of combat experience?
Changes from the AK-74 to the AK-74M include (but are not limited to):
(All of these changes are also reflected in the AK-100 series, since they are essentially AK-74Ms in different calibers and barrel lengths.)
1. Updated muzzle device (still the 74-brake, just refined)
2. New black bayonet (think the Circle-10 ones that K-var sells)
3. Front sight and gas block DIMPLED on instead of pinned (look at Saigas in their imported form, they have it)
4. Standardized black polymer handguards, pistol grip and magazines
5. Standardized side-mounted optic rail (eliminated need for the AK-74N)
6. Standardized folding stocks (eliminated need for the AKS-74)
7. Changed rear trunnion angle and pin size from 4.5mm to 5.5mm (the Bulgarians [like the SLR-106 and SLR-107] still use the 4.5mm pins and old trunnion angle)
8. Folding stock standardized as a plastic stock that emulates the fixed polymer stock of later AK-74 models, instead of the AKS-74 steel triangle folder.
9. Flat top cover instead of ribbed.
10. Changes to bolt, bolt carrier, and gas piston. The AK-74 uses a smaller, lighter bolt than the AKM, and the carrier changed to accommodate the smaller bolt (same size carrier, but with a smaller hole). The AK-74M further refined the bolt and carrier, (I forget exactly how) and uses a smooth (not grooved) piston head, and the piston attaches to the carrier differently (I forget exactly how.)
ETA: 11. A rivet was added to the left side of the receiver to facilitate bolt turning.
To illustrate these changes, take apart a factory Saiga (5.45/7.62/5.56) or SGL-21 or -31 series rifle, and compare the bolt, carrier, and piston to a Bulgarian SLR-106/107
The Bulgarians still use AKM-pattern internals for their SLR-106 and 106, (the SLR-105 in 5.45 uses AK-74 style internals, but not the newer 74M internals) as well as their own military rifles. In fact, Russia is really the only ones who use the AK-74M/AK-100 internals in their guns.
Minor correction: After some research it seems that 1985 was the last year for laminated wood furniture on production AK-74's. That year began the transition to synthetic furniture, although this may have been the plum-colored variety.
I would have thought it was much later.
Yes, the AK-74 transitioned from mostly laminate furniture and bakelite magazines to plastic furniture and magazines from the mid 1980s until the AK-74M standardized the black plastic.
I know they went from a AKM style 45 degree gas block to a 90 degree version.
This change occurred during the transition from the early AK-74 to the current (post-1977) version (thank you SteyrAUG and MadAngler1), but not from the AK-74 to the AK-74M. They found the 45-degree gas block sheared (TY MadAngler 1) the super-fast 5.45mm bullet and the 90-degree fixed it. The Romanians kept the 45-degree angle in their 74-variants, however (example: gas blocks on SAR/WASR-2)
The 45-degree gas block on the AK-74 apparently caused a phenomenon called "bullet shear", although I'm not sure how or why.
This change occurred during the transition from the prototype AK-74 to the production version. They found the 45-degree gas block deformed the super-fast 5.45mm bullet (I forget exactly how) and the 90-degree fixed it. The Romanians kept the 45-degree angle in their 74-variants, however (example: gas blocks on SAR/WASR-2)
I'll have to look but I'm almost positive I have pics of Afghans in the early 80s with 74s that have 45 degree gas blocks.
MadAngler1
10-21-13, 18:19
I'll have to look but I'm almost positive I have pics of Afghans in the early 80s with 74s that have 45 degree gas blocks.
You are correct. The 45 degree gas block was first carried over from the AKM to the AK-74. They wound up drilling into the lands of the barrel (not just the grooves) in making the gas ports, resulting in bullet shear due to the high pressure and high velocity of the 5.45 x 39 cartridge (as opposed to 7.62x39 rounds). The 90 degree gas block lessens the liklihood of this problem found in the 5.45 AK-74, and again, the port is supposed to be drilled into the groove of the barrel.
Check out Frank Iannamico's AK-47: The Grim Reaper, page 102. AK-74s made after 1977 implemented the 90 degree gas block. Romanian AIMS-74 rifles (imported to the states as the SAR-2, and I own one of these fine rifles) possess 45 degree gas blocks. I get roughly 2-3 MOA with my gun with Barnual FMJ or JHP ammo, and I can easily hit wild pig sized targets at 200 yards with the gun. Hitting an 8 inch circle with irons at 100 yards is no problem.
I read somewhere that the burnt-orange colored mags didn't help in concealment and so later mags went to plum/flat black. Was that actually the case?
Sorry I don't have these built yet, but here are a couple of 1980's Russian AK74 kits.
1983:
http://imageshack.us/a/img33/9500/4g7h.jpg
1988:
http://imageshack.us/a/img541/2533/k6oe.jpg
I'll have to look but I'm almost positive I have pics of Afghans in the early 80s with 74s that have 45 degree gas blocks.
You are correct. The 45 degree gas block was first carried over from the AKM to the AK-74. They wound up drilling into the lands of the barrel (not just the grooves) in making the gas ports, resulting in bullet shear due to the high pressure and high velocity of the 5.45 x 39 cartridge (as opposed to 7.62x39 rounds). The 90 degree gas block lessens the liklihood of this problem found in the 5.45 AK-74, and again, the port is supposed to be drilled into the groove of the barrel.
Check out Frank Iannamico's AK-47: The Grim Reaper, page 102. AK-74s made after 1977 implemented the 90 degree gas block.
You guys are absolutely right and I've changed my post to reflect that (and a few other changes.) Now that I'm home, I opened my own copy of AK-47: The Grim Reaper (fantastic book) which confirms it and along with crediting the both of you, have made other small changes after perusing the book again.
I was also (and had a feeling that I was) wrong about the AK-74 using an AKM bolt. The -74 bolt is indeed smaller and the carrier has a smaller hole to match. My post should hopefully be far more correct.
Heavy Metal
10-22-13, 19:53
You are correct. The 45 degree gas block was first carried over from the AKM to the AK-74. They wound up drilling into the lands of the barrel (not just the grooves) in making the gas ports, resulting in bullet shear due to the high pressure and high velocity of the 5.45 x 39 cartridge (as opposed to 7.62x39 rounds). The 90 degree gas block lessens the liklihood of this problem found in the 5.45 AK-74, and again, the port is supposed to be drilled into the groove of the barrel.
Check out Frank Iannamico's AK-47: The Grim Reaper, page 102. AK-74s made after 1977 implemented the 90 degree gas block. Romanian AIMS-74 rifles (imported to the states as the SAR-2, and I own one of these fine rifles) possess 45 degree gas blocks. I get roughly 2-3 MOA with my gun with Barnual FMJ or JHP ammo, and I can easily hit wild pig sized targets at 200 yards with the gun. Hitting an 8 inch circle with irons at 100 yards is no problem.
The Romanina gas block is 45 degrees but the gas port itself is tangential to the bore. The came upon a simpler solution to the problem.
Heavy Metal
10-22-13, 19:55
From what I gather, AK-74's were finished in standard bluing during most of the conflict. This was changed to whatever the current finish is (paint over Parkerization?).
The Sovs switched to paint over phposphate for most of their small arms in the 50s. The Soviet AK-74 was never blued. I don't think the AKM was ever blued either, not by the Soviets.
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