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Happy Camper
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... I'm compiling some information on my website about accurizing the AK. I am doing most of it from memory and want another set of eyes to look it over before I post something really stupid.

Here's what I have so far... I'd like to know if something doesn't sound OK or is questionable:


Most all of these are minor components, but can accumulate into a noticeable change of behavior in the rifle.

  1. It almost goes without saying that quality ammunition can perform better than "plinking" ammunition. Match-grade ammunition is almost non-existent for AK rifles, but good quality ammunition is available. Once you find a good brand of ammunition, you should stick with it, but not assume that each lot will yield identical results.
  2. Tight Headspace yields better consistency over time. The AK design will inherently make headspace "loosen up" after a few thousand rounds, so tighter headspace is better.
  3. The lower hand guard should fit slightly loose, with a minor amount of front-to-back looseness. This minimizes the lateral barrel tension.
  4. Ditto for the gas tube - there should be some minor looseness during installation. This affects the barrel tension, which will directly affect barrel whip and can aid grouping.
  5. Ditto again for bolt-on accessories such as bipods, front hand grips, etc. A "free float" design can't be achieved on an AK, but the less that is touching the barrel the better.
  6. Piston length can be adjusted to allow more time to pass before the action cycles. This affects recoil forces before the bullet completely exits the barrel. Longer time is preferred.
  7. The bolt face and mating surfaces should be lapped with very, very fine lapping compounds to provide a better mating surface between the bolt and trunion.
  8. A good barrel crown will ensure uniform dispersion of the gases at the instant the bullet leaves the barrel. Inconsistent barrel crown can cause those gases to exit in a less predictable manner. Target crowns can be 90-degrees perpendicular to the barrel, and some crowns have a recessed "cup" to further influence the gas dispersion.
  9. The barrel cleaning should be performed with a slip-on attachment or from the breech end to ensure the barrel cleaning rod does not scrape the crown.
  10. Muzzle attachments can further reduce the uniform dispersion of exhaust gasses and should therefore be removed.
  11. Barrel length can directly affect groupings. When firing, barrel will oscillate or "whip" in response to the normal forces exerted during the firing cycle. Factors such as the bullet dimensions, powder charge, rifling speed, etc. will all influence the amount of oscillation the barrel endures. The optimal barrel length is that which the bullet is at the "zero" position during the oscillation cycle. Shortening a barrel could cause the bullet to exit when the barrel is not at the "zero" position. This will most directly affect point of impact and could require re-zeroing the rifle.
  12. The harmonics of barrel whip will be improved by a heavy (bull) barrel and fluted barrels.
  13. Heat will also affect barrel zero, and therefore the first shot is considered the "cold shot". Subsequent shots will probably drift away from the first shot point of impact. Again, heavy and fluted barrels will improve performance.
  14. Cryogenic barrel treatment rearranges the molecular characteristics of the barrel, causing the metal to behave in a more consistent and reliable manner. The result is a barrel that produces tighter groups.
 

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Some random comments...

"Tight Headspace yields better consistency over time. The AK design will inherently make headspace "loosen up" after a few thousand rounds, so tighter headspace is better."

Tight headspace has its drawbacks, too. It's common among SAR-3's, and mine is an example: The bolt won't quite close on a 5.56 "GO" gauge. Tight headspace can result in your weapon failing to fire because the bolt won't go into battery, in a worst-scene scenatio the weapon fires without the bolt in battery. I'm sticking with steel-cased ammo in my SAR-3 'til the bolt lugs wear down a bit and the headspace becomes normalized.

"The lower hand guard should fit slightly loose, with a minor amount of front-to-back looseness. This minimizes the lateral barrel tension.
"Ditto for the gas tube - there should be some minor looseness during installation. This affects the barrel tension, which will directly affect barrel whip and can aid grouping."

I don't know that this would have enough effect to improve barrel harmonics.

"Ditto again for bolt-on accessories such as bipods, front hand grips, etc. A "free float" design can't be achieved on an AK, but the less that is touching the barrel the better."

Barrel-mounted accessories shouldn't be loosely mounted, they shouldn't be mounted at all if accuracy is important to you. No need to make a bad situation worse.

"Piston length can be adjusted to allow more time to pass before the action cycles. This affects recoil forces before the bullet completely exits the barrel. Longer time is preferred."

I rather suspect that the bullet has left the muzzle before any sort of cycling of the action begins, anyway.

"The bolt face and mating surfaces should be lapped with very, very fine lapping compounds to provide a better mating surface between the bolt and trunion."

I'd never heard of this. I should think that the mating surface between the bolt and trunion is at the locking lugs. And lapping them will result in increased headspace.

"A good barrel crown will ensure uniform dispersion of the gases at the instant the bullet leaves the barrel. Inconsistent barrel crown can cause those gases to exit in a less predictable manner. Target crowns can be 90-degrees perpendicular to the barrel, and some crowns have a recessed "cup" to further influence the gas dispersion."

I've seen it reported at Brand X where folks have reported exceptional improvments in accuracy by having the muzzle re-crowned. Seems to be mostly an issue among SAR's, with their sloppy quality-assurance standards.

"The barrel cleaning should be performed with a slip-on attachment or from the breech end to ensure the barrel cleaning rod does not scrape the crown."

The design of the AK is such that it's pretty near impossible to clean from the breech. I use a pull-through.

"Muzzle attachments can further reduce the uniform dispersion of exhaust gasses and should therefore be removed."

I think this may be an issue only with poorly-installed, i.e. uncentered, muzzle attachments. A properly-installed muzzle attachment will likely change your zero, but once you've sighted in again I doubt that it would be a problem.

"Barrel length can directly affect groupings. When firing, barrel will oscillate or "whip" in response to the normal forces exerted during the firing cycle. Factors such as the bullet dimensions, powder charge, rifling speed, etc. will all influence the amount of oscillation the barrel endures. The optimal barrel length is that which the bullet is at the "zero" position during the oscillation cycle. Shortening a barrel could cause the bullet to exit when the barrel is not at the "zero" position. This will most directly affect point of impact and could require re-zeroing the rifle."

Well, the AK is already at minimum length unless you want to fuss with registration of a SBR with BATFE.

"The harmonics of barrel whip will be improved by a heavy (bull) barrel and fluted barrels.
"Heat will also affect barrel zero, and therefore the first shot is considered the "cold shot". Subsequent shots will probably drift away from the first shot point of impact. Again, heavy and fluted barrels will improve performance."

Sorta go together for we SAR-3 owners. The SAR-3 barrel is pretty skinny, so it heats up rapidly and shots begin to string. Given the difficulty-to-impossibility of installing a fluted or bull barrel, quickest solution is to simply slow down your rate of fire.

"Cryogenic barrel treatment rearranges the molecular characteristics of the barrel, causing the metal to behave in a more consistent and reliable manner. The result is a barrel that produces tighter groups."

I've heard this helps, too, but I've never seen it verified with a before-and-after report.


Seems to me that one of the most important things got left out - caliber. I've got a 5.56 AK, and by most reports that seems to be the most accurate caliber for an AK, with 5.45 next, and 7.62 third.

Perhaps one of the greatest impediments to accuracy with an AK is its abyssmal sights: Open rear sight and round-post front, arguably the least accurate sighting system ever designed. A flat-faced front sight can be obtained by installing an ACE sight drum that allows use of AR front sights, or, for the more maniacal, a flat-faced front sight can be custom installed (I've got a Williams' Fire Sight front sight for an SKS installed in mine). The rear sight is much more problematic, since it is difficult-to-impossible to solidly mount a receiver sight (i.e. a peep sight mounted at the rear of the receiver where it belongs) on an AK. This Gordian knot can be cut by getting optics.

The trigger of the AK is typically abyssmal, and that of SAR's is simply junk. If accuracy is a prime consideration for you, it's worth your while to invest in a Red Star Arms fire-control group for your AK, although many would contend that a target-grade adjustable trigger for an AK is absurd.

While it is (at least for me) numbingly boring and tedious, take the time to sight your weapon in properly.

The best way to improve accuracy with any weapon is to read (or re-read) a basic text on shooting positions and then shoot a lot.
 

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Any muzzle device (Brake) that fits loose is going to be bad for accuracy. I was just handling my '74 and was thinking of this. Accurized M1's and M14's had stuff snug or even tight! A loose flash hider on a '14 was a sure cause of poor accuracy. I was SOP to glue the upper handguard to the front band.

I think if you really want to experiment with an accurate AK, I would first try to disable the gas system and start from there, as a single shot rifle and then try to secure the stuff hanging off the barrel, see if some of the things we did in the past to our US service rifle's would be able to be applied to the AK. As a platform, I think the AK74 would be better than the '47. Little bullets tend to make little groups.
 

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I've been doing some thinking on this subject as well.....and I have some theories.
I agree, we have way too much stuff hung on the too-thin barrel. This is going to be our biggest hurdle. The AK was NOT designed to be especially accurate-it's designed to be reliable. This means a fair amount of slop in tolerances which will lead to lesser accuracy. Also, we have a stamped sheet metal receiver, which will give us some flex, which is going to increase whip. It's nearly impossible to create a truly accurate rifle based on the AKM. However, the best things we can do is correct the barrel crowns, shoot decent ammo when accuracy counts, and put a useable 4X scope or red dot sight on, as the sights well and truly suck.
 

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I was told that case/bolt fit should be as consistent as possible. I can see how this might be logical, but as long as the bolt is locked... Hmm. The same guy who told me that, went to the trouble of lapping his Mauser barrel to make even contact with shoulders in the receiver. He lapped the locking lugs for even contact. He also used some jig (copied from a commercially made one) to lap the bolt face so it was perpendicular to the bore of the barrel. I have to say that it did make for a NICE accurate and consistent rifle. I didn't shoot badly at all with it, but he shot single hole groups with it. Hmm.

So what about the fit between bolt and carrier? I just chambered a 5.45 dummy in one of my parts kits and there is still a noticeable amount of movement even with the bolt locked. I would imagine the hammer would easily put enough pressure on the bolt to rock it during firing.

If you decrease the slop between the bolt and carrier, I think that might decrease the reliability that's built into the AK design.

Maybe start with a threaded milled receiver. Go with a 21" 7.62 blank, turn a target profile on it, and an 11 degree crown. Make a custom gas block and don't install a Front Sight Block. Use a standard sight rail and weld or braze it to the receiver. Use decent optics. Free float the handguard. Lap the bolt lugs. Reduce the play between the bolt and carrier, and see what it does.

EDIT: Almost forgot. POST PICS OF IT WHEN FINISHED!!!
 

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If you're going to build a weapon from the ground up, including a custom barrel, seems to me you could also consider expanding your range of calibers beyond 5.45. 5.56, or 7.62 and maybe look into some others that have greater inherent accuracy but could still be used in a perhaps-modified AKM or AK-74 mag.

As soon as someone makes a receiver sight that attaches via the optical rail of the AK, I'm buying one. I think there'd be a good market.
 

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"Muzzle attachments can further reduce the uniform dispersion of exhaust gasses and should therefore be removed."

Myth. I have AKs with and without these - they have zero effect.

"Cryogenic barrel treatment rearranges the molecular characteristics of the barrel, causing the metal to behave in a more consistent and reliable manner. The result is a barrel that produces tighter groups"

Possible Myth - my cryo'ed 223 is no better than my non-cryo'ed 223.

Something to add....

Install the gas piston as tight as you can - NO slop.

On my builds? Doing this has resulted in consistantly better performance.
 

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Yeah, I've always kind of wondered about the muzzle device thing-the bullet is already past it when the gasses are coming out behind it. This is a big thing with the AR crowd, and never fully made sense to me-once the bullet has exited the barrel past the crown, it's on it's way without assitance from the gases, which go outwards.
I've heard from folks that cryo does indeed help accuracy, in certain types of firearms, especially very high accuracy arms-benchrest guns, accurized olympic competition .22's, "free" pistols and the like. I don't think the AK system would benefit from it though, as there is too much working against it.
I think the typical crappy accuracy comes from the fact most AK guys use junk ammo-Wolf, Uly, surplus, whatever's cheapest really.
And those awful sights. Wow, could they be worse? Too far away, indistinct, frequently canted off to one side or the other, and that difficult to index front post in rear notch, both of which are TOO SMALL. I put east german night sights on my AK's-not for night shooting, but because they are bigger.
 
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