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Old July 11, 2011, 09:28 AM   #1
chewie146
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AR-15 7.62X39 Synopsis/Questions

Hey all,

A friend of mine just got an AR in the good ole 7.62X39. What issues have you faced with this, and does the AR handle steel cased ammo, light strike possibilities aside?

Thanks
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Old July 11, 2011, 12:00 PM   #2
DnPRK
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The big issue is lack of suitable standard capacity magazines for 7.62x39. You can get magazines designed for other cartridges to work if you load no more than 10 rounds. More than 10 rounds can cause feeding problems due to highly tapered cartridges and lack of curvature in the magazine.
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Old July 11, 2011, 01:33 PM   #3
wnycollector
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The best mags on the market currently are made by ASC (the former C-products) Here is link http://www.ammosc.com/storename/ammu...pt-273398.aspx

Light primer strikes can be dealt with in two ways: a Model1 sales 7.62x39 firing pin or a AR performance super bolt. Here are links to both:
http://www.model1sales.com/index.cfm...ategory_id=421
http://www.ar15performance.com/inc/sdetail/3255/3761
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Old July 11, 2011, 02:02 PM   #4
tAKticool
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Something I liked the initial glance but so expensive and what really is the general point -- 7.62x39 doesn't take an AR. I'd rather really rather the Savage scout rifle wth GRS, forewars scout scope mout and bolt action.
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Old July 11, 2011, 08:26 PM   #5
HankC1
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Quote:
The best mags on the market currently are made by ASC (the former C-products) Here is link http://www.ammosc.com/storename/ammu...pt-273398.aspx

Light primer strikes can be dealt with in two ways: a Model1 sales 7.62x39 firing pin or a AR performance super bolt. Here are links to both:
http://www.model1sales.com/index.cfm...ategory_id=421
http://www.ar15performance.com/inc/sdetail/3255/3761
The remaining issue is bolt head breakage due to larger case diameter resulting in not enough material left on bolt head around the case. Wish it is fixed too.
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Old July 11, 2011, 09:11 PM   #6
Mobuck
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I haven't shot a lot of ammo through my Colt 7.62 upper but enough to have some opinions. My first mags were plastic and don't activate the bolt hold open consistently. Then I got C-Products and have no problems with those. My rifle functions with steel case ammo but is much more accurate with good quality handloads using the correct diameter bullets. A 16" barrel with open sights is not a good platform for accuracy testing so I used a carry handle mounted scope for that.
If you have concerns about the bolt, just keep a spare. Breaking one lug off doesn't usually create a big safety issue or so I'm told.
The only reason I got the 7.62 upper was because it was cheaper than an AK at the time. I had an AK and didn't care for the controls, accuracy, or the hassle required to mount a scope--none of which are a problem with the AR.
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Old July 11, 2011, 10:45 PM   #7
EdInk
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The workhorse cartridge of the Warsaw Pact and the AR platform just don't seem to get along well.
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Old July 12, 2011, 08:21 AM   #8
tirod
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If the 7.62x39 has it's sweet spot, it's in a Kalishnikov designed magazine. The two were made for each other, and a high point in how to do it right. The magazine itself is extremely durable, and since it's so hard to get out of whack, it always presents ammo to the AK bolt at the right angle, with no mag well to complicate it. The complete lack of malfunctions gives the gun it's reputation. It's not the action, its that magazine.

The AR doesn't use it, and doesn't even accomodate a curved mag. It was designed for a straight 20 rounder, and even the later 30 round mags are typically underbuilt, prone to damage, require antitilt followers, and get a curved action to them by enforcing a short overall length. Spring pressures are high, requiring you to either download the mag to 28, or suffer malfunction getting the first shots off.

Some bright boy decided to marry the x39 to the AR action, and that means a head on collision with a tapered case cartridge feeding into a straight mag well. Take a long look at what passes for a magazine for this crossbreed - they're called frankenmags for a reason. Ones that feed dead nuts reliably - enough to trust you life to - are few and far between.

Some people need an example of why something shouldn't be done, and in firearms, this is it.
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Old July 12, 2011, 08:52 AM   #9
doofus47
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My history with a 7.62 upper
Issue 1: getting dependable mags. Cproducts resolved this issue. I have 5,10,25 (officially 30) round mags and they all work fine.
Issue 2: FTF. I upped the hammer spring tension to give it more power and this problem went 95% away. Generally, if a round FTFs, it isn't going to go off with a second or third strike. This is good enough for plinking. Other people buy/make firing pins that strike a little deeper. This would have been my second choice if I still had issues. It's a cheap mod and I wouldn't have balked at it since you are forcing the AR to fire ammo that it wasn't designed for.
Issue 3: finding ammo.... I love shooting it. It might have retired my SKS.

happy shooting.
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Old July 14, 2011, 05:19 PM   #10
RC20
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Robinson Arms XCR is MADE for that caliber (its multi caliber, but the 7.62 was one it was designed for and around).

Actually the XCR is a fully modernized AK, except its accurate and well done. Controls make the AR setup look and feel like the junk they are (yes I hate them and I am getting one because I want a tack driver).

Best standard trigger (new ones, older ones have a poor trigger) other than RRA two stage match trigger (yes I have used both or all three as I got an older XCR and upgraded the trigger).

Caveat: Its a hard hitter on primers, the primers look like thy are about to blow, but its typical of the XCR. Hope they fix that, but they sure as hell nail the primer, you will not get light strikes with the XCR!)..

Customer servcie can suck, about 20% seem to have some problme with the gun. If you ever go that route, then use Danny as your point of contact and he will do a good job for you.

Go to the XCR forum, good unbiased take on Robinson Arms. Basically we like the gun, hate Alex for his attitude and not taking an excellent product and company and what could be an outstanding design to the next level (he needs to turn management over to a professional and work on gun design and improves as he is damned good at that)

The ergonomics of the gun beat anything out there including the ACR and SCAR-L and the basic gun is terrific. They are not keeping up with coatings and things like rail markings.
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Old July 16, 2011, 11:06 AM   #11
tirod
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I don't believe the XCR was mentioned by the OP. But, thanks for adding in what we needed to know.

20% failure rate? Poor customer service? Not as accurate as the AR15? And after 45 years of tested combat use, the AR controls feel like junk, but the XCR has better ones?

Well, they got one out of three - which makes sense, the XCR has to sell to civilians, the AR designers were selling to professional military users. The perceived feel of the controls vs. economical best bid on govern't contract - gotta make a choice. Soldiers got reliable function, not so much "feel good."

Fit and finish is for customers with discretionary income who want to impress others. Combat is for users who need it to work right no matter what. I'll take the one with a 45 year history of getting it more right.
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Old July 16, 2011, 02:01 PM   #12
tobnpr
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Old July 31, 2011, 11:19 PM   #13
chewie146
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Well we tried the little Armalite, and it's a really neat little gun. Not a single malfunction that wasn't magazine related, and that was the 1, 10-round mag that came with the gun. It was of unknown manufacture. The other 3 magazines are Armalite made, and all functioned flawlessly with a variety of ammo, including PMC, Remington, and Silver Bear.
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Old August 1, 2011, 06:52 AM   #14
Lloyd Smale
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ive got a bushmaster and its gone through 3 cases of wolf and i dont know how many reloads and its been very reliable. I did switch to c products mags and replaced the mag springs with wolf extra power ak mag springs and replaced the firing pin. Ive yet to see the bolt breakage problem and i know theres at least 4k of rounds through it. I did ask bushmaster about it when i first got it and they said they allready addresed the problem.
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Old August 1, 2011, 08:35 AM   #15
chewie146
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Did you replace the firing pin with something special? Is there something better for those hard primers? His springs seem to be fine.
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Old August 1, 2011, 12:51 PM   #16
Lloyd Smale
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chewie i forget where i even bought it but it is suppose to be an extended fireing pin that gives a bit deaper hit and its made out of a differnt material thats suppose to be more durable but ive yet to break an ar firing pin so i dont know how important that is.
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Old August 1, 2011, 07:52 PM   #17
MMcfpd
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Model 1 Sales' 7.62x39 firing pin (top, below) is machined so the tip protrudes further from the bolt face to give a deeper primer strike:


They work well on the hard primered eastern european steel case ammo (Wolf, etc.) and I use them in conjunction with lobster tail bolts from LMT:


The C Products (now ASC) mags in 10 and 30 rounds work just fine, as do the out of production USA 20 round frankenmags:


I've found several on Gunbroker and arfcom's EE.

7.62x39 in the AR is great; after having one for a while (I have three) I sold my AK.
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Old August 1, 2011, 09:05 PM   #18
chewie146
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Wow, cool. Thanks for the replies. I appreciate all the help, everyone.
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Old August 2, 2011, 06:54 AM   #19
Lloyd Smale
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thanks mmcfpd. thats the pin.
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