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View Full Version : Anyone here do a 7.62x39 CA AR Build?


PLINK
01-15-2007, 1:08 PM
I was wondering if anyone here did a 7.62x39 AR build? If so, I would like to here about your experience with it, where you got your parts and pics of your build if you got them. I did a search here and did not find much on the topic.

I was thinkning of building the upper from scratch using a Mega upper receiver and going from there.

I am gong to continue the search on other forms to see what I find.

TIA.


**I don't want this thread to turn into a "why don't you just by a 6.8 SPC". I am already buying 7.62x39 for other rifles and and the ammo is somewhat cheap compared to 6.8 SPC. Just wanted to hear experiences on how it works for the AR platform. Thanks

stator
01-15-2007, 1:46 PM
Well, I do not see how you cannot expect it to turn out to be a 6.8SPC thread, because it is your better choice. The problem with 7.62x39 is the case head. It is thicker and to accommodate it in an AR platform, the bolt is inheritently weaker. Bolt breakage issues is not uncommon.

If cheap ammo is your choice, stick with Wolf 5.56 instead. Otherwise, if you are looking for something with more caliber, I'd recommend 6.8SPC.

bwiese
01-15-2007, 1:50 PM
If you didn't have preban AR 7.62x39 mags before 2000, you likely won't have a really great operating rifle.

The Colt 7.62x39 conversion kits/mags had a poor rep for feeding as they'd only work with 5 rounds or so before feed problems within the mag became apparent.

Tapered rounds like 7.62x39 don't like straight-wall magazines (or segments thereof).

The only mags for ARs in 7.62x39 worth their salt were some oddball hybrid ones that had AK mags with an AR top end.

fun2none
01-15-2007, 3:16 PM
Giving the rising cost and scarcity of .223/5.56 surplus ammo, I looked into a 7.62x39 conversion. There quite a bit of information on ar15.com forums.

As previously mentioned in Bill's post, there is good chance that there will be feeding issues related to magazine curvature and lip profile. I passed on the 7.62x39mm conversion for this reason.

duraglock
01-15-2007, 5:35 PM
i have 3. 2 colts and a ja nd t. also have the mgi lower for ak mags and a mgw 10rd fixed mag lower that works fine. i think if you get the right parts its not a problem. when c products comes out with there mags look for more vendors to start making more parts for this caliber. yes 6.8 is better but 7.62x39 is cheaper . no surplus 6.8.

cornholio1
01-15-2007, 5:41 PM
I have one on an AR platform. Its flawless after some debugging. Works great. Mags are hard to find. The best I've tried are MWG mags. You must also shave about 7/1000ths of an inch off the back of the bolt so th firing pin can protrude further. You must do this if you want to use cheap plinking ammo. Pedigree Ammo like Winchester/Remington 7.62x39 have softer and almost flush primers. Wolf and other Russian ammo have harder and deeper set primers. Visit gunscal.com for my post on this there. BTW a wolff extra power spring will help a lot


Heres how far you should trim the bolt.
http://i81.photobucket.com/albums/j225/usadaytrader/IMG_2627.jpg


This is a 16" 7.62x39 AR (using std AR receiver)
http://i81.photobucket.com/albums/j225/usadaytrader/76239ar.jpg



Heres the mag
http://i81.photobucket.com/albums/j225/usadaytrader/IMG_2624.jpg

PLINK
01-15-2007, 6:24 PM
Visit gunscal.com for my post on this there.

Gunscal is no longer available.:(

Did you do the shaving on the bolt yourself? Who makes your upper?


I failed to mention that I would be using a standard AR style lower. I know they have the AR47 that uses AK mags. I just have some lowers that could be used for this project. And was looking for something different and in a caliber I am already buying.

Thanks guys. Keep the info coming.

cornholio1
01-15-2007, 6:32 PM
Gunscal is no longer available.:(

Did you do the shaving on the bolt yourself? Who makes your upper?


I failed to mention that I would be using a standard AR style lower. I know they have the AR47 that uses AK mags. I just have some lowers that could be used for this project. And was looking for something different and in a caliber I am already buying.

Thanks guys. Keep the info coming.

Mine is an AR style lower as well. I didn't like the "hybrids" I shaved the bolt myself after doing tons of research on ar15.com. I used a fine triangular file (slowly) and kept measuring it with a micrometer. I'll try and remember to post some pics tonight. The upper is a Model 1. All 7.62x39 AR uppers that I know of (including Colt) have FTF problems if you don't do the mod.

After doing the Mod, I have 0 FTF with Wolf or Brass Ammo. Its very accurate as well. Less than 1" MOA@ 100yds with Wolf.

SunriseF150
01-16-2007, 8:04 AM
I have a 7.62x39 AR. In fact it's the first AR that I built (half way) out of my 4 receivers. I used a Mega lower w/ RRA lpk with NM Stage 2 trigger. The upper is a A3 Colt Sportster Conversion from 94, complete upper. I just made sure it was cleaned and lubed and dropped it on.

The mags I use are the USA Magazines like this one http://www.gunbroker.com/Auction/ViewItem.asp?Item=64209866 They are great. I have a Colt mag that looks like a 20 rounder but only holds 7 rounds. I had 2 of those MWG mags that I bought. They are plastic and well after shooting the gun for the first time this weekend I tossed those mags in the trash. They are garbage and don't waste your money on them. Get the USA mags, they are metal and have a nice thick rubber base. Made very well.

I shot about 100 rounds through it this weekend and 1 problem with it. That was when using the mwg mag cause the tip of the bullet was hitting the lip of the mag and getting caught (so out those went). Other that that not one single problem using the USA mags. I was shooting Winchester ammo out of it that I got from Wal-Mart.

I do plan to build up the other lowers into a 6.8, a 5.56/223, and really want a 458 socom one as the last.

cornholio1
01-16-2007, 8:23 AM
I have a 7.62x39 AR. In fact it's the first AR that I built (half way) out of my 4 receivers. I used a Mega lower w/ RRA lpk with NM Stage 2 trigger. The upper is a A3 Colt Sportster Conversion from 94, complete upper. I just made sure it was cleaned and lubed and dropped it on.

The mags I use are the USA Magazines like this one http://www.gunbroker.com/Auction/ViewItem.asp?Item=64209866 They are great. I have a Colt mag that looks like a 20 rounder but only holds 7 rounds. I had 2 of those MWG mags that I bought. They are plastic and well after shooting the gun for the first time this weekend I tossed those mags in the trash. They are garbage and don't waste your money on them. Get the USA mags, they are metal and have a nice thick rubber base. Made very well.

I shot about 100 rounds through it this weekend and 1 problem with it. That was when using the mwg mag cause the tip of the bullet was hitting the lip of the mag and getting caught (so out those went). Other that that not one single problem using the USA mags. I was shooting Winchester ammo out of it that I got from Wal-Mart.

I do plan to build up the other lowers into a 6.8, a 5.56/223, and really want a 458 socom one as the last.


I actually had problems with USA. MWG is the best i've used.

rick1881
01-16-2007, 9:28 AM
Thanks guys for all the help & input...Weird thing is snap caps cycle fine winchester brass just caused the mag follower to go verticle.

I also was using a Mega lower and an Model 1 Upper (7.62-39) w/MWG Mags.

rick1881
01-16-2007, 10:54 AM
Gunclip Depot <gunclips@ca.rr.com>

Just orderd mags from this site, check it out he has lots of stuff.

Rick