Gunco Forums banner

Green moutan barrel blank (7.62x39)

15K views 63 replies 23 participants last post by  1biggun 
#1 ·
#2 ·
I just ordered one. I really wish it was not profiled. I rather be able to keep it heavy for a target build. wish they would also sell one unchambered.

I will stick it on a AMD 65 kit and see how it works. the price is right I see its cut rifleing.

Im sure for $30 it will be top quality LOL. I may rechamber it using my reamer see what I get first.
 
#9 ·
Agree with everything except that it's cut rifling. Button rifling is listed by Green Mountain, and that is not cut rifling, but rather is a type of cold forming where metal is not removed, but rather displaced.
 
#8 ·
You'll have to machine the barrel anyway. Its not machined for size externally.
Its says AK profile so Im not sure what that is going to be. I hope it is over size. Ill post when I get it. mine was $36 shipped. Im a little unsuure why there so cheap as well. I want to build a target set up but with a 311 bore so i can also shoot surplus ammo with out the pressure increase. 20" is fine with me it will add about 150 or more FPS. I wonder how long they will have them?? I almost called them today.
 
#12 ·
They charged me the MI 6% tax. I suppose it's the "get as much as you can for these barrels Jenkins, or you're fired" kicker.
I wonder who will be the first one to chuck one of these up in a drill press and finish it with files and sandpaper, you know it's coming.
 
#11 ·
yesterday i talked to dennis from gmb and he said it's machine finished oversized. he said he'd try to get a picture and the measurements on the gm website within 24 hours he said their whole idea behind them was the home builder with lathe access pretty much so we can make our odd ball barrels easier (tabuk, long akm, etc)
 
#15 ·
Mildly deceptive but it sound like a fun project still. I guess I'll need to get a X39 reamer now. I wonder if they'll have them for sale at GM in a day or so. They have pics up now also, that would made things a lot clearer from the begining. I was going to pick up a few of them but I think one will be enough for now.
 
#16 ·
I just got off the phone with Dennis at GM. The first thing he mentioned was that, despite what the web site says, they're not chambered, and he apologized about it.

When I told him I'd heard about the sale on gunco, he asked if I would mind posting something about the chambering thing.

Most of GM's barrels give a typical cartridge, like ".40-65", and I've had to look up the cartridge specs to guess what the size of the barrel was, so it's consistent, if misleading.

Anyway, they're straight 1" rifled tubes, no taper, steps, tenon, or other machining. I bought two. He said they've sold a ton of them in the last couple of days.

He said the price should be good all summer, and that they were going to greatly expand their lineup of military-style barrels. The ones closest in the queue are various AR-15 barrels.
 
#18 ·
The barrels are 1"x20" unchambered non profiled .310" rifled blanks. I have no idea why they advertise them as 7.62x39 when that is a chambering. They could advertise them as 7.62x25 or 7.62x54 or even 32 ACP for that matter.
Sweet. I have the reamer for the x39 an at 1" they would work on some bolt actions (not remington 700) like the mosin or ruger or win. I see a 1" bull barrel target build coming soon that will also shoot factory loads. Now I need some one to make cheap over sised gas blocks or a sagia shot gun clone. If there decent I may get a few and chamber them and sell them possably. a 1" bull barrel mosin would be cool.

there add is very missleading it says profiled and also 7.62x39 which it is not. I hope they come out with some 5.45 blanks also in the same price range Id jump all over that.
 
#19 ·
Yep, got the email too.
I agree, they should have mentioned about the "no chamber" thing, but oh well I'll send it to 1biggun and let him do it. :D

I think it's a good deal yet and not bitch about it.
 
#20 ·
Being a barrel blank It does open up some possibilities. I wish it was the longer blank that they use to make the rpk barrels, but I guess beggars can't be choosers.

I have a 1895 Chilean Mauser that that would be a nice conversion to 7.62x39.

Could do a heavier barrel psl carbine....
 
#26 ·
well profiled would be if it is turned to fit something or has some thing done to it other than a turned blank.

a straight blank os just that a straight blank it is not profiled to a AK in any shape way or form. for me that is a good thing for a guy who thought he was getting a 20 long barrel that was profiled to take AK parts he is SOL.

Im actually really clad to see these. i get request frequintely from guys asking if I can do a heavier longer barrel that will still shoot surpluss and factory .311 bullets. this will make this possable. I think a fluted 1" bull barrel AK with a 20" barrel would shoot pretty damm good if you do some of the stuff I did on my other builds. It will be interesting to see how they perform. If they shoot good I might make a few extra up for sale or trade. They would work on a mosin nagant as well fro a cool build. I wuld like to see them 24" long but Its a start. you can also build a couple 10" pistols from one as well.

For a guy with a lathe and a reamer this will allow some savings on building a barreless kit and also give the option of some really unique builds. I will do a straight unfluted bull baarrel build on a beater gun I have here and see how it shoots. I may have to re work my reamer to take a .311 pilot as mine is currently a .308 fixed. I may just buy a new one with a slightly tighter neck and less bullet lead to help the accuracy some.

I wish they had a 1-15 or slower option. I think the standard AK twist is way to fast. IMOO I see no reason for a twist rate that will stabelie a 200 grain bullet it makes no sence to me.

I HAVE PLAYED WITH PULLENG DOWN FACTORY AND SURPLUSS AMMO AND LOADING THE CACES WITH BETTER POWDER OR REMEASURED POWDER AND QUALITY BULLETS IN .310 WITH SOME DECENT RESULTS. i WISH THERE WERE MORE BULLET SELECTION OUT THERE.
 
#28 ·
Would be a little loose for a 7.62x25 all of the surplus I have measured was 308 or a little under. One in 9.5 twist is quick for 7.62x39 and even more so for the light 7.62x25. Have seen some take off barrels for 30-30s with a 1 in 12.

Back to x39 and x54r I was wondering around Green Mountains web page and did notice they have 32-20 WCF pistol blanks. 11in long, 1 in 16 twist, and land of 306 and grove of 312. Could work for some of the surplus, but the wolf hp that I have measured is running around 308.... 32-20 WCF Cartridge pistol blank

Haven't found any barrels like what the CZ527 in 7.62x39 uses, .300 land and a groove of .311.
 
#32 ·
got mine today its a unprofiled unturned blank in hopefully a 311 bore ( I havent slughed it but sticking a bullet down in id say its close. its saw cut on bolth ends. Ill have to get it in the lathe and turn it on centers to see how consintric it is. but for $36 dollars shipped it will make a barrel for any AK as long as its under 30" it looks just like the picture above

when i get time ill chamber it and make sure its true to the centers and if it is ill turn the trunion end to 23 mm and leave the rest large and crown it and do a bull barrel target barrel with out gas port or GB and see how well it can shoot. the out side is a smooth black. looks like one inch rod with a hole in it. hope fully it will be fairly consentric.

IMOO the ads says profled and to me that means even if its straight it should be turned on centers. if its a straight or tapered or steped profile it should have been turned. this should be a advertised as a .311 20"x1" OD unturned blank with the correct twist rate given. Im not going to biuth as its what I really wanted but I can see how others will be disipointed. If it shoots i may get a few more to set up as plug and play target barrels for sale. Id like to be able to buy other calibur blanks like this for that price. a 5.45 for instance woud be nice as well as a 223 and .308. Id but a bunch of 6.5mm" blanks as well for that price.
 
#33 ·
the twist rate is fast. I really dont get the reason for the Ak,s using such a fast twist unless the equipmint was left over form doing Mosin barrels and they just never changed it. its even fast for a 150 grain bullet IMOO. 30-06 and 308 use mostly 1-10 as well as most other 30 caliburs that normay shoot 150 grain bullets they use 1-10 because they also shoot up to 200 grain bullets as well. in all but a supressed application a bullet over 150 is pretty much pointless in a AK as its just to damm slow. if good bullets are used its fine as overstabelising will not affect a consentric bullet as much but if the bullets are out of spec a little then that high rate of spin will hurt accuracy.

a couple good links here about twist rates and using a to fast of a rate.

Barrel Twist vs. Bullet Weight


30BR Guide - 30 BR Benchrest Lapua Cartridge with Reloading, .308 Bullet, Accuracy, and Competition Info

Barrel FAQ -- Barrel Velocities, Lengths, Twist Rate, Contours, Cleaning, Accuracy and Ballistics for Benchrest, Hunting, Precision Shooting

I have a 30 BR barrel in 1-17 that I plan on rechambering to .308x39 some time and see how it does.
 
#38 ·
the twist rate is fast. I really dont get the reason for the Ak,s using such a fast twist unless the equipmint was left over form doing Mosin barrels and they just never changed it. its even fast for a 150 grain bullet IMOO. 30-06 and 308 use mostly 1-10 as well as most other 30 caliburs that normay shoot 150 grain bullets they use 1-10 because they also shoot up to 200 grain bullets as well. in all but a supressed application a bullet over 150 is pretty much pointless in a AK as its just to damm slow. if good bullets are used its fine as overstabelising will not affect a consentric bullet as much but if the bullets are out of spec a little then that high rate of spin will hurt accuracy.

a couple good links here about twist rates and using a to fast of a rate.

Barrel Twist vs. Bullet Weight


30BR Guide - 30 BR Benchrest Lapua Cartridge with Reloading, .308 Bullet, Accuracy, and Competition Info

Barrel FAQ -- Barrel Velocities, Lengths, Twist Rate, Contours, Cleaning, Accuracy and Ballistics for Benchrest, Hunting, Precision Shooting

I have a 30 BR barrel in 1-17 that I plan on rechambering to .308x39 some time and see how it does.
This has been on my mind as well. If there is a good reason for the fast twist in the AK, I would like to know it. The big queston is how much better would an AK in 7.62x39 shoot with say a 1:15 barrel using the standard 120-130 gr bullets? I'm not a benchrest shooter but if I could hit things at long range with the AK that I could not before that would bring a smile to my face. :)
 
#35 ·
1biggun, does the barrel have a mark on it at either end to tell you which end is the chamber end?
NOPE none that I could find. Ill likey face off each end and wahat ever end swallows the the bullet the most will be the breach. Im not sure what else to do? I cant tell if one side of the rifleing is sharper than the other or any thing like that. Im looking for suggestions. I might call them and have a few words with them.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top