Robocop1051's 7.62X39 Project

[Robocop1051]

In my unrelenting urge to build, build, build, I have decided to reinvest into an old plan... Thanks to Imschur and 98Z5V, I'll be dabbling in FDE as well as I have been bitten by the FDE bug.

• Started with a LMT lower and RRA trigger
  
• Had to have the Battle Arms Development BADASS <thumbsup> (bought months ago, looking for a home)
  
• Troy VTAC Alpha 15" Battlerail - FDE (Ordered from Riflegear.com)
  
• RRA Operator A2 fixed stock in FDE (Ordered from RRA)
  
• MGI Enhanced 7.62x39mm Bolt with Firing Pin (www.thegunsandgearstore.com)
  
• Colt AR-15 Carrier (I had an extra one)
  
• VLTOR/BCM Charging handle (Brownells)
  
• Magpul trigger guard in FDE (Brownells)
  
• Magpul MOE+ FDE Grip (Brownells)
  
• Magpul MBUS in FDE (Brownells)
  
• Ergo magwell grip in FDE (Brownells)
  
• YHM 16" fluted barrel w/ LoPro Carbine GB (bought local)
  
• PWS FCS Custom .30 cal (1/2"x36) (Ordered from PWS)
  
• YHM Upper marked "7.62x39" (bought local)
  

Ammo was $206 per 1k rounds at the local gun show. Gonna be one hellofa fun-gun! <thumbsup>

I'm headed to the Reno, NV Gun Show this Sunday. Stay tuned!

[imschur]

Thats the spirit!  <munch>

[unforgiven]

$206.00 for 1k rounds= loto fun  ;)

[Robocop1051]

Whoa baby! Brownells, RRA, Rainier and PWS all sent their packages this week... So close I can almost taste it.

[washguy]

Whoa baby! Brownells, RRA, Rainier and PWS all sent their packages this week... So close I can almost taste it.

Geez Robo  great minds think a like!  I just this weekend decided to take one of my cherry gunsafe queens an original colt sporter 7.62x39 and started ordering new furniture ,stock,and trigger group....I know this is prolly the wrong thing to do and will devalue the rifle,but im bored <laughs>  Wash

[imschur]

<thumbsup>

[Jgun]

Can't wait to hear how this one runs for you, Good luck with the build.

[Robocop1051]

Just a little sneak peek at the pre-assembly parts

So close I can smell it.

[washguy]

Way to go Robo !    I got screeewd on my 762 redo <laughs>  My midwest industries freefloat hand guard was missing a piece when it came in yesterday. I emailed dealer last nite but didnt get response this morning....so went off on a tangent called midwest and got the ol cant take a msg cause all mailboxes are full <dontknow> well I was peo'd on that and emailed em and said " I guess that customer service aint happening"  Whoa  got three different emails from three different people that the missing part is being shipped and what size t-shirt do I wear so they can send me some....okay  Kudos To midwest and then vtsupply.com also for getting intouch with me and fixin the problemo.....daamn i was wanting to go shoot the redone colt 762 this weekend ;)  Wash

[Jgun]

Just for my education, can you remind me what parts in the lower need to be proprietary to the 7.62X39, or is it just in the upper? Am I correct that you need barrel, BCG and upper receiver to be 7.62 X39 specific? What about the buffer/spring ?

[Jgun]

I forgor to ask, Is your 300BLK finished? If so, I will be interested to hear your side by side accessment of the merits, faults of each. Do you know how many rds you'll be getting in a mag?

[Robocop1051]

OK, So the 300blk is still a work in progress. The barrel I ordered in March still hasn't arrived (Wilson Combat 14.7" 1:8). I'm hoping that this is rectified SOON.

The 7.62x39 is a simple process. The lower remains the same (although I'm upgrading the furniture on mine). The upper receiver is a standard upper. I purchased the one with the cheapo writing on the side "7.62x39mm YHM" just to minimize confusion down the road.

The only parts that need to be swapped are the bolt and the barrel. Everything else is standard. I chose a 16" barrel with carbine gas. This is because the 7.62x39 surplus stuff is already an under-gassed bullet. The guys with 16" mid length barrels are having cycling issues when shooting the cheap brown case surplus commie rounds. The most important part I added was a stainless steel extractor to last longer on the steel cased commie rounds. I also grabbed a longer firing pin to get a better strike on those thicker (and sometimes recessed) military primers.

There are places, like AR15 Performance, that make a special bolt (and I think barrel extension) for the 7.62x39. He swears his is better quality. I also think the guy is full of a lot of hot air, and would autofelate every chance he gets to show how cool he is.

If I'm getting too much gas/kick, I'll get a heavy buffer or CWS to counter the impact and slow things down a bit.

As for magazines, since the 7.62x39 is a tapered casing, I have to use proprietary mags. This is the original reason why I started building the 300 blk instead. The 7.62x39 mags are more "banana" shaped and hold 30 rounds. They are very similar to the old 45 round 5.56 mags.

[Jgun]

Sounds pretty straightforward. I'm glad that you will have both (eventually) to give a first hand comparrison. I'm going to be especially interested in what you find to be the bullet drop and max accurate range of the two (out of your length barrels obviously).  I've never found the 7.62X39 to be all that accurate, but to be fair I've never shot anything but mil ammo out of AK's, so that's probably not representative of the level of accuracy that the rd is  capable of.  I've read some postings comparing the two, but it will be enlightening to hear it directly from a source that we can trust. Good luck with it.

[edgecrusher]

hey robo, the cproduct mags fed my 7.62x39 better than any other fyi.

[washguy]

Hey Robo  you old enough to remember these?

1990 frankenmags 40 rounders for my 762x39....I guess the Cali boys would be in trouble for just touching one of these <lmao>Wash

[Robocop1051]

I was actually looking at doing this with some old mil issued mags I have in the garage.

[washguy]

Hiya Robo    thanks to fast service from midwest industries got my missing frontend cap....so slapped the ol 762 together just now...heres a pic....now for the funny part...i was prowling around inside my gunsafe and found another 762x39 sp1 sporter <laughs>  so I got furniture and a flattop on the way...yep..I know im screwing up a pefectly fine sp1 colt <laughs>  Wash

[Robocop1051]

I'm still waiting on my MGI Enhanced Bolt to arrive, and my MBUS are still on back order from Brownells.

Pictures will be up soon.

[washguy]

I'm still waiting on my MGI Enhanced Bolt to arrive, and my MBUS are still on back order from Brownells.

Pictures will be up soon.

Geez Robo  I hate when that backorder thing happens!

meanwhile dont ya just love it when all the parts come in on a friday afternoon and not one thing missing?

So heres  the second 762 built today ;) Wash

[unforgiven]

Nice job brother Wash. <thumbsup>

[Robocop1051]

:rant2: >:(

I'm still waiting!

[Robocop1051]

All done!!

[edgecrusher]

how do you like the rra stock? how is the weight compared to a carbine set up?

[washguy]

Robo    SWEET!  <thumbsup>  Wash

[Robocop1051]

This is  amazingly lightweight rifle. The first word out of my wife's mouth was wow.

The RRA stock is very comfortable, and balances very well. If youre used to the A2 stock this will fit like an old pair of jeans. The 16" fluted barrel swings surprisingly fast. I have no problem pointing one handed.

I'm still shocked how thin the Troy/VTAC rail is. After handling it for a bit, I think another AFG1 is in my near future.

Still waiting on mags and MBUS to arrive.

I ordered some "rebuild kits" online. Even though I'm allowed to buy mags from the store, I have issues ordering online. Since this build is ultimately going to my cousin, I'm going to make some 10/30 mags with a rivet gun.