Need advice on an upper build for a light machinegun

General Firearms NFA
1

Need advice on an upper build for a light machinegun

Will be used strictly for local MG matches to compete against heavy beltfeds.

Must be capable of sustained fire with bursts from 20 to 200 rounds per match round.

Shooting 55gr. and 62gr. FMJ brass cased ammo (American Eagle, Honaday, and WWB)

Feed mechanisms are Beta mags

Ranges from 50-300 yards typical

Not concerned with “sub-MOA” accuracy. Smallest target size at any range would be 8" round steel.

Requesting advice on a barrel for the above, need suggestions on:

  1. Barrel length
  2. Gas system length
  3. Twist rate
  4. Barrel profile

I was thinking BCM but they don’t seem to do heavy barrels unless I’m overlooking them on their website. Maybe I don’t need a heavy barrel, I don’t quite know, thus the reason for this post.

2

i would think a heavy barrel and chrome lined for sustained full auto fire would be appropriate. i would still opt mid length 16".

3

I would think Noveske (they use SAW barrel material) crome lined 16 inch.
Course if I was doing shenanigans like this I would opt for a 240.

4

Both the Noveske CHF barrels and the Centurion Arms CHF barrels are made with M249 barrel steel, rifling, and 2x thickness chrome lining. Supposedly they are both actually made from legit FN CHF M249 barrel blanks.* The exterior profile varies slightly between the two, but either should be sufficient for your needs. Unfortunately the Centurion’s are currently out of stock and I don’t believe Noveske is selling CHF barrels separately anymore. But if you aren’t in a hurry, that’s probably your best bet.

*This has not been verified by FN, Noveske, or Centurion to my knowledge, but has been inferred by others more knowledgeable than me on the subject.

5

I guess I should have added that the next match is October 12th. Looks like that takes Noveske and Centurion out of the running.

Nobody for a 20" barrel?

Jason0311: I’d be all over an M240 too… but I seem to have left that $70,000 in my other pants… bummer. :wink:

6

I would also look at one of the BCM M4A1 uppers. They have a heavier profile and could work for what you are using it for.

7

Palmetto has those same FN made barrels for less, but to me it sounds like you are looking for a SOCOM M4 barrel.

8

Just pick up one of these. It will out shoot any LMG out there for accuracy even though it is open bolt. I can hit tannerite targets reliably at 200-300yrds with short burst. For the long burst you need the heavy gas tube that is used in the LMG upper and as far as I know no one had made them for the market.

http://www.youtube.com/watch?v=WriIGNW1nKY&feature=share&list=PL2E2DA54747606369

9

I know Noveske barrels are basically M249 barrels with the heavy chrome lining. I like mine but I couldn’t possibly shoot enough to burn out a standard Colt barrel let alone a Noveske chrome barrel.

Edit: missed the post already made about Noveske barrels … I would add that a switchblock would be a valuable tool if you are going to suppress especially in FA :slight_smile:

10

I would use a 20" barrel, for a variety of reasons but chiefly for reliability in automatic. I’d also use an A5 or A1 stock.

11

I’d get a Colt LMG upper.

Does this have to be mag feed?

Can you get a Ares Shrike upper?

12

Beautiful Colt Automatic Rifle/LMG Mongo!

I was weighing one of those against a Shrike. The only problem with the Colt LMG upper is that while not difficult to acquire, the FCG is TOTALLY IMPOSSIBLE to acquire. I have seen one Colt LMG FCG for sale, ever, and while not recalling the price I do recall my shock at the price. But itt is my understanding that they will function in both open bolt (which requires the OEM Colt LMG FCG) and closed bolt (any M16 FCG) configurations.

20" barrel on that LMG. I agree with RyanB and am leaning towards a 20" barrel. Looks like Colt is one of the few making a heavy barrel these days that isn’t stainless.

Noted and agree on the Noveske switchblock. I have two on other rifles currently, becoming a standard item on my builds.

scottryan: I was looking at a Shrike as well. Belt-fed is preferred but the ranks of the machinegun competitors have dwindled so much this year with the cost of ammo the rules now allow for magazine fed rifles as long as it is a rifle, firing a rifle caliber round. Yes, and M16 looks a little silly sitting amongst Vickers, 1919s, an M249 and TWO MG42s on the firing line… but what the hell… it’s the spirit of the particpation, right?

I’m also looking for a lower cost solition than a Shrike.

Thanks for the suggestions fellas. I’ve got what I need to know. :smiley:

13

I’d just get a 20" HBAR if the LMG upper is too hard to find. The rifle length gas tube won’t melt as soon as shorter lengths but I would keep a few spares on hand.

Open bolt would be nice if you get the barrel into cookoff temps, but for a game gun I wouldn’t worry too much about it. As long as you can keep it pointed in a safe direction and are not running around with a round chambered.

14

My thoughts exactly, this is precisely what I intend to do.

The matches are largely stationary so a cookoff, while being a dangerous situation, isn’t that big of a deal. The Match Director is EXTREMELY safety conscious and all the participants have had their MGs for a long time (two MG42s! you know what those go for these days?!?) and know how to handle adverse situations like that.

Thanks Todd.K