BCM Dissipator- Yes or No?

[Stickman]

Bravo Company MFG has been kicking around the idea of making a dissipator for a little while. WEVO Staff was able to get ahold of one, and wanted to get the thoughts of all of you guys out there.

In this case, the BCM Dissy is a using their BCM Midlength gas system on a 16" Cold Hammer Forged (CHF) barrel. In typical BCM fashion, this barrel is proof fired and MPI tested. The F marked front sight base is pinned in place, and the hand guard cap is screwed into the FSB so it can't come loose. The gas block is pinned in place and properly spaced.

The advantages of the rifle length hand guards on a 16" barrel are pretty straight forward. The standard rifle hand guards are plastic, and very light weight. The upcoming Magpul MOE rifle length hand guards are very light weight as well, and they are what I believe most shooters will be interested in using. The MOE hand guards offer a variety of mounting solutions for lights and VFGs. A 2 piece drop in rail is also an easy cure for those people who have a love for extended rails or a need to mount precision devices such as lasers or optics.

The extended space of the hand guards prevent heavy shadowing of the barrel when you are using a light, an important feature when clearing rooms or using a light in real world situations. The extended room also allow for a more forward hand grip when shooting, a method which has become increasingly popular for muzzle control.


My question for everyone is this, do you think this is a concept which Bravo Company MFG should pursue, or do you think they should stick with more traditional models?

[Stickman]

These images show the pinned FSB and gas block.

[Stickman]

Here are the railed versions.....

[rob_s]

I can understand the attraction, and 12+ years ago I sold more BM Dissipators than any other model. I even still have one in my safe. But I'm not sure that what was applicable then is applicable now. At the time flattops, and RDS were just barely making an appearance and we still sold way more A2 rifles for anything other than long-range shooting, and the longer sight radius of the Dissipator was attractive. Also, railed handguards, especially free-float type, were not at all common. Some folks were using the KAC 7" but that was about it.

Today, anyone that wants to can simply chop their FSB and run a 12.0 or even 13.0 rail over it and attach a flip-up front sight and actually wind up lighter, and more capable, than rifle-length plastic handguards and a full FSB. I have found that quite often the notion that a set of plastic handguards and FSB is lighter than a rail system turns out to be incorrect once you add a way to attach a light, sling, and VFG. Even in trimmed-down form there really isn't a weight savings.

I wouldn't discourage BCM from making them, and I'm sure they'll sell some, but logically it doesn't necessarily add up and I'm not sure the same benefits apply today that did 15 years ago.

[Paulo_Santos]

Personally, I'd prefer to have a 12" FF handguard with front and rear flip ups, but If I were to use the regular FSB, the Dissipator is pretty nice.

[Wondering Beard]

I'm a newb when it comes to ARs so my opinion isn't as learned as nearly all of you.

I find the concept interesting for the reasons Stick mentioned but only if we're talking about keeping plastic handguards, especially the MOE type.

I have found that the longer the railed handguard, the more the balance moves forward and needs to be compensated for at the rear which then continues adding weight to a rifle which is meant to be light; add to that an FSB in the front and it might start getting awkward.

If the handguard is a rifle length MOE which enables one to mount accessories easily then ok as the weight and balance are likely well preserved but since it won't be free-floated, which rightly or wrongly people seem to prefer, there just might not be that big a market for it.

As I look to the ways I would use my AR, while I am intrigued, I most likely wouldn't buy one.

Edit:

I just went back to watch the milspecmonkey video from SHOT 2010 about Magpul which features the rifle length MOE handguard on a BCM Dissipator and I believe I'm changing my mind. Adding only a light and a red dot optic would make for a much more practical carbine than I originally thought. All of that is so long as it's with an MOE handguard and would be even better with a pencil barrel.



I hope it's all right to embed the video, if not tell me, and I'll remove it.

[HeavyDuty]

Oh, hell yes.

I have a very strong preference for FSBs on my ARs, and midlength Dissapators are of great interest to me. My one suggestion would be to make a version with a pencil profile - 0.590" nominal OD with 0.625" journals for both the gas block and the FSB.

[sjohnny]

What is the benefit to this over a rifle length gas system?

[HeavyDuty]

16" barrel vs. 20".

[Stickman]

Oh, hell yes.

I have a very strong preference for FSBs on my ARs, and midlength Dissapators are of great interest to me. My one suggestion would be to make a version with a pencil profile - 0.590" nominal OD with 0.625" journals for both the gas block and the FSB.

I strongly agree with you. I see a large benefit in a setup like this coming from an affordable light weight setup.

While rails are extremely popular, they are also adding several hundred dollars to the price of a weapon. With the money that you would spend on a rail, you could be getting an optic (or saving enough money to be close to buying one).

[sjohnny]

16" barrel vs. 20".

Why can't you have a 16" barrel with a rifle length gas system?

[Stickman]

Why can't you have a 16" barrel with a rifle length gas system?

Your gas port is to close to the end of the barrel and it creates issues.

[hikeeba]

...logically it doesn't necessarily add up....

Logically, no. Emotionally, perhaps. I can see it as having a sort of throwback or retro appeal for those who loved the original Bushmaster Dissipator idea. Not that there would be anything wrong with that. And after thinking about it a little more, I suppose someone could make it logically add up for their particular application. Different strokes for different folks. Or if they had an original Dissy with a rifle-length gas setup, maybe it was different short strokes for different folks. Nyuk nyuk.

It's neato and all, but not for me. While I'm keen on the Dissipator concept applied to a 12.5" SBR, a 16" 'Kino Configuration,' not so much.

Why can't you have a 16" barrel with a rifle length gas system?

Dwell time (time from when the bullet passes the gas port to the time it exits the barrel) is too short, resulting in not enough gas pressure left behind the bullet to cycle the action reliably. Or something like that.

[Stickman]

[sjohnny]

Thanks guys! I'm still new to a lot of this.