Downward Vent BCG - Useful or Not?

[rlsmith1]

My first impression is I’ll notice the extra fouling in the magazine more than I’ll notice the reduced port noise.

Seems like a nice BCG though with some thoughtful features like PVD coating, modified carrier rails and dual ejectors. Thoughts?

https://kakindustry.com/k-spec-enhanced-ar15-bcg-5-56-300-blackout-dual-ejector-down-vent-sand-cuts-fde-pvd-chrome-lined/

 

[LRRPF52]

If you diverted the gas to the outside of the feed lips rather than into the magazine, that might make sense.

They say they have the testing to back it up.

The main benefit claimed is reduced port noise running suppressed, which makes sense.

This photo looks like the gas will blow into the magazine though, but I seem to get fouled cartridges in presentation running suppressed anyway. Look under the bottom carrier rails to the rear to see the redirected vent ports:

 

[LRRPF52]

First response from many will be, “This takes sh*ts where it eats to a whole new level."

 

[rlsmith1]

I was wondering if there was a way to bypass just dumping the gas straight into the magazine, that sounds like a good idea.

Guess I have no idea how much noise / gas comes out of those ports to start with.

Part of the reason I said I think I’d notice the increased magazine fouling is because I’ve seen the same thing on those first few rounds even with a regular BCG.

Always nice to see fresh thinking to keep things moving forward (even though not all of it pans out).

Maybe I’ll wait for them to go on sale and see how they are

 

[ut755ln]

I was wondering if there was a way to bypass just dumping the gas straight into the magazine, that sounds like a good idea.

Piston

 

[supercorndogs]

My adams arms piston gun was filthy when shooting suppressed.

I was under the impression most of the action fouling when shooting suppressed was coming out of the barrel through the chamber. I also thought the pop was from the same, not gas venting from the carrier.

 

[Cascade Hemi]

Most piston systems vent to atmosphere at the gas block and are loud as a result.

 

[rlsmith1]

This got me thinking about BCG ports and thought I'd share the video below. If you slow down the video to 1/2 speed, you can see there are 2 impulses of gas coming out of the port; one before and one after unlocking (with more gas coming out after unlock). Seems reasonable to say port noise is reduced with these.

@supercorndogs I've heard the same thing on most fouling coming down the bore on suppressed rifles.

 

[bfoosh006]

I would be curious if the downward exhaust ports, which appear to above the feedlips of the magazine... might eventually Melt any plastic feedlips. ?

As for the dirty aspect... go to about 8:30 in the video.
I am not sure how much the filth would matter... unless you reloaded the same mag quite a few times.




And the Egg test....

 

[bfoosh006]

"K-SPEC VS MILSPEC SOUND TEST K-SPEC WILL MAKE YOUR SUPPRESSED AR15 QUEITER"

https://www.dropbox.com/scl/fi/bnnm...ITER.png?rlkey=b36gf8brbwly3128g7x2rpf3e&dl=0

 

[supercorndogs]

I would be curious if the downward exhaust ports, which appear to above the feedlips of the magazine... might eventually Melt any plastic feedlips. ?

As for the dirty aspect... go to about 8:30 in the video.
I am not sure how much the filth would matter... unless you reloaded the same mag quite a few times.




And the Egg test....

Do most peopel not reload the magazine over and over? Surley most dont empty them and trash them.

 

[bfoosh006]

Do most peopel not reload the magazine over and over? Surley most dont empty them and trash them.

I'm sorry I should have been more specific....I meant if you were running and gunning or in a more combat related scenario , rather then sitting at the bench with the same mag all day.

And I posted all those video's .. not because I am sold on the idea. But more for others to see examples from KAK.

 

[antecedent]

I feel like it’d make more sense to cut a channel along the left side of receiver bore (shallow), put the carrier vents on that side in line with channel, stick a vent hole or two in the channel, and vent gas into a small, baffled manifold. Like an exhaust manifold/muffler thing.

I don’t know if there’s room, but maybe extend the area along the right side of the barrel extension a few mm to encourage gas at unlocking to head left as well.

Definitely not perfect, but seems like something you could retrofit to existing receivers, maybe?