madbull/echo1usa special tightbore project ... ?what in the

[Skywalker]

World. What in the world.

Ok while working on a gearbox of a gun, I've stumbled upon a barrel with holes (professionally) drilled through it, labeled "madbull/echo1usa special tightbore barrel project".

Its m4 length, with 5 holes drilled through it aproximently 2 inches from the hop up unit. About 1/8th inch in diameter. Then another inch and a half down the barrel there are 2 rectangular cut outs, same diameter, about 3/8ths long. All of the holes go through both sides of the barrel.

Any ideas as to what in the world this is? ??

There is a storm over my house right now, so the internet on my computer isn't working. And I don't really want to go through the trouble of posting pictures from my phone. I will post them later when the computer works again.

[Skywalker]

I understand the theory of porting the barrel... but why on a m4 gun with a stock gearbox? (It should already be set up for a good volume ratio)

The second question would be, does any air really even escape, since the inner barrel is snug inside the outer barrel...?

I figure someone just didn't know what they were doing, but why is this product even produced? And.... why doesn't it show up on google when I search for it? Lol

[Dominum]

Why would they port it near the hopup unit? This is indeed interesting, now I want to see it. If I can think of something probable I will share, but until then I will just be scratching my head.

[Hotspur93]

How did you acquire the gun?

[Skywalker]

Im working on it for somebody else. It wasn't working, but it was a simple electrical fix

[SteevoLS]

BWAHAHAHAA!

I know something you don't know.

I mean, wow... these things have been around for years.

This is a Madbull Crawler barrel. Those ports are meant specifically to bleed off air to lower the FPS. For example, you could have a M120 gearbox built to perfection, and simply drop in a different barrel/hopup assembly and use it for CQB.

[Skywalker]

Hmm ok that makes sense I guess... that is, if air can escape between the inner and outer barrel.

And why is it a madbull/echo1 product? That seems really weird to me

[SteevoLS]

Probably for the same reason that Classic Army Sportlines are Gameface "products".

They certainly work, but the most you'll lose is about 100 FPS. I saw a few chrono videos a while back where the guns were only losing 30-50 FPS.

[Hotspur93]

Well 30-50 could be all the difference in FPS that some one would need to go from field to CQB

[Dominum]

Well then, that makes sense. I was trying to think of how they could do that without losing a lot of FPS, especially being ported further back when there is still a lot of pressure. I guess if you want to lose FPS, then that is the way to do it! I learned something today. The more you know!