8 replies to this topic

[cerealkiller]

Here it goes with another of my stories:

Ok so my friend (who is really crazy and wants to go to Israel to become a SWAT member there) is brassing his NF. I give him a 6 in 9/16 bass and he jammes it, in literally, but at the bottom of the barrel, sticks a dead dart with a straw in the middle, and covering the side with lots of electrical tape so it wont blow out.

My question is if he does that, will it be better? If the air has to go through a smaller passage, like the straw, will it be better for the gun? I couldn't really tell with his NF, it looked the same.

Another thing is that he says that there is virually no friction when the dart or bullet flies through the barrel, so the longer the barrel, the better. Hey says since there is only one way the air can go, so it just keeps building up. I don't really think that's necessarily true, I'm sure there comes a point that friction will decrease its range. Think about it. When you feel the air right next to the releasing valve, its stronger that when you feel it with the end of a barrel attached on to it.

Edited by cerealkiller, 06 January 2005 - 01:44 AM.

[taita cakes]

Considering he is only ramming in the brass barrel, i'd have to say there wouldn't be too much of an improvement. Barrel's need to be sealed well.

[okto]

Is he Jewish? Or Israeli? They don't allow foreigners in their military forces.

[J cobbers]

Air under pressure works something like a conpressed spring, when released it will press against the dart until it reaches the same pressure as the air out side. Basically this means that as long as the volume of the barrel is not greater than the volume of the air used to fire the dart a longer barrel will provide greater acceleration. I have made barrels for guns that were too long to fire a dart, because the dart travels so far down that the air used to fire it equals less than the volume of the distance traveled down the barrel and a small vaccum formed, slowing the dart down along with friction.

Of course the barrel material matters; in higher friction materials like cpvc and pvc a dart will start to slow down when the pressure acting as a force behind the dart is less than the force needed to over come the friction between dart and barrel.

Brass and PTEG offer much lower friction on the darts and are more ideal for longer barrels.

[Fuse]

Is he Jewish? Or Israeli? They don't allow foreigners in their military forces.

Well I also seriously doubt they have SWAT teams, since that acronym is english.

[Drano]

CK, he wants to go back to Malayasia to serve on thier "swat". Cobbers is right the straw probabbly served as a barrel constriction.

Fuse, Israel does indeed have special weapons and tactics teams, they probabbly just dont call them "SWAT" I read something about a national SWAT competition held in Texas or Tennessee or something. Israel, Germany and some other countries were invited.

[rusty]

I read something about a national SWAT competition held in Texas or Tennessee or something. Israel, Germany and some other countries were invited.

Wouldn't that be international?

The straw inside the barrel would act like a bottleneck, and I think increase the pressure. If I'm right then he's elminited the need for tighter barrels in spring guns. We use tighter barrels in spring guns so that the dart doesn't start to move, and therefore pressure builds up behind the dart causing the dart to go farther. With the straw, the bottleneck does the job that would normally be done by a tighter barrel.

[Techno-Dann]

Erm... Air pressure goes up a little bit, but most of what happens with a setup like that is that the amount of air coming through the barrel is cut. All the mod really does is restrict the flow, thus giving less pressure on the dart side of the barrier, and thus giving less dart velocity and range. Why do you think we tear out the flow restrictors in stock guns?

Yeah. It's an interesting idea, but conceptually, I don't think it works.

[cxwq]

All the mod really does is restrict the flow, thus giving less pressure on the dart side of the barrier, and thus giving less dart velocity and range.

Bingo.