how small is too small for a barrel?

[JDP12]

hey all, i'm looking for a good quality barrel for my airsoft machine gun i'm making.

A 6mm airsoft bb is .236" in diameter, and i found aluminum tubing on mcmaster that is .2533" ID.

My only question is, is that too large to get a good accuracy rate from a vortex gun? Because with a brakeline barrel, accuracy is pretty crappy.

so i'm wondering if that's small enough to get good accuracy, or is it too small?

I mean will it be almost too small for the bb to ravel down easily?


Thanks

[DYI]

You can get seamless SS tubing on McMaster in .243", which should be an excellent bore size.

[JDP12]

oh cool thanks DYI

[MrCrowley]

I'm pretty sure 6mm BB's aren't exactly 6mm. Last I checked with my digital calipers they were about 5.87mm which is closer to .231".

[OuchProgramme]

Since this is an airsoft machine gun, MORE than one of the 50 persecond BB's that you'll be shooting will most likely hit the target.

[JDP12]

true.. but i still want a tight-as-possible "beam" of bb's.

[Eddbot]

I was checking out McMaster, and when searching for tubing i noticed i could change the measurements to metric, so i chose 6mm, got these 50365K321
50365K322 same pipe, the first is half a meter, second is a whole meter

[Hotwired]

Regarding the title, my personal smallest barrel is 3mm ID

Can still pop a hole through 1/2" planks

[rcman50166]

I would buy one if you really need good quality. Try a tight bore airsoft barrel. Here's a good site I found with a quick google. http://www.madbullairsoft.com/English/i ... ex&cPath=7 They typically are around 6.03 mm diameter. Pretty damn close. BB's fit so nicely, unpolished bb's will jam in the barrel.

[Ragnarok]

Like MrC said, they're usually a little under 6mm. I normally get from 5.95mm to 5.98mm, not as small has he does, but still just under 6mm.

In my opinion, for a vortex, a tight bore barrel is probably a poor idea, given that the feed is a little... vigorous, so there needs to be some gap for it to work reliably, though Neospud/MrPlow has done it with a Madbull barrel I believe.

A fairly tight barrel is however a smart idea, because it will improve muzzle velocity, reduce gas use slightly, and be a little more accurate.

In an ideal world, a barrel would have moderately wide breech end, maybe 6.4-6.5mm, which is then quickly choked down to about 6.1mm. Because the vortex might damage pellets, it's unwise to go as fine as 6.03, as jamming might occur. Not too often, perhaps once in thousands of pellets, but if you occasionally use low(er) quality pellets, it might.

.243" ID tubing should be decent for all those purposes, as the gap would be around 0.2mm, not too large.

[OuchProgramme]

Well you could flare out the recieving end

[ammosmoke]

Well you could flare out the recieving end

Wouldn't doing so damage the barrel below where you have flared it out? And wouldn't this harm your accuracy? Because, if you shove a nail punch or something in there and ram it, it will cause creases. Or, if you use a dremel you will have metal shavings to clean, and an abrupt edge for the bb's to travel over. I would just get the barrel with a lower tolarance and call it good. The first one, as Ragnarok said, would probably be a good idea.

[Velocity]

I bought a very nice 6mm steel barrel...but it was too tight for the crappy cheap yellow 0.12g airsoft BB's...you think if I upgraded to nicer ones, they would fit in the barrel?

[TurboSuper]

I used some brake-line tubing for mine. Works perfectly.

[OuchProgramme]

Well you could flare out the recieving end

Wouldn't doing so damage the barrel below where you have flared it out? And wouldn't this harm your accuracy? Because, if you shove a nail punch or something in there and ram it, it will cause creases. Or, if you use a dremel you will have metal shavings to clean, and an abrupt edge for the bb's to travel over. I would just get the barrel with a lower tolarance and call it good. The first one, as Ragnarok said, would probably be a good idea.

Wow..thats not how you flare out a barrel lol...

No it wouldn't harm you accuracy
Its the RECIEVING end...
flaring a pipe isn't putting a dremel through it