Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 55 users online :: 4 registered, 0 hidden and 51 guests


Most users ever online was 218 on Wed Dec 07, 2016 6:58 pm

Registered users: Alexa [Bot], Google [Bot], Majestic-12 [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

how small is too small for a barrel?

Post about things you have launched or thought about launching. Also post about various materials used for building cannons. No posts about explosive projectiles!
Sponsored 
  • Author
    Message

how small is too small for a barrel?

Unread postAuthor: JDP12 » Sat May 17, 2008 10:07 pm

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
  • 0

"Some say his pet elephant is pink, and that he has no understanding of "PG rated forum". All we know is, he's called JSR. "
User avatar
JDP12
Major General
Major General
 
Posts: 1943
Joined: Fri Mar 30, 2007 8:34 pm
Reputation: 0

Unread postAuthor: DYI » Sat May 17, 2008 10:09 pm

You can get seamless SS tubing on McMaster in .243", which should be an excellent bore size.
  • 0

Spudfiles' resident expert on all things that sail through the air at improbable speeds, trailing an incandescent wake of ionized air, dissociated polymers and metal oxides.
User avatar
DYI
Lieutenant General
Lieutenant General
 
Posts: 2861
Joined: Sat Jul 07, 2007 8:18 pm
Location: The People's Republic of Canuckistan
Country: Turks and Caicos Islands (tc)
Reputation: 9

Unread postAuthor: JDP12 » Sat May 17, 2008 10:10 pm

oh cool thanks DYI
  • 0

"Some say his pet elephant is pink, and that he has no understanding of "PG rated forum". All we know is, he's called JSR. "
User avatar
JDP12
Major General
Major General
 
Posts: 1943
Joined: Fri Mar 30, 2007 8:34 pm
Reputation: 0

Unread postAuthor: MrCrowley » Sat May 17, 2008 10:16 pm

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".
  • 0

User avatar
MrCrowley
Moderator
Moderator
 
Posts: 10207
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Country: New Zealand (nz)
Reputation: 4

Unread postAuthor: OuchProgramme » Sat May 17, 2008 10:17 pm

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.
  • 0


OuchProgramme
Major
Major
 
Posts: 371
Joined: Sat Jan 12, 2008 7:30 pm
Reputation: 0

Unread postAuthor: JDP12 » Sat May 17, 2008 10:29 pm

true.. but i still want a tight-as-possible "beam" of bb's.
  • 0

"Some say his pet elephant is pink, and that he has no understanding of "PG rated forum". All we know is, he's called JSR. "
User avatar
JDP12
Major General
Major General
 
Posts: 1943
Joined: Fri Mar 30, 2007 8:34 pm
Reputation: 0

Unread postAuthor: Eddbot » Sat May 17, 2008 10:31 pm

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
  • 0

:edfirst:
User avatar
Eddbot
Lieutenant Colonel
Lieutenant Colonel
 
Posts: 434
Joined: Tue Oct 09, 2007 6:08 pm
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: Hotwired » Mon May 19, 2008 11:20 am

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

Can still pop a hole through 1/2" planks :)
  • 0

User avatar
Hotwired
Lieutenant General
Lieutenant General
 
Posts: 2599
Joined: Fri Oct 13, 2006 5:51 am
Location: UK
Reputation: 0

Unread postAuthor: rcman50166 » Mon May 19, 2008 11:32 am

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/index.php?main_page=index&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.
  • 0

Image
User avatar
rcman50166
Colonel
Colonel
 
Posts: 697
Joined: Sat Jan 19, 2008 7:11 pm
Location: Bethel, CT
Reputation: 0

Unread postAuthor: Ragnarok » Mon May 19, 2008 12:22 pm

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.
  • 0

Does that thing kinda look like a big cat to you?
User avatar
Ragnarok
Chief of Staff
Chief of Staff
 
Posts: 5339
Joined: Tue Dec 19, 2006 8:23 am
Location: The UK
Reputation: 8

Unread postAuthor: OuchProgramme » Tue May 20, 2008 5:46 pm

Well you could flare out the recieving end
  • 0


OuchProgramme
Major
Major
 
Posts: 371
Joined: Sat Jan 12, 2008 7:30 pm
Reputation: 0

Unread postAuthor: ammosmoke » Tue May 20, 2008 7:54 pm

OuchProgramme wrote: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.
  • 0

<img>http://www.speedtest.net/result/309559995.png</img>
User avatar
ammosmoke
Brigadier General
Brigadier General
 
Posts: 1011
Joined: Wed Sep 27, 2006 10:57 am
Reputation: 0

Unread postAuthor: Velocity » Tue May 20, 2008 8:06 pm

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?
  • 0

User avatar
Velocity
Brigadier General
Brigadier General
 
Posts: 1039
Joined: Tue Feb 07, 2006 5:42 pm
Reputation: 0

Unread postAuthor: TurboSuper » Tue May 20, 2008 9:09 pm

I used some brake-line tubing for mine. Works perfectly.
  • 0

"If at first you dont succeed, then skydiving is not for you" - Darwin Awards

TurboSuper
Brigadier General
Brigadier General
 
Posts: 986
Joined: Thu Jun 16, 2005 1:44 pm
Reputation: 0

Unread postAuthor: OuchProgramme » Tue May 20, 2008 9:35 pm

ammosmoke wrote:
OuchProgramme wrote: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
  • 0


OuchProgramme
Major
Major
 
Posts: 371
Joined: Sat Jan 12, 2008 7:30 pm
Reputation: 0

Return to Construction Materials/Ammo Discussion

Who is online

Registered users: Alexa [Bot], Google [Bot], Majestic-12 [Bot], Yahoo [Bot]

Reputation System ©'