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 42 users online :: 5 registered, 0 hidden and 37 guests


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

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Rifled barrel?

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

Rifled barrel?

Unread postAuthor: wyz2285 » Thu Dec 02, 2010 4:29 pm

Hi every body, a little question, is a rifled barrel really helps a lot on accurancy? I usually shot bbs, and it's easy to find rifled bb barrels. But I want to build bigger bore full metal sniper rifle, so just want to know if a rifled barrel makes a big difference. On my bb guns it looks no big difference :? and if it helps how can I rifle a metal barrel? My idea is make some thing simular to this :) http://www.spudfiles.com/forums/pneumat ... rt,15.html. The pic is the pellet I'm planing on
  • 0

Attachments
未命名.JPG
未命名.JPG (14.18 KiB) Viewed 1273 times
Last edited by wyz2285 on Sat Dec 04, 2010 4:39 pm, edited 1 time in total.
User avatar
wyz2285
Major General
Major General
 
Posts: 2244
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Country: Portugal (pt)
Reputation: 12

Unread postAuthor: jrrdw » Thu Dec 02, 2010 5:07 pm

You have to make a tool that fits the ID of your barrel with cutters protruding from it the depth of the rifling you want and pull it through your barrel to cut the grooves.
  • 0

When life gives you lemons...throw them back they suck!
User avatar
jrrdw
Donating Moderator
Donating Moderator
 
Posts: 6540
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Country: United States (us)
Reputation: 25

Unread postAuthor: saefroch » Thu Dec 02, 2010 5:33 pm

niglch wrote:In general, it was found that the rifled barrel had noticeably better accuracy as long as the projectile was snug and it's surface was something soft enough to be cut by the rifling.
That'd be why it doesn't make much of a difference on BB guns. The ammo needs to be soft, lead being the hardest material I've heard of working, or experience a massive acceleration and heat like on a conventional firearm or high-mix hybrid.

I know other people do it, but I'd like to congratulate you on digging up an old showcase post as example. That's what we always tell people and it's nice to see somebody do it. Grats! :)
  • 0

User avatar
saefroch
Major General
Major General
 
Posts: 1679
Joined: Mon Jun 08, 2009 8:47 am
Location: U.S.A.- See Map
Country: United States (us)
Reputation: 0

Unread postAuthor: Hubb » Fri Dec 03, 2010 7:57 am

Rifling a barrel for a spud gun is more for bragging rights than anything. I've done it on PVC and metal barrels, and I've honestly never seen a difference either way. We just don't use the ideal projectiles to take the best advantage of rifling.

Check the Hubb Library and download the barrel book. I've documented the rifling process (that most of us can do fairly easily) for plastic and metal barrels.
  • 0

User avatar
Hubb
Major General
Major General
 
Posts: 2390
Joined: Mon May 28, 2007 8:39 am
Location: South Georgia
Reputation: 2

Unread postAuthor: jackssmirkingrevenge » Fri Dec 03, 2010 8:14 am

Hubb wrote:Rifling a barrel for a spud gun is more for bragging rights than anything.


Agreed.

What projectiles did you plan on using?
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: wyz2285 » Fri Dec 03, 2010 12:08 pm

i'm going to use a 8mm dia barrel, and i will make some metal pellets with exactly the same dia. So the conclusion is it's not necessary to rifle a barrel? I know my projectile aren't soft, I'm looking for penetration power too
  • 0

User avatar
wyz2285
Major General
Major General
 
Posts: 2244
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Country: Portugal (pt)
Reputation: 12

Unread postAuthor: saefroch » Fri Dec 03, 2010 5:52 pm

wyz2285 wrote:So the conclusion is it's not necessary to rifle a barrel?
If you're not using something significantly soft, you won't notice any difference, and you'll have lots of scratches inside your nice barrel. Power won't (or shouldn't) suffer noticeably from rifling.

Personally, I'd get two barrels and rifle one, then see if you can find any ammo that'll take to the rifling.
  • 0

User avatar
saefroch
Major General
Major General
 
Posts: 1679
Joined: Mon Jun 08, 2009 8:47 am
Location: U.S.A.- See Map
Country: United States (us)
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: Hubb » Sat Dec 04, 2010 7:18 am

The rifling is not used for power, it's used for accuracy. If you want both out of a homemade launcher, your best bet would be to put a forward center of gravity (FCOG) on the round, much like a standard slug for a shotgun.

The option for a sabot in a rifled barrel exists, but this is much tedious work and you probably won't notice a performance increase by simply applying the FCOG round to the launcher.
  • 0

User avatar
Hubb
Major General
Major General
 
Posts: 2390
Joined: Mon May 28, 2007 8:39 am
Location: South Georgia
Reputation: 2

Unread postAuthor: wyz2285 » Sat Dec 04, 2010 8:25 am

I know a rifled barrel won't increase the power :) I'm looking for both power and accuracy. If the pellet has some rails on it to make it follow the rifle line will that help? But that would reduce the velocity of the pellet so do the power :(
  • 0

User avatar
wyz2285
Major General
Major General
 
Posts: 2244
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Country: Portugal (pt)
Reputation: 12

Unread postAuthor: Hubb » Sat Dec 04, 2010 11:22 am

Well, I guess, technically, you could put rails on a pellet to make it catch the rifling, but that's getting to a whole new meaning of the word "complicated." Just try the FCOG round. You won't be disappointed.

Oh, and if you are worried about a specific round reducing the velocity of the shot, compensate by turning up the pressure just a tad.
  • 0

User avatar
Hubb
Major General
Major General
 
Posts: 2390
Joined: Mon May 28, 2007 8:39 am
Location: South Georgia
Reputation: 2

Unread postAuthor: jackssmirkingrevenge » Sat Dec 04, 2010 11:29 am

Have a look at this test using Remington slugs which are simply lead slugs with a hollow base:

Image

A smoothbore barrel can give you very reasonable accuracy.
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: Hubb » Sat Dec 04, 2010 11:54 am

jackssmirkingrevenge wrote:Have a look at this test using Remington slugs which are simply lead slugs with a hollow base:
Funny. I just got done looking over that article just yesterday.
  • 0

User avatar
Hubb
Major General
Major General
 
Posts: 2390
Joined: Mon May 28, 2007 8:39 am
Location: South Georgia
Reputation: 2

Unread postAuthor: jackssmirkingrevenge » Sat Dec 04, 2010 12:05 pm

Hubb wrote:Funny. I just got done looking over that article just yesterday.


I usually link to it everytime the "is it worth rifling my barrel" discussion comes up :)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: wyz2285 » Sat Dec 04, 2010 12:09 pm

jackssmirkingrevenge wrote:
A smoothbore barrel can give you very reasonable accuracy.
thanks for the help :) now I can move on and make some test shots
Btw Hubb your article is great :P
  • 0

User avatar
wyz2285
Major General
Major General
 
Posts: 2244
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Country: Portugal (pt)
Reputation: 12

Unread postAuthor: Hubb » Sat Dec 04, 2010 12:43 pm

Share with us your thoughts on ammo now. How do you plan on applying this (in other words, if you need help, just ask)?
  • 0

User avatar
Hubb
Major General
Major General
 
Posts: 2390
Joined: Mon May 28, 2007 8:39 am
Location: South Georgia
Reputation: 2

Next

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Exabot [Bot], Google [Bot], Google Adsense [Bot], Yahoo [Bot]

Reputation System ©'