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 54 users online :: 5 registered, 0 hidden and 49 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

hop-up

This area is for the discussion of BB or airsoft sub machine guns, and or other small arms such as pellets.
Sponsored 
  • Author
    Message

hop-up

Unread postAuthor: ALIHISGREAT » Fri Oct 19, 2007 5:04 pm

would putting a line of small holes along the top of my barrel put backspin on a bb, the holes would probably be around 1cm or less apart and would be in the last 20cm of the 80cm long barrel.
  • 0

User avatar
ALIHISGREAT
Major General
Major General
 
Posts: 1779
Joined: Sat Aug 25, 2007 6:47 pm
Location: UK
Reputation: 0

Unread postAuthor: e1337 » Fri Oct 19, 2007 5:10 pm

I really don't know, I think it would due to drag, but you might lose power.

Peace,
e1337
  • 0


e1337
Staff Sergeant
Staff Sergeant
 
Posts: 110
Joined: Mon May 28, 2007 8:00 pm
Location: Florida
Reputation: 0

Unread postAuthor: Hubb » Fri Oct 19, 2007 5:36 pm

I've thought about this, too (only for paintball). The best way I've figured it would be to put a small laceration into the top of the barrel, near the breech. Then obtain o-rings to fit in these slits and place the o-ring in such a way so that part of the o-ring is actually in the barrel. I've included a diagram to help better understand it.
  • 0

Attachments
untitled.jpg
This is actually not my idea. A discussion came up a while back about it. I just incorporated it for use.
untitled.jpg (9.01 KiB) Viewed 1641 times
User avatar
Hubb
Major General
Major General
 
Posts: 2390
Joined: Mon May 28, 2007 8:39 am
Location: South Georgia
Reputation: 2

Unread postAuthor: ALIHISGREAT » Fri Oct 19, 2007 5:43 pm

so that would work because of friction between the bb and the o-rings? so the o-rings would wear over time.
  • 0

User avatar
ALIHISGREAT
Major General
Major General
 
Posts: 1779
Joined: Sat Aug 25, 2007 6:47 pm
Location: UK
Reputation: 0

Unread postAuthor: Hubb » Fri Oct 19, 2007 5:50 pm

The o-rings probably would wear over time, which is why the o-rings should be replaceable.
  • 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: ALIHISGREAT » Fri Oct 19, 2007 5:59 pm

hmm could get fiddley in a 6mm barrel, i would prefer using my idea (if it works) because it would act as a silencer too because my barrel will be inside some 15mm pipe.
  • 0

User avatar
ALIHISGREAT
Major General
Major General
 
Posts: 1779
Joined: Sat Aug 25, 2007 6:47 pm
Location: UK
Reputation: 0

Unread postAuthor: Hubb » Fri Oct 19, 2007 6:22 pm

Yeah, it may be hard to accomplish using that size barrel. However, your idea seems more like normal porting. I don't know how effective it's going to be in creating hop-up. It may work, but I don't know.
  • 0

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

Sponsored

Sponsor
 


Unread postAuthor: Marco321 » Fri Oct 19, 2007 7:34 pm

Just put a trin strip of rubber at the top of the barrel, it will create backspin, thats how its done in airsoft i believe.
  • 0

Failure to plan is planning to fail.

The 7 P's - Proper Prior Preparation Prevents Piss Poor Performance
User avatar
Marco321
Colonel
Colonel
 
Posts: 540
Joined: Tue May 15, 2007 2:56 am
Location: Sydney, Australia
Reputation: 0

Unread postAuthor: noname » Fri Oct 19, 2007 10:42 pm

Your idea will most likely not work, and drilling small holes in small diameter metal pipe is a [female doggy]. All you need to is cut a tiny slot in the end of your barrel (perpendicular to end of barrel, about 1 cm from the end) and put an O-ring in it. It works great, and replacement O-ringas are only like $0.10 at that size.
  • 0

User avatar
noname
Lieutenant General
Lieutenant General
 
Posts: 2699
Joined: Mon Apr 10, 2006 9:19 pm
Location: Bay Area, CA
Country: United States (us)
Reputation: 9

Unread postAuthor: ALIHISGREAT » Sat Oct 20, 2007 3:23 am

noname wrote:Your idea will most likely not work, and drilling small holes in small diameter metal pipe is a [female doggy]. All you need to is cut a tiny slot in the end of your barrel (perpendicular to end of barrel, about 1 cm from the end) and put an O-ring in it. It works great, and replacement O-ringas are only like $0.10 at that size.


well i'm gonna be drilling holes anyway becasue i'm gonna suppress it so i was just wondering if the postition of the holes affected the spin on the bb.

and if i was to put a strip of rubber along the top of my barrel how long would it need to be and if the barrel was a tight fit would tape work?
  • 0

User avatar
ALIHISGREAT
Major General
Major General
 
Posts: 1779
Joined: Sat Aug 25, 2007 6:47 pm
Location: UK
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sat Oct 20, 2007 3:55 am

Why bother with hopup slowing the BBs down when you could just aim higher?
  • 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: ALIHISGREAT » Sat Oct 20, 2007 4:04 am

jackssmirkingrevenge wrote:Why bother with hopup slowing the BBs down when you could just aim higher?


it would make the gun more accurate because it would counteract any spin put on the bb becasue of imperfections in the barrel.

although i could just use a tissue sabot to do this.

however i will be drilling holes anyway so i thought that they could have a second use.
  • 0

User avatar
ALIHISGREAT
Major General
Major General
 
Posts: 1779
Joined: Sat Aug 25, 2007 6:47 pm
Location: UK
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sat Oct 20, 2007 4:11 am

it would make the gun more accurate because it would counteract any spin put on the bb becasue of


Would it?

As far as I know, the whole point of hop-up is to give BBs an upwards spin in order to flatter the trajectory, to compensate for projectile drop which is more evident in BBs due to their very poor ballistic co-efficient. Since you'll be firing "heavyweight" BBs at much higher velocities than normal BB guns, I wouldn't bother.

imperfections in the barrel


What on earth are you using for a barrel then? Sheep intestines? :D
  • 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: ALIHISGREAT » Sat Oct 20, 2007 4:44 am

no... not sheep intestines aluminium tube but there will probably be imperfections becasue its not designed to be super smooth and perfect i assume although i'll have a look later when i buy it, and i want hop up to give awsome range and accuracy.

no one has answered my qustion though, would the porting along the top of the barrel put backspin on the bb or not?
  • 0

User avatar
ALIHISGREAT
Major General
Major General
 
Posts: 1779
Joined: Sat Aug 25, 2007 6:47 pm
Location: UK
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sat Oct 20, 2007 4:49 am

i want hop up to give awsome range and accuracy


Chances are that without adjustable hop-up, you're never going to be able to tweak it to get that - I say stick to no hop-up and make a range table to compensate for BB drop.

I wouldn't worry about imperfections - I don't know what sort of tubing you're buying but the ali tube I've found has always been perfectly smooth on the inside.
  • 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

Next

Return to BB/Airsoft/Pellet Gun Discussion

Who is online

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

Reputation System ©'