Copper spudgun

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
User avatar
wyz2285
First Sergeant 2
First Sergeant 2
Austria
Posts: 2385
Joined: Sat Mar 06, 2010 7:50 am
Location: Porto, Portugal
Has thanked: 1 time
Been thanked: 3 times
Contact:

Mon May 17, 2010 3:17 pm

you need a better barrel,and a scope,it helps a lot.
User avatar
Biopyro
Corporal 2
Corporal 2
Posts: 654
Joined: Fri Aug 04, 2006 5:32 am
Location: UK

Mon May 17, 2010 4:39 pm

Define "better barrel"?
That's not great accuracy at all.
I suspect the high power is causing destabilising muzzle blast, so perhaps consider a muzzle brake or suppressor style holes in the end of the barrel* to vent the fast moving gas after the projectile is moving. This will hopefully prevent the projectile tumbling too much/ being knocked off course.
A longer barrel would help too, but maybe a tank style break would give the same accuracy without the length.


*I'm sad that I don't remember what this is called, it's been too long :(
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety. -Benjamin Franklin
User avatar
Lockednloaded
Staff Sergeant
Staff Sergeant
United States of America
Posts: 1566
Joined: Thu Sep 03, 2009 9:38 pm
Location: Texas, USA
Been thanked: 6 times

Mon May 17, 2010 5:59 pm

Biopyro, i think they are called "barrel ports" but not sure. Is muzzle blast interference really a huge issue? at what point does it begin to throw off accuracy?
I love lamp
User avatar
Patto
Private 4
Private 4
Posts: 96
Joined: Wed Jan 20, 2010 7:08 pm

Mon May 17, 2010 9:23 pm

nice build man :D

I'd try changing your projectile ?? maybe steel balls ?
smooth bore @ 100psi you should be able to hit consistently 10 - 15m :lol: mine does well over 12m at least 4/5 keep it up and good luck
User avatar
Biopyro
Corporal 2
Corporal 2
Posts: 654
Joined: Fri Aug 04, 2006 5:32 am
Location: UK

Tue May 18, 2010 2:07 am

Lockednloaded wrote:Biopyro, i think they are called "barrel ports" but not sure. Is muzzle blast interference really a huge issue? at what point does it begin to throw off accuracy?
Yes I think you're right there, thanks.

It's hard to define a point when it happens exactly, but it becomes more likely as the C:B ratio decreases (currently quite low at 0.54) and as the pressure increases (100psi is not unreasonable), so I would put it down to the C:B.
Now I've done the calculation I'm pretty sure that some barrel ports would go a long way here.
Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety. -Benjamin Franklin
User avatar
Labtecpower
Sergeant 3
Sergeant 3
Eritrea
Posts: 1297
Joined: Sat Feb 20, 2010 6:38 am
Location: Pyongyang
Has thanked: 5 times
Been thanked: 13 times

Tue May 18, 2010 1:58 pm

I added a muzzle brake today. I have the idea that it improved accuracy a small bit.
The only bad thing is that the holes in my muzzle brake is shredding my paper wadding into a sort of confetti cloud :D .
I made some iron sights, this improved accuracy very very much.
Without sights I sometimes missed the back stop ( :shock: ), but now I can hit the back of a tin from 10 meters away.

Edit: typo's :evil:
Post Reply