MB2 - edit : second edition

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
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Wed Oct 11, 2006 4:32 pm

MB2 (Marble Blaster II)

[albumimg]233[/albumimg]

Here it is, my second pneumatic gun, only two weeks after I finished the first one :

* as I sead, it is pneumatic
* made fully out of metal (copper)
* uses barrel sealing piston valve
* pilote valve triggered by a 3/4 balvalve
* dual chamber 34 mm copper pipe
* rest of the gun is made at 28 mm copper pipes and pices
* pressurizing valve is a bycicle tire valve
* C:B ratio, depends on the barrel type, at least 2:1 with the 34 mm barrel
* it has exchangable barrels, 10 mm, 15 mm, 18 mm, 22 mm, 28 mm, 34 mm and a 1 inch galva barrel

[albumimg]234[/albumimg]

Ammo : about everything I can lay my hand on :twisted:
For starters I use marbles, both small ones (16 mm) and big ones (26 mm)

I testfired it, and it leaked at the piston valve. So I changed the rubber, nog it is ok. I could only testfire it at 100 psi, dont have more pressure untill my high pressure pump is ready.

Here the damage pics :

[albumimg]236[/albumimg] [albumimg]237[/albumimg]

and a pic of the actual test fire ammo

[albumimg]235[/albumimg]

Me holding the gun, so you can see the size :

[albumimg]238[/albumimg]

Improvements since the MB1 :

* shorther space between the piston valve and the ammo
* bigger chamber
* better piston
* ighter than a galva gun

What still needs to be done :

* make a wooden stock
* make a wooden handgrip in front
* give the whole thing a paintjob (will be non-shining black)


Now some questions :

What about this gun, you like it ?
What can I do to improve ?
At what pressure you think I can shoot this one ?
Do you like the concept of the twin chamber in this gun ?

Edit : forgot to mention the cost : about 100 euro.
Last edited by POS on Tue Oct 17, 2006 3:28 pm, edited 5 times in total.
Mr.Taterhead
Private 2
Private 2
Posts: 34
Joined: Sat Sep 23, 2006 8:51 pm
Location: London KY

Wed Oct 11, 2006 5:09 pm

:D I like it man and I love the ammo. What kind if rubber are you useing for the barrel seal ??
User avatar
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Wed Oct 11, 2006 5:16 pm

rubber from a bycicle tire :)

The inner tire that is
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Wed Oct 11, 2006 9:03 pm

wow nice copper gun,if you put a wooden hand grip on you should get that grip paper stuff that you find on rifle stocks at the front :twisted:
User avatar
rna_duelers
Staff Sergeant 3
Staff Sergeant 3
Posts: 1739
Joined: Mon Sep 26, 2005 7:07 am
Location: G-land Australia

Thu Oct 12, 2006 1:28 am

Nice,but the pics are a little small to see the in good detail.And yes i like the twin chamber and i wouldnt be afraid to take it to 250psi 17bar.
Image
User avatar
killagorrila99
Sergeant 2
Sergeant 2
Posts: 1100
Joined: Tue Jul 25, 2006 2:35 am
Location: Australia.

Thu Oct 12, 2006 7:23 am

Thats why you click on the pictures.!!! loverly gun ya got there, any idea on distance?
"I'm sorry, Mr.Bush cant come to the phone right now, He's playing cleudo with Mr. Cheney And he has him in the Cupboard with a broom stick" -White house receptionist.
User avatar
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Thu Oct 12, 2006 4:25 pm

Haven't tried distance yet. I live in the woods. Lots of trees here ;)
User avatar
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Tue Oct 17, 2006 12:14 pm

Ok, the gun is completely finished now. Got some pics and damagepics, enjoy :
Attachments
Backside of the second wooden plate. Damage mainly caused by the third shot
Backside of the second wooden plate. Damage mainly caused by the third shot
the damage at the second plate. Notice the difference due to the use of (different) wadding behind the marble
the damage at the second plate. Notice the difference due to the use of (different) wadding behind the marble
I testfired three times at a thin wooden plate (4 mm) and a thicker plate (2 cm). Here the dammage at the first thin plate, nice round holes of 25 mm :)
I testfired three times at a thin wooden plate (4 mm) and a thicker plate (2 cm). Here the dammage at the first thin plate, nice round holes of 25 mm :)
Me and the gun, to give you an idea how big it is. It holds very confortable, notice here the bipod is unmounted
Me and the gun, to give you an idea how big it is. It holds very confortable, notice here the bipod is unmounted
All the barrels I have right now. Notice the second barrel from the bottom, is a recycle of my MB1. these barrels are 15 mm, 18 mm, 22 mm, 28 mm, and a 1" galva dirt blaster
All the barrels I have right now. Notice the second barrel from the bottom, is a recycle of my MB1. these barrels are 15 mm, 18 mm, 22 mm, 28 mm, and a 1" galva dirt blaster
Closup of the stock. This is made of 4 mm thick steel, heated, twisted, hammered and welded.
Closup of the stock. This is made of 4 mm thick steel, heated, twisted, hammered and welded.
The gun with the "shot gun " barrel, shoots big marbles of 25 mm.
The gun with the "shot gun " barrel, shoots big marbles of 25 mm.
The gun "naked" gun without a barrel, sprayed black and equiped with a steel stock
The gun "naked" gun without a barrel, sprayed black and equiped with a steel stock
User avatar
CpTn_lAw
Corporal 5
Corporal 5
Posts: 987
Joined: Sun Sep 11, 2005 9:10 am
Location: France

Tue Oct 17, 2006 12:22 pm

this .....is............mmh.......AWESOME!!!!!!!!!!!!!!!!!!!!!
User avatar
Brian the brain
Moderator
Moderator
Netherlands
Posts: 3497
Joined: Mon Dec 05, 2005 2:06 am
Location: Holland
Been thanked: 7 times

Tue Oct 17, 2006 12:31 pm

mm where did you get those 34 ( I think it should be 35??) fittings and pipe??


If I could get that I would defenitely redo the old sawed-off in 35 mm!!!!
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
User avatar
)DEMON(
Sergeant 4
Sergeant 4
Posts: 1391
Joined: Sun Mar 12, 2006 1:22 pm
Location: Johannesburg South Africa

Tue Oct 17, 2006 2:11 pm

Man!, that is really cool! I really love the stock, it gives the cannon such a threatening yet awsome look. :D
I think you should try make that as tough as possible, by renfocing the chambers. Great work :D
Forever dreaming...
User avatar
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Tue Oct 17, 2006 2:48 pm

Brian the brain wrote:mm where did you get those 34 ( I think it should be 35??) fittings and pipe??


If I could get that I would definitly redo the old sawed-off in 35 mm!!!!
I only fount it in 1 do-it-yourself-shop. It is 34 mm indeed. I bought reducer parts, from 34 to 28. At least I tought so. It was actualy 35 to 28 mm. So they didn't fit. I had to made them fit. I couldn't find endcaps eighter, so that's why there are reducer parts in the frontside of the chamber. The twe chambers are solderen together in front, but not connected like air-wise. The chambers are pretty stong, no wories about that

The stock is very strong to. I had much problems and had to work really hard to get the steel in this form.

I just tried a distance shot. I put up a target, a wooden plate (the second plate in the above pics) up to 25 meter, halfway my driveway. In front of it, I put the first plate from the pics above. I lied down at the door of the house, aimed for the top of the plate, cause the bullet always drop in his flight (I used a 25 mm marble) and shot the target at 8 bar. (110 psi) I didn't even hit teh first plate. The bullet only dropped a couple of centimeters, hitting directly on the second plate, en flew clear trough (nice round hole, and major damage on the backside. After I heard it hitting the wood, I heard a 'ting'-noice. The bullet flex further of course, hitting the steel gate. I went out to see if the gate was dammages, and unfortunaly it was. One of the vertical steel pipes had a dent in it. The gate was 50 meters away from the gun.

I was very pleased whit this performance 8)

Now I just need some sort of sight to get a bether aim.
Last edited by POS on Wed Feb 18, 2009 3:45 pm, edited 1 time in total.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Tue Oct 17, 2006 2:58 pm

wow that looks sweet :!: nice damage pics and i like what you did with the stock, is that a first in the spud-gunning world?
User avatar
POS
Specialist 3
Specialist 3
Posts: 395
Joined: Thu Sep 14, 2006 4:19 pm

Tue Oct 17, 2006 3:14 pm

Dont know, would be niuce though.

Got a question about the GGDT. The weight of the projectile is in "gm" What on earth is that ? I know mg (milligram), but that sure aint'it.

And does someone know the weight of a 25 mm marble ?
User avatar
killagorrila99
Sergeant 2
Sergeant 2
Posts: 1100
Joined: Tue Jul 25, 2006 2:35 am
Location: Australia.

Wed Oct 18, 2006 1:14 am

Brian the brain wrote:mm where did you get those 34 ( I think it should be 35??) fittings and pipe??


If I could get that I would defenitely redo the old sawed-off in 35 mm!!!!



I can get 32mm Pipe, Thats what I used on the chamber for Heavy Artillery and the now compleated Hunting rifle.
"I'm sorry, Mr.Bush cant come to the phone right now, He's playing cleudo with Mr. Cheney And he has him in the Cupboard with a broom stick" -White house receptionist.
Post Reply