Instructables

Spring powered BB Gun

This is a project i am currently working on - spring powered BB/Dart gun. Requires Spring, Metal/PVC pipe (Whichever you feel more secure with, i chose metal), Metal barrel, I chose 4.5mm .77 barrel from an old airgun, spring, some cutting of wood, and dowwel. This is alot more powerful than other bb guns powered by combustion, bike pumps ect. so be carefull.
 
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Step 1: Materials

Airgun Spring - Check your local airgun shop, or if your australian, find one.

Wooden circles, cut with a hole saw

Metal tubing, to fit your spring.

Endcap for the tubing

4.5mm copper, or any other metal tubing for barrel, 4.5mm is .177 for metal bb's or airgun darts, although if you wanted to fire plastic bb's you will need 6mm tubing i think.

Metal dowwel

I think thats it *thinking face*


Step 2: First step (not really step two)

See picture, you only cut into one side of the piping, dont go all the way through

Step 3: Step Two

Add your spring to the tube

Step 4: Step Three

Now, put a holesaw on your drill with 4mm drill bit in and whatever holesaw bit you need to fit your spring tube, it has to be able to move in there, if need be file it down a bit if you dont have the right drill bit.

Then, throught the hole in the middle, glue the 4mm dowweling in.
Screw a screw in the top of your circle, the slide the screw down your cutting in the springtube, therefore compressing the spring, and then twist to the side, locking in place, this is how you cock your gun.
Put this in your spring tube.

Step 5: Step 4

Now copy step three, but put a 4.5mm drill bit in your drill with a little larger holesaw bit, this shouldnt move in the spring tube. drill your circle out.

INstead of dowweling use 4.5mm (hollow!) copper/metal pipe do not block it off at all, this is your barrel

Glue the hole thing onto the other end of your tube, like an endcap. all done:)
indiana_j lol9 months ago
Where is the trigger?

How big does the spring have to be

it has no trigger you just pull back and let go............

bigman1232 years ago
cool gun ! where is the triger
sabladask3 years ago
Good! see my instructable i made a springpowerd piston airgun.
Surefire1233 years ago
Sorry Scoblania but momentum is not force x time that's impulse which is the change in momentum over time. Momentum is Mass x Velocity. So you need to increase the impulse of the ammo.
scoblaina4 years ago
i really do like this design, and currently using three really strong springs 9cm by 3.5 (bought in bunnings, yes im aussie) and so yeah its pretty big, but while it has immense power, shoots really badly (using thick nails cut in half and so are about 3.5 cm long, they should be solid enough yet aerodynamic enough so i dont think its the ammo) anyway i think the trouble is that its not providing enough momentum, as the steel rod only pushes the nail about 15cm, before the nail relies on its own momentum. Because change in momentum=force x change in time, i think that the rod should push the nail for a lot alot longer (maybe even 50 cm), so is in contact with nail for longer, but this means a lot more springs which means the whole thing has to be bigger (think of how far you pull back a slingshot), so i recomend if having a fairly big powerful design make sure the rod is long, i will keep working on this and let you know what happens
Go Australia! Go Bunnings!
Has anyone actually made this? If not I have a few ideas obviously majority credit going to Camster911 but I'll think of a design!!!! Using a BIC Pen and a BIC Lighter!
scoblaina4 years ago
yeah it should be pretty good and il work on the ammo problem. il probs have it finished in about 3-5 weeks when i have more time and il keep this page posted when im done with links n stuff, it should be pretty big though
owen954 years ago
thats cool cant wait to try it.    but first up scoblaina the nail is not the right sorta ammo to be shooting , a pellet or bb is much smaller and lighterand a bb ofers better acuresy then a nail "out of a smooth bore"

but yeah i cant wait to try it hope u dont mind me tryin to modify ur disign to go in a stock with a trigger.
JACK_MAN644 years ago
hey umm yer im with smily face im an ausse so how the hell do i find one like were do i go to get one your great ps i did it and its awsome but it took me about like three months to get a spring that was good
i made the gun and it sucked, the bb only shoots like five yards . . . . . . . . . . . idk maybe it's the spring?
Camster911 (author) 7 years ago
By The way, in all this pictures the gun is upside down to show you how to mkae it, the screw should be under it. You pull it back, twist to the side, and aim, and press with your finger sideways to fire. :)
how do you make the gun hold the BB in place when you cork the gun before shooting? Because I am making a bb gun out of a toy gun as it has the basic shape. There will be a lot work to do. In Singapore any form of bb guns is illegal and will be charged in court for owning a fire arm.
Agreed. In America, we can build our own guns. I couldn't imagine not having at least some sort of BB gun laying around the house. I have 2 custom ones (one's broken, the other half-finished), several hand-made rubber band guns (a dual-shot rifle, a simple pistol (instructable on it), and a bigger one designed to shoot high-power rubber bands.), and other assorted weapons, including a few airsoft guns, and some of my projects.
my word, its illegal to have a BB gun? that would make it illegal to have a firearm?!?!?! wow......pls come to america and we can shoot some stuff together.....
Thanks
.Jimb0.5 years ago
kenny1678 - you should be able to find all this stuff at bunnings
as for the spring go to colli hardware... i found crap loads of springs there. but going to toys are us and buyin a nerf nitefinder and then converting into a bb gun is heaps easier.... and saves time and money.
lolz thats what im doing
where do you get the spring?
Any airsoft site except air splat , they suck or your local hard wear store P.S Im 11
im 10
Fashim4 years ago
Hmm if your australian find one lol thats helpful well good luck to me
sharlston4 years ago
just finished making one of these
sk8dude114 years ago
i made one of those on my youtube here's the vid

http://www.youtube.com/watch?v=tmzj2YwpT9M
-JESUS-5 years ago
Haha! "Airgun Spring - Check your local airgun shop, or if your australian, find one." So true...
great idea! i would like to see a photograph of the finished product though
if i get some more money than ill make one THX BRO
oh, and if you make bb's from solder they will explode
oh, cool, how'd you do that???

check this site outlink
ohhh... cool. not my thing though... i don't like messing with molten lead, unless for soldering...
use solder instead of lead
solder has lead in it... anyways, i don't feel like wasting my time casting when i can just buy normal ones...
(removed by author or community request)
huh?
never mind
freerunnin15 years ago
ive got that sort of mechanism in 1 of my old dart guns so ime converting it into a bb gun
collard415 years ago
i have been designing a trigger mechanism, using a lever to release the spring, and it also has a safety catch.
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