Dart gun barrel help

[tigerblues28]

I'm working a new gun, my first QEV with a hammer valve.

Anyways I was looking at a .40 cal smoothbore blow dart gun for a barrel. 36inches to be exact.

I figured with consistent ammo would give me consist accuracy.

Can anyone with experience give me some answers to..

What kind of accuracy can I expect?

Should I also add a scope? I was thinking so.

My QEV and hammer valve works well with about 50 psi and a tiny chamber so I think with a large chamber and about 400 psi I should get some nice semi auto/consistent shots.

Nick

[wyz2285]

I with these darts, use 12mm OD 10mm ID aluminium tube as barrel, at 400 psi with a hammer valve piloted QEV, you'll get great range, accuracy and damage. Hope the dart's "skirt" doesn't explode with such pressure though, it's very thin and designed for human lung pressure
this has a barrel that fires these darts I linked.

[jackssmirkingrevenge]

The human lungs generate about 3-4 psi tops, so what works in a blowgun won't necessarily work in a high pressure pneumatic with a fast valve. Ideally you should chose darts which have full bore support while travelling down the barrel.

Looking at these for example: http://www.extremeblowguns.com/darts50.htm

The "stingers" and "super stunners" should be most accurate.

[wyz2285]

The human lungs generate about 3-4 psi tops, so what works in a blowgun won't necessarily work in a high pressure pneumatic with a fast valve. Ideally you should chose darts which have full bore support while travelling down the barrel.

True about the fast valve and high pressure, don't go for 100% full bore support though. I did full bore with mine at first and the skirt wore out after 2 shots.
With a long barrel, even blowgun with shop compressor will punch these through 1mm steel plate.

[jackssmirkingrevenge]

I did full bore with mine at first and the skirt wore out after 2 shots.

Hah! If you can re-use the projectile after even one shot, then you clearly weren't shooting it fast enough

[wyz2285]

Hum... Jack the dart skirt falls when hitting the target, the core is hardened steel...

[tigerblues28]

I with these darts, use 12mm OD 10mm ID aluminium tube as barrel, at 400 psi with a hammer valve piloted QEV, you'll get great range, accuracy and damage. Hope the dart's "skirt" doesn't explode with such pressure though, it's very thin and designed for human lung pressure
this has a barrel that fires these darts I linked.

Yep. Those are the ones 8) I hope to make a mag to fit 5 or so of them. That's just an idea though.

Ill have a 1500 psi pressure gauge on my chamber with a threaded a schrader valve as fill. Ill use a co2 bike tire filler.

So I have a wide range of psi to use. My chamber is 3/8th in brass.

I think I'll buy a blow gun and use 1/2 inch copper a the outer barrel.

My birthday was two weeks ago so I have about 50 dollars for spending.

[wyz2285]

1/2 too large, 3/8 fit them perfectly.
A revolver style mag it's easier than a box mag, like this:

[dart guy]

the only thing is if you go with a revolver you will need a blow forward bolt or else it wont launch. i have thought of a cartridge design in a box mag because more or less that is how my darts look, only bigger.http://www.spudfiles.com/pneumatic-cann ... 25355.html though it is only part way done.

[tigerblues28]

I'm working on the mag fed idea. Bolt action for the win!

I have some 3in pvc and a square form kind of mold to shape it into a rectangle to fit my darts. Then ill mold an epoxy port onto my 3/4" pvc pipe to except the mag. Hopefully tight fitting.

My hammer is an inline type of bolt action with a sliding piston. Ill further explan once it's more complete.

I'm open to hammer ideas. A blow back bolt from the pilot air. Who knows.

A cartridge is out of the question for now. I don't have the cash. I don't want to collect the cartridges after I shoot em' either.
And a ejector would be a pain in the rear.

Nick

[tigerblues28]

So, last Friday I was able to order a handful I parts like a small chamber, some co2, a threaded schrader, ad more importantly, my barrel an a few darts .


I picked up the 36" .40 cal blow gun with a 50 pack of spike darts. I was worried about the barrel arriving and being straight and not all bent up. So that's good. The spike darts aren't very high quality. The little plastic skirts split when I insert the harden steel spike into it.

They still shoot alright. Within 20 minutes I was getting 4 inch groupings at 20 paces. At 5 paces I was getting 1 inch groupings or so. Although this was breathe power and a lot of human error I think it will perform extremely well with a QEV behind it.

Now to experiment with some new darts. I need some heavy duty cones for them?

Could I cast them from epoxy? Should I ask a 3d printer guybto print me off a couple hundred?

Yeah, paper darts, yada yada yada.


Nick

[wyz2285]

The spike darts aren't very high quality. The little plastic skirts split when I insert the harden steel spike into it.

Don't know where you bought it, the ones I linked are pretty decent. The metal core should fit in a way that can be easily removed because the core is supposed to keep penetrating while the skirt fall off once you hit the target. If it split when you insert the core you've rather done it wrong or as you say, low quality.
I'd suggest buying better darts, it's probably the cheapest and easiest way.

[tigerblues28]

I think you're right.

I pushed the spike in too far. It's fine though. Most of them aren't cracked so. Whatever.

Ill use the cracked ones for playing around with. I bought the blow gun and the darts straight from the manufacturer I believe. The company's name is predator. They're from here in the US.


Nick

[wyz2285]

I use the same darts, their claimed to be "hardened" steel core isn't hard at all. shooting at a coin the core will happily bend A heat treated nail wouldn't have this problem. Heat treat the core or find similar size nails if you're thinking about shooting at something tough.

[tigerblues28]

Yeah I figured that out too. The long skinny darts that came with the blow gun get stuck in a penny, but no penetration yet.