APG-2 (Air Propelled Grenade, version 2)

[Secret Squirrel]

For the entirety of my short spudding career, my main project has been developing a shoulder fired launcher for airsoft use. My first cannon ever, the APG-1, was a 1.5" barrel, mostly dwv coaxial, that I never really felt was worth posting. It was loud, inefficient, and most likely dangerous to be shot with.

So with the APG-2 I've sort of taken a step backwards. The main valve is a 3/4" sprinkler valve (the APG-1's pilot valve...) with 2" by 18" barrel and chamber. Sure performance isn't great with a valve so much smaller than the barrel, but tests from a few minutes ago indicate that it is more than sufficient for it's intended purpose, so I'm happy with it.



Yes that is DWV you see, but all of it is purely cosmetic. Any parts containing compressed air are NSF-pw. The bell reducers just hide the sprinkler and quick disconnect.

Updates forthcoming with the addition of paint, grips, and other accessories.

-UPDATE-

I actually painted it a few weeks ago, just never got around to taking pics. Anyway, here's the APG-2 with Olive Drab and Flat Black paint.

The whole launcher


The valve and shroud


The fill valve (female QD)


And the view down the sights (at the floor)


Well I might eventually add a more comfortable pistol grip than the blowgun, but that's sort of doubtful, as the APG-3 is already in the planning stages.

-UPDATE AGAIN-
Ok, everyone;s comments inspired me to finally finish this thing. I added a sling made from a couple of belts, a pistol grip made from a chunk of blue foam covered in bondo, and stenciled "APG-2" on both sides of the chamber.

The finished launcher


Closeup of the chamber stencil

[Lockednloaded]

That looks amazing, it clean, ergonomic, and functional. All you need is a nice paint job, maybe another bell reducer on the barrel, and a pistol grip to make it look perfect

[clemsonguy1125]

That looks awesome, its sleek and effective. Ive got an old sprinkler valve laying around and you just gave me a few ideas.

[Gun Freak]

Really nice... I like the way you covered up the valve.

[mark.f]

Very nice. I always like to see people dress up their cannons with DWV because eventually somebody comes along and throws a fit.

[Gaderelguitarist]

That looks fantastic. I'll bet it packs a punch on the field. Only question is why did you mount the sight on the top? I would hate to try to look down the sight and fire this from my shoulder at the same time.

Plans for paint?

[Secret Squirrel]

Where else would I mount the sight?

With the sight where it is now I can see through it just fine with the chamber over my shoulder.

Paint is probably going to be olive drab on the pipe, and flat black on the fittings and grips. And as with real shoulder fired launchers it will need a set of obvious instruction printed on the side. "1. Aim at enemy..."

[jackssmirkingrevenge]

That looks fantastic. I'll bet it packs a punch on the field. Only question is why did you mount the sight on the top? I would hate to try to look down the sight and fire this from my shoulder at the same time.

Dimensions are similar to the LAW, it makes sense to have the sight on top.



Good job, in spite of the "inadequate" valve I'm sure performance is more than suitable for the purpose.

One thing I would probably have changed is the C:B ratio, smaller changer and longer barrel.

[Secret Squirrel]

One thing I would probably have changed is the C:B ratio, smaller changer and longer barrel.

I put the design through GGDT before building it. With the flow restriction of the valve the 1:1 C:B ratio turns out to be a near optimum ratio for the around 70psi pressures I'll usually run it at.

[jackssmirkingrevenge]

I put the design through GGDT before building it. With the flow restriction of the valve the 1:1 C:B ratio turns out to be a near optimum ratio for the around 70psi pressures I'll usually run it at.

Fair enough, probably as you're using such a low density projectile.

[Secret Squirrel]

Updated with pics of the now painted launcher.

[jackssmirkingrevenge]

Very nice, just needs some stencilling

[Gaderelguitarist]

Have you thought of taking any steps to covering the blowgun? You shrouded the sprinkler valve very successfully. Now that blowgun seems like a sore thumb.

[jackssmirkingrevenge]

Have you thought of taking any steps to covering the blowgun?

Yes... with his trigger hand

[LeMaudit]

Really impressive work! So clean, love it!
A bit of FIMO or thermoplastic on the handle and trigger would even more improve the look.

Or you could cover it with some shaped pieces of wood, and use some shrinking tubing to make an even and smooth plastic like surface to cover it.

Any chance for a shooting video?