preloaded pneumatic cartridge

[jackssmirkingrevenge]

Could you make a 'magnum' cartridge, so that your ammo actually goes into the cartridge barrel? The end result would be like a coaxial gun with one barrel and exchangeable chambers. I guess that wouldn't make too much sense, though: may as well have a barrel for each chamber.

That would be ideal in terms of power, but personally there are two disadvantages, first of all since I don't have the benefit of a lathe, getting the cart to line up 100% with the breech would be very difficult. Secondly, the cartridge would be too bulky, for example for a 0.75" (19.05mm) barrel I'd like to have a cartridge that's dimensionally close to a 20mm cannon round, but as a co-axial it would be more like the size of a 40mm round.

[zomgwtfbbq]

Jack, when will you post more new photos?

[jackssmirkingrevenge]

when I actually shift my posterior and get to work - still trying to work out the best caliber and configuration, I'm torn between self contained cartridges or a re-visit of the cartridge fed concept, decisions decisions - and in the mean time going through Medal of Honor - Pacific Assault all in the name of "research"

[zomgwtfbbq]

Ha ha ha. All the best to you man. I will be heading down to the arts and craft shop tomorrow to look for some of my parts. Ha ha this is probably the only form of shopping I do.

[jackssmirkingrevenge]

Ha ha this is probably the only form of shopping I do.

Enjoy it while you can, my g/f decided my wardrobe was still that of a teenager (hey, I was comfortable) and in the past week I've spent almost $600 on shirts, pants and shoes

[jackssmirkingrevenge]

Finally made some progress, started making cartridge version 2.0

[wannabie]

I get it i was staring at that last picture for about 5 minutes untill i realised how it worked i need to sleep...

that piston looks really tight what type of epoxy do you use?

[jackssmirkingrevenge]

that piston looks really tight what type of epoxy do you use?

Of course it's tight, it's exactly the same diameter as the tube it will be housed in, because it was after all cast in it

Re: the epoxy type, see page 4 of this thread.

[joannaardway]

Very nice. Kudos for the excellent work.

I'm seriously tempted to try this myself now - sod the legality.

[jackssmirkingrevenge]

Very nice. Kudos for the excellent work.

Cheers

Well, the cart is basically ready. The epoxy's still curing, I know I shouldn't have but I did a very quick test at low pressure and woo! it worked (It's always a bit hit-and-miss when you're dealing with epoxy, you know that if it doesnt work then you're screwed and have to start over) - next step is to duct tape it to a barrel and evaluate the performance (and make a few vidoes, as it is i think it's the most compact 3/4" launcher ever ), if I consider it to be worthwhile - my current standard is making a 3/4" hole through 1/4" ply - then I'll move on to building that anti-material rifle I always wanted

Anyways, on to the pictures:

[Skywalker]

Woot! Looks slick! I can't wait to see how the test fires go. How many will you make if it works? A dozen or so?

Are you going to just let the ejected carts fall to the ground? I guess that will work, b/c they should be easier to find than those little brass thingys you had on your earlier cart system. And I suppose it defeats the purpose of having carts if they don't eject, right?

[jackssmirkingrevenge]

The whole point of this project is to see the carts fly out, of course I'm going to let them eject assuming they have enough power to eject themselves of course, it's a pretty heavy thing and that remains to be seen. I'm thinking it will probably be like my other system in that it will need a bolt stop to chamber another cart. Ah well, we'll see. I guess I'll make around 5 in all. The Lahti L39 which should form the basis for my launcher had a 10 round mag, but then again, I don't have to face soviet tanks either

[frankrede]

The whole point of this project is to see the carts fly out, of course I'm going to let them eject assuming they have enough power to eject themselves of course, it's a pretty heavy thing and that remains to be seen. I'm thinking it will probably be like my other system in that it will need a bolt stop to chamber another cart. Ah well, we'll see. I guess I'll make around 5 in all. The Lahti L39 which should form the basis for my launcher had a 10 round mag, but then again, I don't have to face soviet tanks either

I don't have to face soviet tanks *yet*

[jackssmirkingrevenge]

I don't have to face soviet tanks *yet*

Even with its 50,000 ft/lbs, the Lahti was relatively useless against WW2 tanks, I doubt a PVC replica will be of much use against what the modern Russian armament industry has to offer.

[Hawkeye]

I think it would work better if it was shorter with a long piston to eliminate all that dead volume in the slim inner tube. Wasn't that your original plan?
3/4 inch copper and various fittings makes a perfect marble shell.