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Posted: Fri Oct 21, 2011 5:25 pm
by POLAND_SPUD
I think you should take into consideration what other members have said
This project might be a bit too ambitious

Ask the guy what range etc. they really want and whether you really need that shell ejecting

Seriously there is no practical reason to build a cartridge hybrid (sorry JSR :-D)

Posted: Fri Oct 21, 2011 7:31 pm
by Zeus
PS, you make a good point bar the cartridges. You should be able to exceed 1000RPM with cartridges, which a tradional hybrid couldn't hope to match. I won't even mention pneubmatics.

Posted: Fri Oct 21, 2011 8:15 pm
by warhead052
Alright, the captain said 100-200 feet is okay, but would like some longer range for taking out airsoft tanks. Is this possible?

Posted: Fri Oct 21, 2011 8:16 pm
by Gun Freak
100 yards sounds doable to me... Pneumatic of course... Lol

Posted: Fri Oct 21, 2011 8:18 pm
by Zeus
SB and others have got 300 yards and up with a combustion, a decent projectile, good barrel and a hybrid would reach that far easily.

Posted: Fri Oct 21, 2011 8:34 pm
by evanmcorleytv
warhead052 wrote:Alright, the captain said 100-200 feet is okay, but would like some longer range for taking out airsoft tanks. Is this possible?
You should get WAY longer than that with a large cannon.. again, my weak bazooka shot about 200 yards (600 feet) and gave 5-8 inch DARK PURPLE bruises with 150 PSI.. So.. Yeah.. And with pneumatics, you'll be able to easily adjust the range, and power of your cannon, and if he has an air compressor, then he would have almost unlimited fills!! Not to mention that the loading system I designed could work with combustion, pneumatic, and/or hybrid cannons!! haha

Posted: Fri Oct 21, 2011 9:06 pm
by POLAND_SPUD
PS, you make a good point bar the cartridges. You should be able to exceed 1000RPM with cartridges, which a tradional hybrid couldn't hope to match.
RPM ?
naahh but seriosuly what's the point ?

Most modern howitzers use charges + seperate shells - not cartridges

So a cartridge feed howitzer will not look very realistic

Build a pneumatic
but would like some longer range for taking out airsoft tanks. Is this possible?
hmm that is a very vague statement you know :wink:

the problem here is not the power of the gun but external ballistics... your ammo has to be safe (which comes down to - it can't hurt anyone at any range) but safe ammo has to be light

light ammo = slows down rapidly = short range

I've never seen a nerf pocket rocket let alone shot it but it seems that the max range for them is under 60 feet


All in all it seems that the whole project isn't really that practical... can't you just build him something like this ?
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Posted: Fri Oct 21, 2011 9:12 pm
by Gun Freak
Nerf pocket rockets will go for a hell of a lot longer than 60 feet. Hell, I can throw one much further than that.

Posted: Fri Oct 21, 2011 9:15 pm
by warhead052
Well, I guess pneumatic it is then... So much for the bang...

Posted: Fri Oct 21, 2011 9:21 pm
by dewey-1
I've never seen a nerf pocket rocket let alone shot it but it seems that the max range for them is under 60 feet.


Trust me, with an 1-1/2 porting pneumatic valve with a 3 foot barrel it will easily go 300 to 350 feet.

Posted: Fri Oct 21, 2011 9:25 pm
by Gun Freak
I have one that is dying to be shot, once I get the right barrel. :D

Posted: Fri Oct 21, 2011 9:28 pm
by POLAND_SPUD
go 300 to 350 feet.
if that's the case then sorry though I stressed that I've never shot one

well anyway, max range is one thing effective range is something different... any idea how accurate are these things ?

Posted: Fri Oct 21, 2011 9:41 pm
by Fnord
If you can get a compressor on site then a pneumatic will work just fine, though won't really have the authentic feel of course.

If you'd still rather have a bang/muzzle flash, I still can't see any flaws with using the oxy-mapp cartridges.

A prototype launcher for testing would be a good place to start. Consider the materials;
2"x 12 galv pipe(chamber/breech)
2" cap
2" x 4' abs pipe (barrel)
2" female thread adapter
disposable oxy/fuel cyliders ($20)

igniter and meter you probably have already

Again, this is just a test example; you'll want to replace the plastic barrel later for safety's sake.
I honestly don't think a cartridge design could be much simpler, but if it doesn't work for any reason, you've only lost ~$50

Posted: Fri Oct 21, 2011 11:13 pm
by evanmcorleytv
Also, If you do end up going with pneumatic, I would go with this design:
And instead of using a ball valve, or a 2 inch sprinkler valve, I would use a piston valve!!

Link:

http://www.armoredfistpaintball.com/bergles_cannon.htm

It allow you to load ammo from the rear end, and have high rates of fire, along with a compact size, and PLENTY of power!!

Posted: Sat Oct 22, 2011 2:52 am
by jackssmirkingrevenge
POLAND_SPUD wrote:Seriously there is no practical reason to build a cartridge hybrid (sorry JSR :-D)
I won't take hybrid advice from someone who never presented one ;)