Flak Gun Help

[ShowNoMercy]

So as of now I have the money and a vague idea of what I want to build, so I just need a bit of advice for my cannon. I want to make it with a 2 inch barrel by maybe 20 feet and I want it to be semi. So far I am perplexed by how to accomplish this. The ROF could be as slow as sin but I want to make it so I can shoot and reload without doing much. I was trying a blow back design but I fear it wont work. My other idea is a bolt that has a spring attached to the back of it to pull it back and the back is pressurized with the main chamber. So when the chamber is pressurized the bolt closes, with a round in the action and then after firing the bolt opens and grabs another round. Thats my idea that I like as of now. My primary ammo is gonna be caulk tubes and I will make it gravity fed. Any thoughts? Btw I want to style it after a WWII flak gun. If I get the semi to work I will attempt to build a carriage for it.

[judgment_arms]

Which WWII flak gun are you talking, the FLAK88, the Bofors 40mm auto-cannon, the 37mm antiaircraft gun, the 3 inch antiaircraft gun, or what?

Your idea sounds sound enough, not what I’d do but if you can make it work, good for you.

[ShowNoMercy]

I really didn't have a set idea of what gun I would style it after but in reality I just want it to work.

[judgment_arms]

I’m trying to find the Holy Grail to, so you’re pretty much on your own with the workings.
But as for the aesthetics I can lend a hand there.

[ShowNoMercy]

Well I may go for a floating barrel attack on it. The prob with that is that I either need two small air rams or a larger one with a 9 inch extend. So I am still on the drawing boards as of now.

[judgment_arms]

I know the feeling…

[Hotwired]

Sucks trying to find a simple and efficient loading mech that doesn't require detaching the whole dam barrel every time.

I mean it is possible to have the valve barrel port at 90* to the actual barrel so you can use a bolt from behind the valve position but it needs a lot of travel.

Hmm.

Funny how describing your own problem to someone else can make a solution become apparent.

*reaches for sketchpad*

[judgment_arms]

Funny how describing your own problem to someone else can make a solution become apparent.

Indeed…


Hay hay hay!
Your shooting caulk tubes right… google “recoil operation”.

[ShowNoMercy]

Yea but then the valve and opening in the port need to align after every shot. Which I have thought about but it is gonna take a lot of material cooperation and patience.

[judgment_arms]

How bout this:
Whole gun recoils in mount.
As barrel recoils it rotates and unlocks from the rest of the gun.
The rest of the gun locks back and the barrel returns to battery
New round falls in to place
Squeezing trigger releases gun to slide forward, lock with barrel and fire.
Reapeat.

[ShowNoMercy]

Bit complicated for me there, I am trying for a really simple approach to this. My plan now is to have a floating barrel and have a air ram cycle it froward and back to load. My new problem is how to load. Should I make a gravity fed mag or spring loaded one?

[judgment_arms]

Gravity.

But your design sound complex to me…

[ShowNoMercy]

Nah, its simple basically its a bolt action but instead of you operating it a ram cycles it. Simple in idea but hard to apply. And with a gravity feed how do I keep the caulk tubes from going straight through the bolt?

[judgment_arms]

Use 1.5in. for the bolt have it ride inside your barrel, cut an opening in the top of the barrel towards the breach for the rounds to drop in.
That way the round just falls into the barrel and the bolt pushes it past the loading port.
If I don’t make sense sorry, I got a head ache.

[ShowNoMercy]

Genius! Sweet I shall return to the boards and hopefully tommarow get some of the pipe. You gonna sell those rifled barrels Judge?