I've been wanting to build a fun gun project. So I've been looking for a modern cannon barrel to build off of. My ideal chamber would be 30mm because of the many different shell types. But I'm most likely going to shoot lead. But it's nice to know if needed I can fire modern shells.

So I've been looking for a barrel. But haven't had any luck finding anything under $1k. Even surplus. I've even talked to GE and they cannot sell and wouldn't even give me a price. Well I'm in no hurry sense time is all I have, and this is a fun project.

Thanks for your time.

Great idea; BUT, before you start, realize that a 20 or 30mm, or anything bigger than a .500 bore diameter, is a destructive device and you have to have a permit for it. Check with the ATF before you do anything, otherwise it is ten years and ten thousand dollars.
GE is NOT going to sell you a barrel.
Now, the legal way, without a permit, is to build a muzzle loader.
Now, you just have to first build a rifling machine, and do it yourself. Not that hard, I see you built a CNC router so you can certainly build a rifling machine. Use DOM tubing.

Oddly enough Tom, here in communist Canada you can own any sort of cannon your little heart desires. As long as the rounds are not explosive charged. I have monkeyed with the idea of building a variant of the breech loading 1890 Hotchkiss mountain cannon for years. Probably 37mm to keep it manageable and shoot 1-1/2 x 4 inch aluminum babbits. The receiver would be no problem and could easily be made with non-heat-treated 1018 as long as you build it massive enough. The problem is finding a cheap 37mm barrel.

I looked into building a mortar. They are quite prevalent and shoot bowling balls. The plain ones that vaguely resemble a Civil War mortar are no issue. Add a bipod with traverse, elevation and leveling capability and you have crossed the line into the forbidden zone.

I guess the govment don't mind ya shooting bowling balls, they jist donna want ya to aim them.

That is odd about Canada; I forgot to mention that shotguns and sporting rounds, are exempt from the over .500 thing.

A 4 bore in either muzzle loading or cartridge comes in about 25mm. Rifled barrels are available.

10ga is 19,65-19.7mm .. just saying

quote:

Originally posted by dpcd:
That is odd about Canada; I forgot to mention that shotguns and sporting rounds, are exempt from the over .500 thing.

I have never actually taken it through proper channels with the RCMP to see if there were any stumbling blocks to it Tom. But there seems to be nothing in the firearms act to the contrary. I just checked the RCMP verifires table and according to that, the 20mm Lahti is a non-restricted rifle so you can buy it as easily as a Winchester 94. Just a bit more expensive to shoot. The Hotchkiss 1934 cannon is also listed as non-restricted and that's chambered in 25x194R which is no slouch in a ground hog pasture either. I couldn't find any 37mms at all on the list. Which could simply mean that none were ever registered way back when in the days of the firearms registry. If the 20mm and 25mm are non-restricted I don't see where a 37mm would be any problem. Except for the added 500 pounds that you would have to add to make it strong enough and keep it from doing back flips when you fired it. My first stumbling block was actually just finding a used 37mm project barrel. I'm sure Apex or any of the other outfits in the USA that knock out barrels for the big stuff would make me one so long as I cleared it with the proper channels in Ottawa. But I have a sneaking suspicion that they might probably charge me a couple thousand dollars for it plus another couple thousand for the paperwork with the BATF, department of commerce, export permit and shipping. That's a bit more than I want to spend to throw some aluminum billets at cinder blocks.

2 Bore is bit over 33mm.

http://www.stolzergunsmithing....orejonesfinished.htm
And if you get really ambitious you can build a Double Rifle.

http://www.stolzergunsmithing....2boredoublerifle.htm

The OP is looking for a 30mm US, GAU 8 (GE, A-10) barrel; which, are not sporting cartridges. Classified quite differently than a 4 bore or ten gauge.
Mortars? sure I have built them; quite legal IF they do not fire fixed ammunition. IE, they have to be externally fired.

quote:

Originally posted by dpcd:

Mortars? sure I have built them; quite legal IF they do not fire fixed ammunition. IE, they have to be externally fired.

Kill two birds with one pound of black powder Tom. A mortar the shoots old Mauser barrels!

OK, I'll shut-da-fawk-up now. he he

Alright, when I posted this I had no idea of the positive reaction I would get. I am in the right place. I've been jaded by many people who don't understand us.
I also have to say I'm enjoying the comments. Thank you.
Also thanks for the reminder on hitting up the ATF. I didn't think about how it's considered a D.D.
That's just going to make the build that much more costly. Ugh, f**king over regulation. Shall not be infringed my fuzzy white ass.

Your title says 20mm+ but your post indicates 30mm...if you want a 20mm barrel Pac-Nor makes them.
http://pac-nor.com/barrels/
Scroll down to the bottom.

Price list:
http://pac-nor.com/pricelist/

Hope that helps.

quote:

Originally posted by CowboyCS:
Your title says 20mm+ but your post indicates 30mm...if you want a 20mm barrel Pac-Nor makes them.
http://pac-nor.com/barrels/
Scroll down to the bottom.

Price list:
http://pac-nor.com/pricelist/

Hope that helps.

Well that's where the + comes in. :-P

As a disabled veteran I don't have a ton of money to spend and what I don't have I have to stretch it. I'm guessing beggars can't be choosers.

What I'm looking to do is build, or most likely going to happen, is a mounted single shot plinker. I may go trailer mount, or even tripod. A friend of mine wants to put a turret ring on my pickup. I told him we'd hopefully would never need that in our search and rescue team. But then again when tracking fugitives the fear factor could be a benefit.
The year before I joined they moved on a guy hiding in the woods. Most are veterans or retired police... the state police credited the for his surrender. One look and help dropped his gear and surrendered to the first blue uniform he saw. "They're going to fucking kill me". Our orders were to track and hold for police. Engage only if fired upon.

Wish I had seen that. Helmet cam footage was taken into evidence.

That's a bit off topic.


Thank you for the lead on the barrel.

I'm still looking through the ATF website. Haven't found what I'm looking for.... I may have to call them. I hate talking on the phone.

Talking to them on the phone is a waste of time and it literally means nothing. If you want to stay out of jail then a letter from tech branch is the only way to go. They can always reverse a tech letter but at least when it comes to proving your intent in court the letter show you ask first and they said yes.

quote:

Originally posted by CowboyCS:
Talking to them on the phone is a waste of time and it literally means nothing. If you want to stay out of jail then a letter from tech branch is the only way to go. They can always reverse a tech letter but at least when it comes to proving your intent in court the letter show you ask first and they said yes.

Sounds Like solid advice. Thanks.


Anyone else have links to barrel manufacturer's or blueprints on barrel making machine? I've never reamed a barrel before. Working on it makes me a bit nervous. It's the small percentage I could screw it up.
If I'm going to be doing the barrel myself. Advice? Education or how to videos? Maybe YouTube?

You aren't trying very hard; it is FORM 1. You must file a ATF form one and get it approved before you do anything. First make sure your state allows DDs. some don't. The tax to file the form is $200.

If you are really going to make a high pressure, smokeless powder 30mm barrel you will need some specialized machinery, a lathe, and a rifling machine, which will cost a few grand to build. Search the net and you will find how to rifle a barrel. You have to use barrel steel, which is chrome moly, in the 4000 series. None of this will be cost effective for you to make one barrel.
I recommend you get a piece of steel 1 1/4 ID DOM and make a black powder muzzle loader, smooth bore cannon and save a lot of time, money and effort. It will still be very impressive when it goes off.

quote:

Originally posted by dpcd:
You aren't trying very hard; it is FORM 1. You must file a ATF form one and get it approved before you do anything. First make sure your state allows DDs. some don't. The tax to file the form is $200.

Been kinda busy, let alone first time on that website.

Probably hard to beat this:

http://www.gunbroker.com/item/647181295

NOS 20mm M103 Vulcan barrel for $1200, for anyone reading this after the link expires.

I also read years ago about a guy who made a 20mm muzzle loader. IIRC, he had been a Navy pilot in the 1950s and was flying at extremely low altitude, when he had to pull up for a hill, and got some wooden fence post in one of his gun barrels. He got to keep it, and years later had a bit of fun with it.

Gunbroker also has an 80% receiver for 20mm. It's listed at $4,000. Go muzzle loader. Both are wildly impractical. One can be built for less than the price of a new car.

Price goes up as bore goes up...or as they get harder to find.

http://www.gunbroker.com/item/657937472

25mm Bushmaster barrel for $4,600

HEY! 2 Gauge smoothbore barrel. Build a punt gun. This one is only $450.

http://www.gunbroker.com/item/658159089

Same seller for all this stuff. He also has 4 and 8 gauge barrels.

IMHO, one of those smoothbore barrels could be the start of a pretty cool project. If you build a single shot shotgun, you can get brass shells for it. Then get a mold made for rifled slugs.

The easiest and cheapest way to go bigger than a 50 BMG is with cannons and mortars. I am waiting on a copy of a 14th century swivel mount breech loading 3lb cannon (about 70mm) that should be able to run as much as 10 rounds per minute with practice and enough pre-loaded powder mugs. I have the same design in 1lb now and it takes about 5 seconds per shot but I only have 4 powder mugs for it. It's been enough to keep the pirates off the lake so far but bigger is better.

If you want to be creative, you could do a quad 50 mount and multiply the diameter by 4.

Haven't been in touch for some time, but Old West Scrouger, once out of Montague CA shot and collected all manner of cannons..Might be worth an internet search.

Dave's friend, Tom Phair (Phair's of Orinda CA) was also a cannon enthusiast. Good luck

CA! The shipping will be steep. But if I want a fun gun I guess.

Depending on more research I may end up just building a .50 BMG. Maybe make it a wildcat and get some extreme FPS out of it.


Build a trailer mounted gun built for extreme range. Make it a modified WW2 looking AT gun.

I know I know I'm more or less joking when I say this next part.

I have a stripped lower I have yet to build. In the build find a way to incorporate the ar Lowe onto the mounted gun and bam, legal?

OWS is in West Virginia; not california.. Bought out by Navy Arms, which moved out of New Jersey a few years ago. They don't have any more of the old cannon parts like they did in 1980. That stuff is long gone.
Just to avoid sticker shock, for example, a 37mm AT gun, starts at $25K, and they go up from there. Not hard to get a real modern cannon, if you have money.
You can build a 50 BMG.
You can put your AR lower on any kind of platform you want as long as it has a barrel length of 16 inches and an OAL of 26, unless it was categorized as a pistol to start with .

The Weapon Hunter on the Smithsonian Channel restored a 20mm Oerlikon AA gun with some parts he got from Sarco. There's other collectors who have parts, pull up the video should help.

quote:

Originally posted by dpcd:
OWS is in West Virginia; not california.. Bought out by Navy Arms, which moved out of New Jersey a few years ago. They don't have any more of the old cannon parts like they did in 1980. That stuff is long gone.
Just to avoid sticker shock, for example, a 37mm AT gun, starts at $25K, and they go up from there. Not hard to get a real modern cannon, if you have money.
You can build a 50 BMG.
You can put your AR lower on any kind of platform you want as long as it has a barrel length of 16 inches and an OAL of 26, unless it was categorized as a pistol to start with .

Well if I go trailer mount it's probably going to be long as I can get. :-p

I have done a bit of research already. My job in the army was to fix everything that went bang. That includes the tow artillery.

I have seen quite a few systems out there for sale. I came across a 155 once that needed a complete overhaul. I remember I commented that it was the same price as my house! $70k

I'm thinking I'll have to contact the ATF and see about acquiring another freedom back and pay their freedom tax.

Would you want me to post photos of the build?

I'm still searching for barrels.

The one gentleman linked to Pac-nor. Their 20mm barrels are around $400. That's a great deal. Got to make sure it's not for black powder first.

I was at the metal dealer today. They had a bit of 4140 and 4130 Crom-molly. They was too busy to inquire about prices. But they did have quite a few barrel sized drops but solid stock only. Unless I wanted to build.264 to .308. But I'm sure I can get them to order anything ;-)

Of course post pictures. I love Artillery although I was in Tanks for my career. I never could see the point in shooting at anything you couldn't see. I was on a mission once when some 155 HE rounds landed 100 yards from my tanks. The fragments were pinging off our turrets. That was a pre-planned fire mission and they put it in the wrong place. We just buttoned up and waited it out as the rounds were in the air. I called for an "Add 200", but it was too late. Anyway, no more war stories;
Go the the G503 forum. (G503 is the supply code for jeeps) They have a section for artillery; guys have, and build AT guns to tow behind their jeeps. 37mm and 57mm.
Go here
http://users.multipro.com/bren...iann/M3AT%2037MM.htm
That guy used to sell kits to build AT gun carriages. Lottos pictures and some drawings.
Th

I have 4bore barrel 1" bore, to sell --$350

PM me if interested.Be equal to 25mm. Ed

quote:

Originally posted by dpcd:
Of course post pictures. I love Artillery although I was in Tanks for my career. I never could see the point in shooting at anything you couldn't see. I was on a mission once when some 155 HE rounds landed 100 yards from my tanks. The fragments were pinging off our turrets. That was a pre-planned fire mission and they put it in the wrong place. We just buttoned up and waited it out as the rounds were in the air. I called for an "Add 200", but it was too late. Anyway, no more war stories;
Go the the G503 forum. (G503 is the supply code for jeeps) They have a section for artillery; guys have, and build AT guns to tow behind their jeeps. 37mm and 57mm.
Go here
http://users.multipro.com/bren...iann/M3AT%2037MM.htm
That guy used to sell kits to build AT gun carriages. Lottos pictures and some drawings.
Th

I emailed the guy. Seemed quite helpful. Well wanted to help. Gave me a lead on a barrel on eBay, although I have to search for it.

Fast response too.

Piecing together all the little bits of information and rumors to fine that gold in the pan.

I never jump into a project without digging into it first.

Man all the gold mining references. It's like I've been spending all my free time gold panning.

used to fix everything in the army that went bang. Up to and including tow artillery. Although I wasn't trained on but still worked on selfpropelled.<br>I've always had a interest in tow guns of all types. Match that with an interest in long range shooting. I learned machine tooling at a local community college after the army and acquired the tools to open a small job shop. Although I don't work professionally because I'm a disabled veteran. There is a steel dealer 16miles from me. So I can get my hands on just about anything. Even built my own CNC router, although incomplete - due to distractions.<br><br>That said I do want to build a historically accurate gun, but, I going to build a 100% custom  carriage. Designed for extreme range. I kinda want to prove that mechanical and analogue technology is not obsolete.<br><br>Any knowledge or advice is always welcome. I'm what in the army we call a D.I.C.K. dedicated individual to collective knowledge. :-P not the insult kind.

If your BIY (build it yourself) / DIY itch needs more itching, I ran across these videos on youtube:
https://www.youtube.com/watch?v=GQKOHioHJfA
https://www.youtube.com/watch?v=D43ZeYu9dnM

There are other video's on making/doing your own rifling also

quote:

Originally posted by dpcd:
You aren't trying very hard; it is FORM 1. You must file a ATF form one and get it approved before you do anything. First make sure your state allows DDs. some don't. The tax to file the form is $200.

I was looking for a form with destructive device in the title not fire arm. That's why I missed it....

I haven't ironed out the details yet. That's what all this boils down to, barrels. What can I get. I don't want to buy something to be denied.

Sense I have that stripped lower and to save the trouble and two Franklin's maybe I should just build a .50 off that. Ugh,I are sad now...

This guy had fun ;-)

http://www.buckstix.com/howitzer.htm

Just to be clear; you must have the Form 1 approved before you even start building anything.

quote:

Originally posted by The Dane:
This guy had fun ;-)

http://www.buckstix.com/howitzer.htm

I had to follow the link and see what it was all about. I must say, this is very odd for me, but there simply are no words ! ! ! ! !

quote:

Originally posted by The Dane:
This guy had fun ;-)

http://www.buckstix.com/howitzer.htm

I saw this a long long time ago. And it was even older then. :-p

quote:

Originally posted by dpcd:
Just to be clear; you must have the Form 1 approved before you even start building anything.

Even if I decide not to go over .50cal and build of that stripped lower? I can still build that trailer mounted gun just sub caliber then I wished.

I know I know not MG either.

.500 Bores and below are not DDs and need no license to build. Sporting rounds over .500 bore don't either.

quote:

Originally posted by dpcd:
.500 Bores and below are not DDs and need no license to build. Sporting rounds over .500 bore don't either.

So as long as I don't use military standard ammo I'm ok?