Cannon breech designs??

MAD DOG · May 8, 2000, 11:47 PM

I am considering the building of a 40mm cannon, and need a breech design that is relatively simple to construct.

Failing a suitable breech design, I will make it a muzzle loader.
Bear in mind that I do not want to do a full "modern cartridge" type of design, due to the regs.
Just a simple bag and ball fed breech loader will do nicely.

I understand that the Whitworth breech design is good, but I am unfamiliar with it.
Anyone have a design, or know where one can be had?
Comments?
Suggestions?

Nestor Rivera · May 10, 2000, 01:54 PM

If you don't need to have a swinging breach a simple interrupted screw arrangement with the bore being smaller than the breach
so the "plug" could have a gas seal. Get a copy of Ian Hoggs book on the history of artillery it has very good illustrations

STLRN · May 10, 2000, 05:00 PM

There are "standard" types of artillery breaches in use today. The first being the interrupted screw breach. These types of breaches are normally used for caseless or bag powder charges. The heart of this breach is the Debange obturator. Which uses two or more split rings and heavy duty rubber pads to create a seal. The second type of breach is the sliding block breach (either horizontal or vertical). This type of breach is normally used for fixed or semi-fixed rounds. The breach relies on a brass cartridge to actually seal the breach. The block slides across and locks into a heavy portion of the breach to ensure the brass is seated and doesn't "back out"

Juan Hunt Greer · May 10, 2000, 10:32 PM

You might try simply a scaled- up version of the percussion Sharps breechloader with a reduced-scale lever set. crankshaft

beemerb · May 10, 2000, 10:48 PM

I may be way off base and I hope I am.IF memory serves me correctly a breech loading cannon is a destructive device.It doesn't make any diff if ammo is fixed or not.I would check before I start to build.

------------------
beemerb
We have a criminal jury system which is superior to any in the world;
and its efficiency is only marred by the difficulty of finding twelve men
every day who don't know anything and can't read.
-Mark Twain

May 8, 2000, 11:47 PM	#1
MAD DOG Senior Member Join Date: October 13, 1998 Location: Arizona. Posts: 853	I am considering the building of a 40mm cannon, and need a breech design that is relatively simple to construct. Failing a suitable breech design, I will make it a muzzle loader. Bear in mind that I do not want to do a full "modern cartridge" type of design, due to the regs. Just a simple bag and ball fed breech loader will do nicely. I understand that the Whitworth breech design is good, but I am unfamiliar with it. Anyone have a design, or know where one can be had? Comments? Suggestions?

May 10, 2000, 01:54 PM	#2
Nestor Rivera Senior Member Join Date: October 20, 1998 Location: San Antonio, Texas, USA Posts: 446	If you don't need to have a swinging breach a simple interrupted screw arrangement with the bore being smaller than the breach so the "plug" could have a gas seal. Get a copy of Ian Hoggs book on the history of artillery it has very good illustrations

May 10, 2000, 05:00 PM	#3
STLRN Senior Member Join Date: October 28, 1999 Location: USA Posts: 1,163	There are "standard" types of artillery breaches in use today. The first being the interrupted screw breach. These types of breaches are normally used for caseless or bag powder charges. The heart of this breach is the Debange obturator. Which uses two or more split rings and heavy duty rubber pads to create a seal. The second type of breach is the sliding block breach (either horizontal or vertical). This type of breach is normally used for fixed or semi-fixed rounds. The breach relies on a brass cartridge to actually seal the breach. The block slides across and locks into a heavy portion of the breach to ensure the brass is seated and doesn't "back out"

May 10, 2000, 10:32 PM	#4
Juan Hunt Greer Senior Member Join Date: April 7, 2000 Posts: 449	You might try simply a scaled- up version of the percussion Sharps breechloader with a reduced-scale lever set. crankshaft

May 10, 2000, 10:48 PM	#5
beemerb Junior member Join Date: October 2, 1999 Location: AZ Posts: 1,759	I may be way off base and I hope I am.IF memory serves me correctly a breech loading cannon is a destructive device.It doesn't make any diff if ammo is fixed or not.I would check before I start to build. ------------------ beemerb We have a criminal jury system which is superior to any in the world; and its efficiency is only marred by the difficulty of finding twelve men every day who don't know anything and can't read. -Mark Twain