Brass for Blunderbuss Barrel

[tiriaq]

I've been wanting to make a blunderbuss for some time. Have a suitable carbine sized lock, buttplate and some other bits.
A blunderbuss should have a brass barrel. But what sort of brass would be suitable - ie - strong enough - for use as a barrel? Originals were likely cast, but I'm not going there.

 

[Road King]

Admiralty brass or Naval Brass

 

[tiriaq]

Hmmm.
I worked with a modern brass/bronze whaling gun that used 8ga blanks to launch a 1lb bomb. It was made in a marine machineshop.
Bet that is what was used.

 

[Road King]

If you are going to turn it down on a lathe may want to consider yellow brass or any brass with a low zinc %. To much zinc and the brass becomes brittle.

 

[Road King]

http://www.natscience.com/Uwe/Forum.aspx/physics/26790/Magnitude-of-thermal-expansion-force-in-metals

Check this site, in one of the posts it mentions Admiralty brass for cannon barrels.

 

[tiriaq]

Thanks for this!

 

[mooncoon]

I would lean towards silicone bronze purchased as a very thick wall tubing and put a threaded breach plug in it. I would also think you might find some info on work hardening properties of brass alloys in Machinery's Handbook. On another forum, one poster claimed that brass becomes brittle as opposed to bronze

cheers mooncoon

 

[cantom]

Thanks for this!

http://americanlongrifles.org/forum/index.php?topic=1063.0

U.S. Government bronze specification G is a gunmetal composed of 88% copper, 10% tin, and 2% zinc.

Personally, I lean towards the steel liner idea. No harm in making sure the thing isn't going to explode, right beside your head.

Material:Copper Alloy Number 464 -- Wrought Naval Brass, Non-Leaded Naval Bronze, CDA 464
Naval Brass or C46400 is a high strength, corrosion resistant alloy containing nominally 60% copper, .75% tin and 39.25% zinc. It is widely used in marine construction where a strong, corrosive resistant and hard material is required. It is available at a comparatively low cost.



ht tp://www.stonewallcreekoutfitters.com/barrels-2/rayle-rifle-barrels/

 

[tiriaq]

The parallel portion of the bore could be sleeved with steel from the breech foreward to the start of the flare. Once the flare is reached, pressure is going to drop really quickly.