For Shootable Barrels
We use methods of production which duplicate the late 18th and 19th century practice for cast field ordnance which is to drill the bore into a SOLID CASTING. This technique provides the soundest product since there is no core to cause gas pockets in the heart of the casting. That’s why WE DO NOT CAST AROUND SLEEVES like some of our competitors, and try to pass off some SURE LOCK method, nor do we cast around cores of any type plus all of our bronze barrels are cast VERTICALLY. Whatever minor impurities are present in the liquid metal when we cast a barrel solid, will normally freeze to the center of the casting, or in bronze, rise to the top into a dead head where they are removed in the drilling process. This was the technique to fabricate all cast iron and bronze field guns of the major powers in the late 18th and 19th Century. This method also will provide a much straighter bore than can normally be made by casting around a core of any type.
The overall method of pouring solid, drilling, and sleeving is more expensive than the core-process methods of gun making, owing to specialized deep-hole drilling equipment needed, and implementation time. But at the same time, special benefits of the method include direct “reading” of metal during the drilling process, step-by-step checks and controls as construction progresses, and absence of all problems relating to heat distortion. Additionally, since no expanding air or foreign material is trapped in solid-poured castings, the tendency toward soundness of castings is enhanced. Outer blemished, as may from time to time appear, are usually only superficial and can be readily examined in whatever case. The benefits of the latter toward further finishing, including lathe turning are obvious. In addition to lathe turning, all of our reproduction barrels are sleeved with D.O.M. extruded seamless steel tubing of a minimum ANSI standard and a minimum 1/2 “wall thickness”. The sleeve is closed at the breach end with a steel plug, THREADED into the liner and welded. The breach plug has a radius of 25% of the bore radius and is 1″ thick at the thinnest point. Pictures of the liner and breach plug are available upon request to meet all N-SSA requirements for firing of piece.
Our guns come equipped with a threaded vent piece made of copper, so that in the extreme event that a round cannot be fired and must be removed from the gun by other means, the vent piece might be removed, making the flushing of the powder charge–with water–much easier, and more positive. (Only after the powder has been flushed should any attempt be made to pull the projectile from the muzzle by any mechanical means) Other advantages of having a threaded vent piece is if a cannon is scheduled for heavy use, such as hourly firing at a historic site for several months a year, the vent piece can be easily replaced as it becomes enlarged from continual use.