More good info from Dr Drew.
Actual tensile strength testing of Twist and Crolle Damascus barrels show an average of 54,000 psi, or about half of the published industrial standard for AISI 4140 Chrome Moly gun barrel steel.
For that reason I favor as MWT for pattern welded barrels:
End of chamber - .105"
Forcing cone - .100"
9" from breech - .040"
9" from muzzle - .025"
Factory original 20 and 16 gauge small frame guns with Damascus barrels however may have a wall thickness of .090” at the end of the chamber, and .020” in the distal third of the barrel, making it critical to use loads that match the ballistics of those originally intended for use in the gun.
Last edited by ithaca1; 04/19/15 02:53 PM.
