Remember the 1925 SAAMI standard.
From "Proof Tests and Proof Marks, Part IV: Practices of Manufacturers in the United States", by LTC Calvin Goddard, May-June 1934 Army Ordnance Magazine
2-9/16 16g 10,100 psi "Service Working Limits"
If your Sterlingworth is a 1925 or newer gun, then it should deal with the "Classic" with aplomp. In addition, the SAAMI standards were themselves set to reflect "...maximum requirements reported by the leading companies.. they are intended to cover all variations" .
If the gun is in good condition, I would sweat neither the ammo nor lengthening the chambers. I know of no experimental data that suggests that chamber lengthening reduces recoil.
Regards
GKT
Texas Declaration of Independence 1836 -The Indictment against the dictatorship, Para.16:"It has demanded us to deliver up our arms, which are essential to our defence, the rightful property of freemen, and formidable only to tyrannical governments."
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