I HAVE DONE ALOT OF RESEARCH ON THIS GUN,BUT THERE ARE SOME CHARACTERISTICS THIS GUN HAS,THAT ARE LACKING ON ANY OTHER 1901 MODELS WE'VE FOUND. PLEASE HELP IF YOU CAN. TOP OF BARREL (6" BARREL) IS IMPRINTED "COLT.DA.38. COLTS P.T.F.A.MFG.CO HARTFORD CT.USA" PATENTED AUG 5 1884,NOV 6 88,MAR 5 95. BOTTOM OF BARREL STAMPED "R.A.C" and LETTER "P"(UPSIDE DOWN) STAMPED " US ARMY MODEL 1901 "ON BOTTOM STRAP,"No. 1052" BELOW LANYARD HOLE. "R.A.C" STAMPED ON THE LEFT SIDE OF LEFT SIDE OF FRAME JUST ABOVE THE GRIP. HAND CHECKERED HAMMER AND CYLINDER RELEASE.CYLINDER RELEASE STAMPED "1052" WITH A "K" ABOVE NO.CRANE IS STAMPED "1052" ON MAIN FRAME WITH NO."1" ABOVE.AND NO." 7 " BELOW.CRANE IS ALSO STAMPED ON CRANE SWING OUT CYLINDER "1052" WITH LETTER "K" ABOVE. THE No."74" IS STAMPED ON MAIN FRAME HEAL STRAP LEFT SIDE,UNDER GRIP(WHEN REMOVED) SIDEPLATE,RIGHT SIDE,INSIDE,STAMPED "R.A.C", CYLINDER TURNS COUNTER CLOCK WISE,HAVING 1 " FLUTES WITH ROTATION AND EXTRA LOCKING NOTCHES. CYLINDER(REAR)STAMPED "R.A.C."NOS."71 27 K" ON FACE AND THE NO."526 40."UNDER RACHET ON CYLINDER.EJECTOR ROD STAMPED NO. "7950" WITH A SMALL NO."7" ABOVE AND TO THE LEFT SIDE OF THE 5 CONTAINED AMONG THE 7950. BLUING ORIGINAl IS 75% ORIGINAL OVERALL,WITH SOME HOLSTER WEAR ON BARREL,CYLINDER,CRANE FORWARD OF TRIGGER HOUSING,AND CYLINDER RELEASE. IN A NUTSHELL WE HAVE FOUND NO OTHER 38 DA WITH ALL THE MARKINGS ON AS MANY PARTS WITH INSPECTORS INITIALS SUPERVISING,STAMPING THE CONVERSION. THANK YOU FOR ANY LEADS