2-piper:
Yeah, but we get too technical with the values of pi, the mass of lead and the string of sig-figs . Without a doubt they were doing it long-hand and I'm sure rounded, which is difficult to determine to where or what they rounded. Therefore, somewhere there was a published chart that the proofhouses were using. Your mention of thin jackets and say the plug gauge value 181 for 7.7X57R or 0.303" British leads me to believe that below .30 cal they may have gone to 1/2 of the 0.01" interval which would be .005". That's about the only way the "181" stamp as well as the "248" and "468" for something akin to the 5.6 Vom Hofe; a stamp I haven't seen yet. As the calibres become smaller, the gauge heads toward infinity, quickly. For anyone interested who has been following this exercise in mathematics, somewhere around 0.261" the plug gauge equals 261.
Steven:
So when & where did the "181" for 0.303" originate, as well as the "184,11" for a 0.295"? All the "181" stamps I've seen were under the "Crown" over "U" as described on the drilling.
Kind Regards,
Raimey
rse
Last edited by ellenbr; 12/17/08 05:49 PM.
