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Re: original design drawings

Posted by John on Thursday, 2 December 2010, at 1:00 p.m., in response to Re: original design drawings, posted by Al Frasca on Thursday, 2 December 2010, at 10:44 a.m.

Arms manufacture was an evolutionary business, heavily linked to precedents, and "we always did it that way" and bureaucratic inertia.

Recall that as late as the Civil War, federal arms contractors were NEVER provided any drawings, only sample or "Model" arms. Hall's breechloaders were the first U.S. martial arms to be 100% interchangeable, and the Model 1842 muskets were the first to be interchangeable between the two National Armories and the contractors.

By WW1 the shift from gauges to drawings seems to have been made. But, even then there were extensive problems getting M1911 pistols into production at Springfield and Remington-UMC due to lack of suitable drawings with noted tolerances. Similarly, Model 1917 rifle production took several months to begin due to different dimensions and tolerances among Remington, Winchester, and Eddystone. The Brits treated their Pattern 1914 rifles (direct predecessor of the M1917) as three distinct models based on manufacturer. Winchester took a gamble and made approximately 10,000 M1917s "on speculation" before final drawings were approved, resulting in a decree that they not be sent overseas as they were not 100% interchangeable with the finally approved design.

Brophy's "Springfield Armory: Arsenal of Freedom" is filled with laments in the Annual Reports about problems with drawings being behind the workload, especially circa 1916-1945.

Model 1903 rifle parts were thoroughly covered by drawings, and in 1916 Colvin and Viall (experts from "The American Machinist" magazine) published a book with all the drawings and also showing the jigs, fixtures and gauges involved. This both documented the processes used by Springfield, and was intended to prepare American manufacturers for possible production of rifles if/when WW1 involved America. It is not clear if Colvin & Viall merely copied SA drawings, or in fact prepared the drawings themselves.

I am not sure if Krags were built to gauge or to drawings, but do not recall ever seeing any dimensioned Krag drawings other than cartridge and chamber details shown in Mallory's book, which included exterior breech dimensions as well in one drawing. However, Don Hartman's definitive book on Krag Bayonets includes an actual blueprint with details of the "Bowie" bayonet, and I believe the knife bayonet and scabbards as well. Therefore, I believe that the Krags may have had drawings.

Accepting that the trapdoors were the legacy of earlier arms, and built ONLY at Springfield, I believe that they were probably the last of the "built to model and verified by gauge" guns. There were undoubtedly some rough shop level notes, probably prepared by workmen, guiding length of cuts of raw materials, etc, and then after that they put it in the machines and cut until it fit the gauge.

Three books cover the rise of "the American system of manufacture": Felicia Johnson Deyrup's "Arms Making in the Connecticut Valley;" Merrit Roe Smith's "Harpers Ferry and the New Technology" and James Farley's "Making Arms in the Machine Age: Philadelphia's Frankford Arsenal."


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