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Re: Reliability of .50-70 models

Posted by D Miller on Thursday, 13 July 2017, at 1:45 p.m., in response to Re: Reliability of .50-70 models, posted by David on Thursday, 13 July 2017, at 2:28 a.m.

This post roused up my curiosity. I took an unfired .50/70 case drilled out the primer pocket and threaded it for 3/8-16. Put a set screw in so the length of the brass could then be adjusted. Than turned off its rim and removed its taper down to a .523" diameter cylinder. My intent was to show a comparison. Disregarded throat erosion in this experiment. I tried action closure on 4 trapdoors, 1 sharps and 5 Remington's. The trapdoors ranged from 2.045" to 2.125". The sharps 1.990". The Remington's 1.950" to 2.040". I know this experiment is far from being exact and totally scientific but out of 10 pieces tried the chambers did vary as much as .175" in length. The shortest chamber was the New York Remington 1871 carbine and the longest was and 1866 trapdoor. It appears that if you are looking for the longest brass that will fit in a specific chamber it should be done for that chamber alone. Unless you have target sights or a scope on a specific rifle it probably is not practical to exceed the standard 1.750".

Trapdoors: M66 2.125", M68 2.045", M70 2.050", M70 carbine 2.010"

Sharps: M70 trial 1.990"

Remingtons: M70 trial 2.015", M70 Navy type 1 2.005, M70 Navy type 2 1.950, M71 2.040, M71 NY carbine 1.985


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