I finally measured my "Big Ten". As stated it is an E grade rod cocker with pivot lever, SN 10,515. Measuring between the end of the sideplate & the beginning of the sculpting of the bar I get the following dimensions. Bar width is 1.680" & depth is .870". It is thus about .040" wider than any off my 12 gauge guns but no deeper. I note that Bob's 8 gauge is slightly wider than my 10 as is one of his 12's. Personally I call a change of .040+" a wider bar, others can differ if they like. All of my 12's are within a .010" range.
This gun has bushed firing pin holes thus making an accurate measurement of spacing a bit difficult. Apparently there is a spring behind the pins holding them out as even with the hammers cocked they could not just be pushed back inside. The "Rebound" screws are set so they are about flush with the breech face. I measured the C/L's of the chambers of the barrels at breech & got 1.212". I set my calipers to this measurement & placed them on the firing pins & they looked spot on as best as I could see.
Standing breech width measured 2.560" with a height of 1.312". Barrels fit very closely. One thing I found which surprised me was that I set a small square head on the Water table & pushed the blade up against the standing breech. With contact at the top there was a slight gap at the bottom, thus the breech is very slightly tilted forward. I did not try to measure the amount.
This gun has a pistol grip stock & long trigger guard tang which extends down to the grip cap, which unfortunately is missing. Engraving is the early scroll design, no animal or bird scenes. It does have the 1887 patent date so made after that, likely around 1889 or so.
PS; On further consideration I do not believe there is a spring behind the firing pins. I believe rather the pins have a flange on them which abuts a step in their hole, thus providing a gas seal to prevent gas from a pierced primer blowing back into the action. The "So Called" rebound screws on these guns do not stop the hammers themselves but the main spring leaf which bears against the hammer. The hammer thus puts no pressure on the firing pin to hold it forward after the main spring is stopped. All in all a very good workable arrangement.
Last edited by 2-piper; 02/24/18 10:49 PM. Reason: Added Info
