After finding one of these 3.2" field artillery rifles at Ft. Washington on the Potomac River last fall, Mike and I posted the following. I believe you will understand WHY they needed a "Flash Shield" after reading about the construction details of the Model 1890.
Re: Cannons, Like Gold, Are where You Find them
« Reply #2 on: December 01, 2008, 06:26:52 PM »
Thanks Allen, we have always like the lines on this gun as well. We suspect that the purpose of the plastic clad small dia, steel cable was to keep people from opening the breech block while the gun was on display in lieu of welding it closed. A little peek at that real short chamber was what we needed and we left the breech block Exactly the way we found it. All three of these US 3.2-INCH FIELD GUNS, the MODELS 1885, 1890, and the 1897 were designed before the real designers retired and the "add-a-gadget" boys took over as they certainly did in WWI.
Interesting features on the gun we discovered were the axial vent
on this Model 1890 and the smaller chamber of the 1897 which was designed for smokeless powder. Almost all Model 1890 guns had a liner installed which reduced their chamber size by over one-half to upgrade them for use with smokeless. Only the Model 1885 has the radially placed vent
like an Ordnance Rifle does. The axial vent, like a 12 pdr. Whitworth, puts the vent bushing right in the center of the obturator spindle and is held in place by threads fore and aft. The obturator is an asbestos pad soaked completely in beef tallow and covered with canvas. Almost a duplicate of the De Bange Obturator used in many WWI guns. De Bange's had a piece of tin over the canvas for durability, but functioned similarly.
An axial vent, like the 1890's, with an attitude similar to a mortar vent, needs a Hot Gas and Friction Primer Deflector
to protect the artillerymen serving the piece.
The recoil brakes on this gun are very interesting.
A photo showing the recoil brakes in the disengaged position. We could guess, but we really don't know how they function. Maybe Artilleryman can tell us how they work?
Tracy and Mike