Hello from France. I am a newbie.
I bought a Remington New Model Navy .36 a few months ago.
I give you the characteristics:
S/N #25983 - January 1864
Barrel length = 7” 3/8 with sterling silver front sight
Markings on top of barrel:
PATENTED.SEPT 14.1858
E.REMINGTON & SONS.ILION NEW YORK.U.S.A.
NEW-MODEL
“NEW MODEL” is barely visible.
Anchor on top of barrel near the frame;
S/N under the barrel , lower left of grip (on the steel) with a “T” above ; and inside the two grips (manually).
On the triggerguard’s rear lug : 598 (3 central S/N digits)
Cylinder’s FWD face : P GG (Gens GANSEVOORT, US Navy inspector)
trigger guard rear left : B
Under the barrel ahead of loading lever lug : B
I don’t see any traces of cartouche on the left grip.
My reference book is Donald L. Ware’s Remington Army and Navy Revolvers 1861-1888.
Here are some pictures of this revolver: