Thanks for the pics.
I see the proofs now. They are not located where they were on the guns we see from 1914 onward!
IMO, yes- you have a "Bisley" target gun built well before WW I and numbered in the 44 serial range simply because there was not yet any other series to number it in.
The checkered trigger is original.
I believe the sights are original unless it is determined that these "Bisley" rear sights were added in England.
The 5451 number you mention on the yoke (crane in Colt language) and frame are indeed just assembly numbers applied to keep fitted parts together before the serial numbers were applied. If you look closely at the rear edge of the yoke in the narrow gap between it and the cylinder, you will find a serial number. You have to wipe the gunk off, use a flashlight, and possibly look through a chamber.
If you check for a grip number, it will be in pencil on the top half of the RIGHT grip. Right and left on a gun are determined in
firing position. The number can be degraded by rust, wood oxidation, and oil, so looking in various lighting at various angles might help. Sometimes digital pics will show a number your eye can't pic up. Again, try varying light and angles.
The 455 Mark II Hand Ejector, 1st Model was made in 1914-1915 in serial number range 1 - 5,000.
Gary,
you are correct on the WW I contracts for the Brit government, but we now know there were quite a few 455s made before the War
in the 44 serial range.
These Bisley Targets are one variation, and a few dozen 5 inch 455s are known to have shipped to Canada commercially in 1912 and possibly before.
This model was designed to shoot 455 Webley Mk II ammo. ......................Calibers for the Webley revolver were quite confusing, with the early calibers including 476 Eley, 476 Enfield MKIII, 455 Colt, 455 Revolver MKI, 450 Revolver, 450 Short, 450 Adams and the 450 Colt. All of these calibers were said to fire in Webley revolvers, but the shorter chambers of the S&W 455 revolvers allowed only a few to work.
That is not correct.
ALL S&W 455s I have ever handled had the LONG chambers of the 455 Mk I. That makes sense cause you hate to get stuck in some far corner of the Empire with only the old, long ammo!