Gents and Madams,
To continue on the subject of the .43 Spanish.
The Remington Rolling Block is completely devoid of any outward markings indicative of it being issued to any foreign military. Full stocked, with bayonet lug and the duplicate Autrian Werndl rear sight, this rifle looks to be something that Remington could have sold on the civilian market because it was a contract overrun.
A CerroSafe chamber castings provides the following:
Rim diameter .650.
Rim thickness .090.
Diameter in front of rim .524.
Diameter at shoulder .515.
Diameter at rear of neck .468.
Diameter at front of neck .462.
Length from base to shoulder 1.590.
Shoulder length .150.
Length from base to rear of neck 1.740.
Overall Length (WOW) is 2.580.
Other then the extra length of the neck, the dimensions are in line with those given for .43 Remington and .43 Spanish as delineated in Ken Howell's Custom Cartridges, pages 349 and 350.
The chamber cast reflects a very slight extension of the rifling the full length of the neck. A barely discernable, (protruding) line about .001" rotating in conjunction with the existing rifling.
In addition to the excessive neck length a tapered .100" long leade exists prior to the five groove rifling. The five groove rifling is difficult to measure for an actual bore diameter. Somewhere between .439 and .441 is my guesstimate.
For sure the chamber IS NOT a .44-77 Remington.
After having read Mike Venturino's Buffalo Rifle Book and about every thread on Shooter's.com, the conclusion will be to purchase some .43 Spanish (Basic) brass from Buffalo Arms.
With both LEE and RCBS dies available, surely some decent ammunition can be built that will take up the entire neck area of the chamber and allow for proper sealing without the bullets obturating into the chamber neck area?