Mason left Remington Arms in 1866 to work for Colt as the Superintendent of the armory. Along with
Charles Richards, Mason patented designs to convert percussion revolvers into rear-loading metallic cartridge revolvers. Those converted revolvers are identified as the "Richards-Mason conversion".
[3] After working on these conversions, Mason began work on Colt's first metallic cartridge revolvers in 1871: the
Colt Model 1871-72 “Open Top” revolver was the third such pistol, following the .41 caliber House Pistol and the .22 caliber seven-shot Open Top. The Open Top .44 was a completely new design and the parts would not interchange with the older percussion pistols. Mason moved the rear sight to the rear of the barrel as opposed to the hammer or the breechblock of the earlier efforts. The caliber was
.44 Henry and it was submitted to the
US Army for testing in 1872. The Army rejected the pistol and asked for a more powerful caliber with a stronger frame. Mason redesigned the frame to incorporate a top strap, similar to the Remington revolvers and placed the rear sight on the rear of the frame. The first prototype was chambered in .44 rimfire, but the first model was in the newest caliber known as the
.45 Colt. (Wiki)
3rd Model (Merwin Hulbert) – Retaining the general look of its predecessors, the 3rd model had significant changes. The first was the addition of a top strap over the cylinder, which added to the strength of the design.
Early on, Colt was at a disadvantage. Many of the company's "open top" pistols were inherently weaker than full-framed revolvers such as the Remington Model 1858.
In 1870 when the Army tested Colt's latest revolver, they complained that the .44 rimfire round was too weak and that the open top design was too fragile.
So, shortly thereafter, Colt produced a pistol that fired a more powerful centerfire cartridge and had a stronger, more durable frame. William Mason, along with fellow Colt gunsmith Charles Brinckerhoff Richards, began to rework the 1870 design by incorporating a top-strap to increase the strength of the revolver's frame and remove the need for a barrel wedge, one of the biggest weaknesses of previous Colts.
“Yes, it would be the Remington. Matt had enough money to purchase the sixgun, powder, caps, lead, a bullet mold, and even a Slim Jim holster and wide belt. Matt had worked very hard that summer and now he was being rewarded. Little did he know what the not very distant future held for so many young boys all over the country. In just a very few short months he would be wearing that Remington when he joined the Union Army.
The Remington was available both as an 8” .44 New Model Army and a 7 1/2” .36 Navy Model. Percussion Colts were more readily available and in a greater profusion of models but the Remington cap-n-ball sixgun had several advantages over the Colt. The frame of the Remington was solid with a barrel that was permanently screwed into the frame while the Colt sixguns were all open-topped with removable barrels that were held in place by two small pins at the bottom of the front of the frame and a wedge pin that entered the barrel assembly from the side. A town marshal using his Colt to smack to a hard headed cantankerous drunk on Saturday night would surely bend his gun but the solidly built Remington would be no worse for wear.
The Remington also had a better sighting arrangement with a rear sight that was a hog wallow through the top of the frame mated up with an easy to see front sight. The Colt carried a brass front sight while the rear sight was a notch in the cocked hammer. The Colt did have two great advantages. Most pistoleros found it to be quicker from leather and slightly faster to handle with its easier to reach hammer and more comfortable grip, and it also would shoot longer without jamming from fouling. However, no less a legend than Buffalo Bill Cody said his Remington never failed him.“ Writer John Taffin
I’ll grant you this. The gun fouls easily. If it is the cylinder pin size , it is a problem. The overall solid , top strap frame design is superior though and is why the colt company went to it. Sam however was a proud man and stood by his open top while he was alive.
I also suspect colt’s popularity might be cultural. It is touted as the gun that won the west and was the issued in the confederacy , mostly knock offs made in the south, and coveted by it’s soldiers although they did have remingtons and every other gun they could get their hands on.