Hi: new to site
I have came across a Mass. arms co bullet mold. It is for round ball and a conical bullets and measures about .405. It is made of brass. My limited research leads me to believe it was made for the wesson & Leavitt paton revolver which was made by Mass armes co in 1850 & 51. when colt sued them for paton infringement the production stopped.
If anyone out there has any additional info I would like your input.