I've had 3 DW's made in Monson. Neither has had a model number listed on the frame, nor anyother I have seen (including .357's and .22's). DW used to list them all as small framed. Everything was the same as far as parts were concerned, except for the bores of barrels and chambers of cylinders. I think this same style of cataloguing applied to the large frame and the super mag framed revolvers.
As to the catridge not fitting, the DW may have tighter chambers. Try factory ammo or use one a the factory crimp dies (like Lee). Or highly unlikely, but (not to insult your intelligence) could the cylinder be a .32 caliber?