Two tools were recently examined with elongated block-like ends. However, unlike the 38-50 tools, these have what appear to be original casting chambers cut into the blocks. The top panel of the composite image below shows what is believed to be an early variation #3 tool in 38-50 M tool for comparison above a tool marked 44 C.M.R & W.C.F. The second panel in the image shows the top view of the tools with the 38-50 on the top, the 38 C.M.R. & W.C.F. tool in the middle, and the 44 C.M.R & W.C.F. tool at the bottom. The third panel is a little closer view showing how the "blocks" on the 38-50 tool (left) are slighter narrower than those of the 38 C.M.R & W.C.F. (middle) and 44 (right) tools. Also, the 38-50 tool has the capper back by the bullet sizer while the other two tools have it on the end of the "blocks". The next series of vertical panels shows the actual caliber markings from the tools; the final two images show the bullet profiles from the 38 C.M.R. & W.C.F. and 44 tools.

The fact that at least some of these tools have what appear to be factory cherried casting chambers suggest the possibility that they may represent a early variants of #4 tools. Ed Curtis mentioned over on the message board that the "C.M.R. and W.C.F." stands for "Colt Magazine Rifle and Winchester Center Fire", and I suspect he is correct in that.