.45 Peabody Sporting anomaly

In my collection there’s a .45 Peabody Sporting (called .45-50-290 by James Grant) that’s been in my collection for years. I’d always thought it a typical UMC center fire large caliber rifle cartridge until I picked it up a day or two ago. It has the typical folded-head construction with a raised circle around the primer; the primer itself is domed and made of brass. What finally caught my attention is the fact the primer isn’t the typical big (.250 in. diameter) UMC brass type but is about the size of the usual Boxer “large rifle” type (.210 in. nominal). The 1946 Braucher catalog Ron put up on this site recently lists a “45-50-290 Peabody sporting, BN, PP lead, WRA plain” while an old Platt Monfort catalog (circa 1942) offers a “45 Peabody Sporting UMC, PP, unmarked.” So I wonder: is my specimen by UMC with the “wrong” primer? Is it the WRA? No reasonable suggestion will be turned down without serious deliberation. Thanks, JG

If you are able to post a picture of the head, it can be determined if it is U.M.C. or W.R.A… M. Rea

M.D.: Unfortunately I can’t come up with an image. To me the cartridge has an appearance like the typical U.M.C. large-caliber centerfire of the late 1870s except for the smaller rounded brass primer, the size of the primer appearing to be about the same as the .210 Boxer. When I noticed this one I rechecked all my other “U.M.C.” types to make sure I hadn’t overlooked others like this, but those had the big Berdan primer. Do wish I could come up with a pic for you. Thanks, J.G.