I also have in my collection a 14" Thompson Contender barrel in 375 Winchester
So I looked in a reloading book and I see that the two cases are nearly identical. And sure enough, in all three firearms, both cartridges fit with no issues.
Very strange that the 375 is a bit shorter than the 38-55. This allows a 375 case, at upwards of 52,000CUP to fit and fire in a 38-55 with a limit of 28,000CUP. I would have thought Winchester would have made the 375 longer so this couldn't accidentally happen. Especially in older, Black Powder, guns...........
I measured five cases of each:
The 375Win average 146.6g and the 38-55 cases average 136.0g in weight
The 375 length average 2.006" and the 38-55 average 2.075"
Just above the rim, both cartridges are .414 and at the mouth, both cartridges are.390 (new, unfired brass)
I would imagine it is totally safe to fire 38-55 cartridges in my TC 375Win barrel...........(but certainly not the other way around)
![Image](http://images18.fotki.com/v438/photos/2/36012/11139570/P1030488-vi.jpg)
![Image](http://images43.fotki.com/v680/photos/2/36012/11139570/P1030490-vi.jpg)
Anyone have any experience with this?