My Friend Frank Cutler sent me an interesting e-mail about his 40 caliber pistol. Let's let him tell it:
You of course have heard of the 44-40 and 40-65 and the 32-20 and 45-70 etc etc The caliber is always the 1st figure and the grains of powder the 2nd. Well I have a 38-40 Model 1896 Colt that belonged to a lawman from Casper Wy from 1896 to 1914 according to Colt records. I always though that the 38-40 was a necked down 44-40 until one day I took a closer look at the bore and saw that it was much larger than a 38 which is really a 357 cal. While the 38 special cartridge is a bit longer the 38-40 is much bigger around so I checked into it. The 38-40 is the only cartridge that is just the opposite and it really should be called 40-38 so the gun is really 40 Cal and not 38 or 357. I understand it was a really popular caliber in the old west and used by many gunmen.