My fav is probably the 32 SWL loaded warm in my model 31 4" barrel. 9.3x62 is an excellent round for North America. I just traded for a 8x68. A very cool semi-big rifle.
My favorite is the 38-50 Remington Hepburn. Take a 30-40 Krag case and blow it out to .375, fill it with Black Powder and have fun. I have two Hepburns chambered in 38-50.
40-90 Sharps Necked. I don't have the rifle for it any more, but that was one hell of a long range round. I like the 44/40 in a '73 Winchester for plinking and jackrabbits.
Quite a few. .44 Russian, .455 Webley Mk I and MkII ,.25-20 Winchester,.25-36 Marlin ( necked down from .32-40 Marlin-Ballard),.32-40 Marlin-Ballard, .38-55
8X56R in my straight pull Styer carbine, 32-20 in my M16(came with 2 cylinders), 405 Winchester(Teddy's big medicine) in my Browning 1885, and 30-40 in my 1898 Krag Carbine-was my maternal grandfather's, he carried it up the hill with Teddy's boys(they were supposed to be cavalry so they had carbines instead of rifles).
The .22 Winchester Automatic. Ammo was getting scarce in the 1950s. The last box we had was so old that there was almost no report when the rifle fired, the action of the rifle reloading was louder than the shot. That ammo was used in the Winchester .03. I always thought about replacing it with a Winchester 63, but the price of those was more than I was willing to pay. When I was a teenager I had a chance to buy a Winchester in .401 at a furniture store where I worked. My Dad talked me out of it. I'm not sure whether he did me a favor, but he did say ammo was getting hard to find.
I kind'a like the 9mm Browning long (9x20) for my Husqvarna m07.
Obsolete and hard to find despite it being a military round here in Sweden in the -50th.
9.3x74R, in my single shot stalking rifle, I like shooting it but the RWS ammo is expensive and hard to get. I have to breakdown and buy a set of dies.