Haven't heard about the 221 Remington Fireball in a long time.I almost forgot about it.If I remember correctly Remington's XP 100 was chambered in that little round.
For information the Speer manual Number 13 has it under the handgun cartridges.It was introduced back in 1962.The 221 is basically a shortened 222 Remington.Factory ammo using a 50 grain soft point chrongraphed at 2620 FPS from a 10 3/4" bbl. Only time will tell if it comes back or not..I was correct about the Remington XP 100 and this cartridge.The were a awesome combination.

Ruger Redhawk

..... A Proud NRA Life Member since 1977 .....Ruger Redhawk