difference in a 22 tcm and a 221 fireball

What is the difference in a 22 tcm and a 221 fireball. To me they are about the same. Bought are made from a 223 necked down to a 22.??

The TCM was designed as a pistol round to be fired in a semi-auto pistol.

They do make a rifle.

The Fireball is a short rifle round shot out of a bolt action pistol. The 22 TCM is a pistol round that was designed to fire out of a modified 1911, that it can be fired from a rifle chambered for the 22 TCM does not make it the equal of what is accentually a rifle round. The OAL of the Fireball is over.5" longer than a 22 TCM

The 221 was originally made by shortening up a 222. Not that it makes a lot of difference. The 221 also operates at higher pressures than the 222 making it a bit of an over achiever for its size. 40 grain loads in the 221 can surpass 3,400fps out of a 22" rifle and is darn near right up there with a 222. The 22tcm from the same length barrel is running about 2,700fps.

The 221 has a case length of 1.40" vs 1.022 for the 22tcm. Quite a difference there actually.

I have had 221's for over 25 years now and its one of my favorite rounds. I run it in rifles and xp100's. After all that , I have been giving the tcm some serious thought though. I think it would make a cool little round and be pretty cheap to load for. And 2,700fps is more than enough for most varmnints out to a couple hundred yards.