Back in the early 1960's I worked in the metallurgy lab. of a place that made cylinders, among many other items. They were seamless deep-drawn 4130, quenched, and tempered at 1000F.

For proof of a big lot of them they fired a .50 cal. machine gun bullet at one that was pressurized with air (don't recall the PSI). They used a series of plywood baffles set at an angle to turn the bullet sideways before it hit the cyl. No shrapnel was allowed-cyl. had to stay in one piece.

There really isnt much that can go wrong with cylinder besides actual damage caused by user, being dropped, ect.