I have a really nice pellet rifle. I accidentally discovered that if you put a drop of rem oil behind the pellet the oil will diesel under pressure in the chamber and fire it like a rifle. pretty cool actually.
Most powerful springers will diesel for a few dozen shots when they are new. It is not good for them but apparently does no real damage in that time.
Weihrauch, unsure of the spelling, used to make an air rifle with a little port which you swung out, dropped a drop of ether in, closed and it would purposely diesel. Obviously very powerful and it was made to withstand the explosion so I guess it did no damage.