It is an interesting point and valid as after owning three hornets and looking down many a hornet barrel to confirm what I learnt, hornet is unique in that it produces water vapour like all cartridges but not enough heat to warm the barrel with just one shot leading to droplets forming just forward of the chamber causing damage.
Check before you buy.
It also does not mean a hornet is finished if there are pits there. It's just a unique trait to check for.