Cliff notes: Some early Steyr M9's suffer from a thin hardening that tends to deform the slide with suppressor use. The solution: After a lot of correspondence, it was decided to send the Steyr slide and internals to IGB for them to inspect. After some testing, they came up with a repair to mill the damaged steel on the top of the slide, and re-harden the unit using their Plasma hardening process (much tougher than the factory Tenifer). Next, a custom barrel was machined to fit the new slide area. I'm told the gun now shoots better than factory. I must thank user Wulf for his input on this matter - he's a great man!