SilencerCo does not list the PT99 as being compatible with this barrel. I was also unable to find any information regarding the PT99 using Beretta 92 barrels. Although they are similar, I cannot confirm that Beretta 92 barrels will be compatible. For this reason, I would recommend contacting SilencerCo or Taurus directly for more information.
It will work.
The only difference between a Taurus PT92 and a PT99 is the PT99 has adjustable rear sights, otherwise they are the same gun.
With that said, I’ve personally, successfully installed this exact barrel in numerous Taurus PT92’s, Taurus PT99’s, and Beretta 92’s & M9’s, with a few older Taurus models requiring very minor ‘fitting’. To do this I place a small amount of 600 grit lapping compound on the contact points of the barrel (keep it out if the barrel & chamber) and just work the slide back and forth until it runs smooth. Don’t forget to completely clean out the lapping compound when you are finished!
Here is a compatibility chart for you.
Beretta 92FS/M9 & Taurus PT92/99 interchangeable parts:
—Barrel & Locking Block Assembly
—Guide Rod & Recoil Spring
—Take Down Lever
—Slide Stop/Release
—Trigger Return Spring
—Hammer Spring
—Grip Frame Bushings
—Hammer Spring Plug
—Grip Screws — Beretta style grip screws will work on PT92's if you install 3 more grip bushings into the 3 larger holes in the frame, you still have to use PT92 grips.
Not interchangeable:
—Take Down Button (pre 1991 non-decocker Taurus models were the same as Beretta, post 1991 Taurus models flipped the side that holds the spring.
—Mag Catch / Mag Release
—Grip Panels