The M9 returns in Call of Duty: Modern Warfare 2 as a standard sidearm for the Rangers, and TF141 on some levels. The M9's appearance seems to have been slightly improved from Call of Duty 4, as it seems to be slightly shinier and a deeper black. An M9 Akimbo can be found in The Gulag in the armory, where the player is told to equip the Riot Shield. It is also occasionally dropped by the divers or the airport security guard in the Museum as M9 Akimbo.
The M9 now has higher minimum damage, bullet penetration, and fire rate than its counterpart in Call of Duty 4, but is unlocked at Level 46, and suffers from higher recoil. It is the default handgun used for Last Stand when the player is using a secondary weapon that is not a handgun or the M93 Raffica, regardless of the player's level, and does not have any attachments.
Even while using ADS, the M9 recoils slightly side-to-side and somewhat upwards. Because of this, it is nearly impossible to fire accurately at range, unless it is fired slowly, letting the recoil settle. However, at close range it can be fired as quickly as the user can push the fire button.
The M9 no longer retains its advantage over the USP .45 with higher hip fire accuracy, as both are the same, nor is it relatively accurate compared to the other handguns. The USP .45 has a slightly longer 3 hit kill range, with the disadvantage of a 3 round smaller magazine, and higher recoil.
If used with Stopping Power on Hardcore, the M9 can obtain one-shot kills at any distance, like the USP .45. This makes it a highly effective weapon, and can be good for completing the M9's challenges.
Due to a glitch in the game, the M9 Expert challenges stay locked until the Desert Eagle is unlocked at level 62. Another glitch is the fact that, with an attached silencer, players will still appear on the radar when firing the M9. It shares this problem with the MG4 and the M240. The only effective suppressed pistol, therefore, is the USP .45.