• Full guide with 60-second TL;DR video

• Section 1: Weapon & Attachment Unlock List
• Section 2: Best SMG Attachments Analysis
• Section 3: Tuning Insight & Best Practices
• Section 4: Bullet Velocity
• Section 5: Recommended Loadouts, with Tuning

• VEL 46: Unlocked at Player Level 1.
  
  
• MX9: Unlocked by leveling the STB 556 (AR) to Weapon Level 13.
  
  
  • STB 556 (Assault Rifle): Unlocked at Player Level 41.
    
    
• Lachmann Sub: Unlocked by leveling the Lachmann-556 (AR) to Weapon Level 12.
  
  
  • Lachmann-556 Assault Rifle: Unlocked by leveling the Lachmann-762 (BR) to Weapon Level 13.
    
    
    • Lachmann-762 Battle Rifle: Unlocked at Player Level 16.
      
      
• Vaznev-9K: Unlocked by leveling the Kastov-74u (AR) to Weapon Level 13.
  
  
  • Kastov-74u Assault Rifle: Unlocked by leveling the Kastov 545 (AR) to Weapon Level 13.
    
    
    • Kastov 545 Assault Rifle: Unlocked by leveling the Kastov 762 (AR) to Weapon Level 10.
      
      
    • Kastov 762 Assault Rifle: Unlocked at Player Level 23.
      
      
• FSS Hurricane: Unlocked by leveling the FTAC Recon (BR) to Weapon Level 16.
  
  
  • FTAC Recon Battle Rifle: Unlocked by leveling the M4 (AR) to Weapon Level 13.
    
    
    • M4 Assault Rifle: Unlocked at Player Level 1.
      
      
• Minibak: Unlocked by leveling the Kastov-74u (AR) to Weapon Level 13.
  
  
  • Kastov-74u Assault Rifle: Unlocked by leveling the Kastov 545 (AR) to Weapon Level 13.
    
    
    • Kastov 545 Assault Rifle: Unlocked by leveling the Kastov 762 (AR) to Weapon Level 10.
      
      
    • Kastov 762 Assault Rifle: Unlocked at Player Level 23.
      
      
• PDSW 528: Unlocked at Player Level 1.
  
  
• Fennec 45: Unlocked at Player Level 38.
  
  
• BAS-P: Unlocked in Sector A6 of the Battle Pass (Technical Tier 15).
  
  

• FTAC Castle Comp Muzzle: Unlocked by leveling the 556 Icarus (LMG) to Weapon Level 10.
  
  
  • 556 Icarus Light Machine Gun: Unlocked by leveling the M4 (AR) to Weapon Level 18.
    
    
    • M4 Assault Rifle: Unlocked at Player Level 1.
      
      
• FSS OLE-V Laser: Unlocked by leveling the EBR-14 (Marksman Rifle) to Weapon Level 10.
  
  
  • EBR-14 Marksman Rifle: Unlocked at Player Level 1.
    
    
• VLK LZR 7MW Laser: Unlocked by leveling the STB 556 (AR) to Weapon Level 5.
  
  
  • STB 556 Assault Rifle: Unlocked at Player Level 41.
    
    
• FTAC Ripper Underbarrel: Unlocked by leveling the Lachmann-762 (BR) to Weapon Level 6.
  
  
  • Lachmann-762 Battle Rifle: Unlocked at Player Level 16.
    
    

• Muzzle: +Horizontal/Vertical Recoil Control: Straight-up Vertical and Horizontal recoil control is pound for pound, stat for stat, the most powerful form of recoil mitigation (basis: Exact numbers from Vanguard), providing the strongest amount of reduction per point over any other types of mitigation, such as stabilization, steadiness, generic control, or anything of the such. I personally believe this to be the best recoil control attachment in the entire game.
  
  
  • Notice that this was Horizontal first, Vertical second. Attributes of an attachment are listed in order of strength, so if +Horizontal Recoil is listed first and Vertical second, the attachment will provide more Horizontal Recoil Control than Vertical Recoil Control.
    
    
  • What about suppressors?! I would love to include the range-increasing Suppressors, but I find that they incur too much penalty for too little range benefit. SMGs are exceptionally delicate with fast handling.
    
    
• Barrel: Sometimes: SMGs are a very delicate class of weaponry where we try to include Barrels when possible, but SMG Barrels tend to impart heavy mobility penalties that can only be offset by highly-effective mobility attachments that aren't available on most guns. I always tried to include a Barrel to extend range as SMG native ranges are very low, but it simply isn't practical for such marginal gains.
  
  
• Laser: FSS OLE-V / VLK LZR: A penalty-free gain of 10% ADS and Sprint-to-fire with a supplementary bonus to Stability. S-Tier attachment. The “con” to using this is that the laser is visible in ADS; if you are pre-aiming an area you believe an enemy will appear, aim at the wall closest to where they will appear so that your laser is not visible around the corner, and be ready to snap on-target.
  
  
  • What about stability? In Modern Warfare 2, Stability is active at all times, even when firing your weapon; this means that your weapon is always swaying up and down, side to side. I view Stability as a form of “soft recoil control” – and it’s disingenuous to refer to it as control, because it does not affect the amount of kick your weapon has; rather, an unstable weapon has a chance to sway you off-target even with perfect accuracy and recoil control; as such, a stable weapon has a better chance of staying on-target in the heat of battle. More important over medium-range encounters, very important for long-range encounters.
    
    
• Optic: Preference, Otherwise Not Worth It: Try to get used to the Ironsights, but if you find them unbearable, you will be sacrificing something important. The attachment I would recommend cutting to add an Optic would usually be one that increases mobility at the cost of recoil control; these are usually Rear Grips.
  
  
• Stock: Beware of No Stock: While I use a variety of stocks flexed to the guns' needs, beware of the Stockless attachments! The No Stock attachment incurs a severe penalty to first-shot accuracy and a significant overall reduction of recoil control, dramatically exacerbating patterns and significantly increase variance. There is only one weapon I trust to be consistent enough to reap the huge mobility gains but still remaining consistent and controllable enough without a stock.
  
  
• Rear Grip: Sometimes: SMG Rear Grips tend to have a greater impact than AR Rear Grips, for example. A variety of Rear Grips are used to accentuate necessary attributes.
  
  
• Magazine: Extended Magazine: While Fast Hands is indeed king this year, SMGs have a strong need to extend their magazines due to their high rates of fire. I balanced my builds around enhancing the mobility to keep them fast, snappy, and reactive enough to counter the losses from extended mags.
  
  
• Ammunition: Never Worth It: Ammunition types simply do not provide enough benefit to justify an attachment slot when the nature of attachment balancing in this game is such a delicate dance; I liken the balancing of attachments in MW2 to balancing a nuclear reactor – too much heat (mobility) and you’ve got recoil plots akin to a runaway reaction; too much control, and you won’t get any productive amounts of power output. We simply must be using attachments that provide more value. Ammunition is worth it for Longshots! (High Velocity)
  
  
• Underbarrel: FTAC Ripper 56: The Underbarrel slot is absolutely prized with the legendary FTAC Ripper providing incredible amounts of stabilization. This is a key attachment slot for any gun with an undesired amount of horizontal recoil; on almost every recommended build, I highly recommend this supremely powerful attachment to stabilize your recoil and focus it into a largely vertical plot, which is easier to control. The FTAC Ripper also provides an excellent amount of stability, another key stat for more distant engagements, and while this is less important for SMGs, I still tested for overall Recoil Stabilization improvements and found the FTAC Ripper to be the best overall.
  
  
  • Special mention to the FSS Sharkfin 90 – free stability with no downsides. If you are not using an Underbarrel and have a free slot, use the FSS Sharkfin 90.
    
    

• VEL 46
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Medium
    
    
  • The VEL 46, also formally known as the MP7, is a bit of a limited-ranged offering since any barrel makes the weapon an absolute turtle. Expect good handling with excellent recoil, but quickly-decreasing effectiveness at range, as early as 10 meters. To compensate for the lack of range, the handling is accelerated as much as possible while keeping recoil very accurate over range. This MP7 plays like the MP7 you remember from MW19.
    
    
    • Level 11: 50 ADS Kills
      
      
    • Level 19: 15 Hipfire Kills
      
      
    • Level 28: 10 Double Kills
      
      
  • Unlocked at: Player Level 1
    
    

• MX9
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Medium
    
    
  • The MX9, or an SMG variant of a weapon formally known as the AUG, is widely regarded to be a low-damage, low-range, unstable peashooter, but I regard this build as one of my most surprising finds. This build of the MX9 is incredibly accurate with decent mobility, and feels almost comparable to the postnerf STB 556. Play carefully and play intuitively with the inherent 32-round limitation, but otherwise enjoy the absolutely laserlike accuracy.
    
    
    • Level 07: 10 Double Kills
      
      
    • Level 11: 20 Mounted Kills
      
      
    • Level 16: 30 Crouched Kills
      
      
  • Unlocked by: Leveling the STB 556 (AR) to Weapon Level 13.
    
    
    • STB 556 (Assault Rifle): Unlocked at Player Level 41.
      
      

• Lachmann Sub
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Medium
    
    
  • The Lachmann Sub, also formally known as the MP5, is quite a difficult solve - with mobility options limited and the Stockless attachment absolutely skyrocketing the recoil and making it extremely unstable, the focus is aimed towards keeping the recoil pinpoint-accurate while maintaining a respectable level of handling.
    
    
    • Level 07: 10 Double Kills
      
      
    • Level 13: 50 Suppressor Kills
      
      
    • Level 18: 10 Hipfire Kills
      
      
  • Unlocked by: Leveling the Lachmann-556 (AR) to Weapon Level 12.
    
    
    • Lachmann-556 Assault Rifle: Unlocked by leveling the Lachmann-762 (BR) to Weapon Level 13.
      
      
    • Lachmann-762 Battle Rifle: Unlocked at Player Level 16.
      
      

• Vaznev-9K
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Easy
    
    
  • A well-balanced blend of mobility and controllable recoil make the Vaznev a reliable slayer. Universally effective.
    
    
    • Level 06: 50 ADS Kills
      
      
    • Level 09: 10 Double Kills
      
      
    • Level 13: 15 Hipfire Kills
      
      
  • Unlocked by: Leveling the Kastov-74u (AR) to Weapon Level 13.
    
    
    • Kastov-74u Assault Rifle: Unlocked by leveling the Kastov 545 (AR) to Weapon Level 13.
      
      
    • Kastov 545 Assault Rifle: Unlocked by leveling the Kastov 762 (AR) to Weapon Level 10.
      
      
    • Kastov 762 Assault Rifle: Unlocked at Player Level 23.
      
      

• FSS Hurricane
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Easy
    
    
  • An absolutely destructive frenzy of mobility, range, and perfect accuracy, this is without a doubt an S-Tier build of the FSS Hurricane. Almost like a mathematical anomaly, this build performs absolutely beautifully and flexibly, even with the quality of life addition of a 50-round magazine. S-Tier.
    
    
    • Level 06: 50 Suppressor Kills
      
      
    • Level 10: 50 ADS Kills
      
      
    • Level 14: 30 Prone Kills
      
      
  • Unlocked by: leveling the FTAC Recon (BR) to Weapon Level 16.
    
    
    • FTAC Recon Battle Rifle: Unlocked by leveling the M4 (AR) to Weapon Level 13.
      
      
    • M4 Assault Rifle: Unlocked at Player Level 1.
      
      

• Minibak
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Easy
    
    
  • The Minibak, also formally known as the PP19 Bizon, is the only SMG of the bunch I rate to be capable of withstanding the penalties of No Stock. A beautifully controllable recoil plot coupled with excellent handling and capacity make this build an outstanding option.
    
    
    • Level 06: 10 Double Kills
      
      
    • Level 10: 50 ADS Kills
      
      
    • Level 14: 15 Point Blank Kills
      
      
  • Unlocked by: Leveling the Kastov-74u (AR) to Weapon Level 13.
    
    
    • Kastov-74u Assault Rifle: Unlocked by leveling the Kastov 545 (AR) to Weapon Level 13.
      
      
    • Kastov 545 Assault Rifle: Unlocked by leveling the Kastov 762 (AR) to Weapon Level 10.
      
      
    • Kastov 762 Assault Rifle: Unlocked at Player Level 23.
      
      

• PDSW 528
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Medium
    
    
  • The PDSW, also formally known as the P90, is a challenging offering with substantial muzzle climb and blocky visibility; to compensate for the abysmal firing conditions, an optic is added among other balancing attachments to enhance the handling and recoil profile. A very reliable, high-capacity slayer.
    
    
    • Level 11: 50 ADS Kills
      
      
    • Level 20: 15 Hipfire Kills
      
      
    • Level 29: 10 Point Blank Kills
      
      
  • Unlocked at: Player Level 1.
    
    

• Fennec 45
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Hard
    
    
  • The Fennec 45 returns from MW19 and is every bit as demanding of recoil control attachments as its predecessor; fortunately, the barrel solves most of this when supplemented with the superior stabilization of the Phase-3 Underbarrel. While the Fennec will sponge uncountable amounts of bullets at first, the added barrel significantly increases the range and turns the Fennec into a one-frame machine, obliterating your enemies with pinpoint accuracy before you can blink.
    
    
    • Level 10: 30 Crouched Kills
      
      
    • Level 18: 15 Kills from Behind
      
      
    • Level 26: 10 Double Kills
      
      
  • Unlocked at: Player Level 38.
    
    

• BAS-P
  
  
  • Recommended loadout (link)
    
    
  • Difficulty: Easy
    
    
  • The BAS-P is a wonderfully consistent offering with great handling, commendable range and stable recoil, cementing itself as a highly-effective SMG.
    
    
    • Level 07: 15 Hipfire Kills
      
      
    • Level 11: 15 Kills from Behind
      
      
    • Level 16: 50 Suppressor Kills
      
      
  • Unlocked in: Sector A6 of the Battle Pass (Technical Tier 15).
    
    

• Full guide with 60-second TL;DR video

This guide was authored by KRNG XVI | @xvithegreat