The M13 is not an absolutely top-tier weapon, but it is one of the nicest feeling and easiest to use assault rifles. This is thanks to a good rate of fire and very low recoil. It feels like a laser, and it's effective out to about 65/70 meters. You'll find that the M13 has great versatility, so in this build we're going for a Ghost loadout and build it as a do-it-all rifle.
If you're interested in how the M13 stacks up against weapons in its class, check out our complete Warzone Assault Rifle tier list.
The Best M13 Attachment Setup
| Component | Attachment | Unlock Level |
| Muzzle | Monolithic Suppressor | 60 |
| Barrel | Tempus Marksman | 56 |
| Optic | VLK 3.0x Optic | 31 |
| Underbarrel | Commando Foregrip | 18 |
| Magazine | 60 Round Mags | 53 |
We're looking at a fairly standard Warzone build for the Modern Warfare 2019 ARs. The Monolithic Suppressor keeps us off radar and boosts range, the Commando Foregrip reduces recoil and is more useful than other underbarrel attachments, and the Tempus Marksman barrel gives us the best bullet velocity for tracking targets over range. Choose whichever optic you like best, we chose the VLK because this build is optimized for a range best suited to 3x magnification strength. And high capacity mags are essential for every Warzone build.
The Best Secondary, Grenades & Perks For An M13 Loadout
The Best Secondary Weapon for the M13
With ground loot being fairly decent in Caldera so far, you don't need a particularly strong secondary. The AMP63 should be more than enough to keep you covered in those emergency situations. It's got decent range and a higher TTK than other sidearms.
The Best Equipment For The M13
| Lethal | Throwing Knife |
| Tactical | Heartbeat Sensor |
Given that this is an M13 loadout guide, and you can't use the weapon in Vanguard Royale anyway, we won't bother with the normal restrictions that apply to that mode. That means Heartbeat Sensors are back, naturally, although for tactical equipment, we've stayed with the ever-popular Throwing Knives to thirst downs.
The Best Perks for the M13
| Perk 1 | Cold-Blooded |
| Perk 2 | Ghost |
Perk 3 | Combat Scout |
This is the hard meta for perks right now. Unfortunately, the other perks just don't stack up against Combat Scout on Caldera, and Cold-Blooded is the only counter to it. So those two are a must, plus the ever-popular Ghost, which will keep us off those pesky heartbeat Sensors and UAVs.
That was your complete guide to the M13 in 2022. But if the M13 is just feeling too damn weak for you, then maybe you want to check out one of the newer weapons instead. Why not the STG? Or maybe the Bren?