This is a list of small arms whose manufacturer or name (in the case of no known or multiple manufacturers) starts with the letter M—including pistols, shotguns, sniper rifles, submachine guns, personal defense weapons, assault rifles, battle rifles, designated marksman rifles, carbines, machine guns, flamethrowers, multiple-barrel firearms, grenade launchers, anti-tank rifles, and any other variants.
- M1 carbine (US – semi-automatic carbine – .30 carbine)
- ACS Hezi SM-1 (US, Israel – semi-automatic carbine – .30 carbine: M1 carbine Variant)
- M1A1 carbine (US – semi-automatic carbine – .30 carbine)
- M1A2 carbine (US – semi-automatic carbine – .30 carbine)
- M1A3 carbine (US – semi-automatic carbine – .30 carbine)
- M2 carbine (US – carbine – .30 carbine)
- M3 carbine (US – semi-automatic carbine – .30 carbine)
- M1 Garand rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1 rifle (US – semi-automatic rifle – .30-06 Springfield/7.62×63mm)
- M1D rifle (US – sniper rifle – .30-06 Springfield)
- M1E1 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E2 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E3 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E4 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E9 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E5 carbine (US – semi-automatic carbine – .30-06 Springfield)
- M1E6 sniper rifle (US – semi-automatic sniper rifle – .30-06 Springfield)
- M1E10 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E11 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E12 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E13 rifle (US – semi-automatic rifle – .30-06 Springfield)
- M1E14 rifle (US – semi-automatic rifle – 7.62×51mm NATO)
- T1 rifle (US – semi-automatic rifle – .30-06 Springfield: Prototype)
- T1E1 rifle (US – semi-automatic rifle – .30-06 Springfield: Prototype)
- T1E2 rifle (US – semi-automatic rifle – .30-06 Springfield: Prototype)
- T20 automatic rifle (US – battle rifle – .30-06 Springfield)
- T26 carbine (US – carbine – .30-06 Springfield)
- T31 rifle (US – rifle – .30-06 Springfield: Prototype)
- T35 rifle (US – rifle – 7.62×51mm NATO)
- M14 rifle (US – battle rifle – 7.62×51mm NATO)
- M14 designated marksman rifle (US – semi-automatic designated marksman rifle – 7.62×51mm NATO)
- M14E1 (US – battle rifle – 7.62×51mm NATO: Prototype)
- M14A1 (US – squad automatic weapon – 7.62×51mm NATO)
- M14E2 (US – squad automatic weapon – 7.62×51mm NATO: Prototype)
- M14M (US – semi-automatic battle rifle – 7.62×51mm NATO)
- M14NM (US – semi-automatic battle rifle – 7.62×51mm NATO)
- M14 SMUD (US – semi-automatic battle rifle – 7.62×51mm NATO)
- M15 (US – squad automatic weapon – 7.62×51mm NATO)
- M21 sniper rifle (US – semi-automatic sniper rifle – 7.62×51mm NATO)
- M39 EMR (US – semi-automatic designated marksman rifle – 7.62×51mm NATO)
- Mk 14 Mod 0 (US – designated marksman rifle – 7.62×51mm NATO)
- M14 EBR-RI (US – designated marksman rifle – 7.62×51mm NATO)
- M14 Tactical (US – designated marksman rifle – 7.62×51mm NATO)
- Mk 14 Mod 0 SEI (US – designated marksman rifle – 7.62×51mm NATO)
- Mk 14 Mod 1 (US – designated marksman rifle – 7.62×51mm NATO)
- Mk 14 Mod 2 (US – designated marksman rifle – 7.62×51mm NATO)
- M24 sniper rifle (US – bolt-action sniper rifle – 7.62×51mm NATO)
- M24A1 (US – bolt-action sniper rifle – 7.62×51mm NATO)
- XM24A1 (US – bolt-action sniper rifle – .300 Winchester Magnum: Prototype)
- M24A2 (US – bolt-action sniper rifle – .300 Winchester Magnum)
- M24A3 (US – bolt-action sniper rifle – .338 Lapua Magnum)
- M2010 (US – bolt-action sniper rifle – .300 Winchester Magnum)
- M40 (US – bolt-action sniper rifle – 7.62×51mm NATO)
- M40A1 (US – bolt-action sniper rifle – 7.62×51mm NATO)
- M40A3 (US – bolt-action sniper rifle – 7.62×51mm NATO)
- M40A5 (US – bolt-action sniper rifle – 7.62×51mm NATO)
- M40A6 (US – bolt-action sniper rifle – 7.62×51mm NATO)
- M60 (US – general-purpose machine gun – 7.62×51mm NATO)
- T161 (US – general-purpose machine gun – 7.62×51mm NATO: Prototype)
- M60B (US – general-purpose machine gun – 7.62×51mm NATO)
- M60D (US – vehicle mounted general-purpose machine gun – 7.62×51mm NATO)
- M60C (US – aircraft mounted general-purpose machine gun – 7.62×51mm NATO)
- M60E1 (US – general-purpose machine gun – 7.62×51mm NATO: Prototype)
- M60E2 (US – vehicle mounted general-purpose machine gun – 7.62×51mm NATO)
- M60E3 (US – general-purpose machine gun – 7.62×51mm NATO)
- M60E4 (US – general-purpose machine gun – 7.62×51mm NATO)
- M60E6 (US – general-purpose machine gun – 7.62×51mm NATO)
- M89SR sniper rifle (State of Israel – 1980s – semi-automatic sniper rifle – 7.62×51mm NATO)
- M110 SASS (US – semi-automatic sniper rifle – 7.62×51mm NATO)
- M110 CSASS (US – semi-automatic sniper rifle – 7.62×51mm NATO)
- M202 FLASH (US – multiple-barrel grenade launcher – M235 Incendiary TPA)
- M202A1 Flash (US – multiple-barrel grenade launcher – M235 Incendiary TPA)
- M1014 (Italy – semi-automatic shotgun – 12 gauge)
- MAG-7 (Republic of South Africa – subcompact pump-action shotgun – 12 gauge)
- MAG-7 M1 (Republic of South Africa – pump-action shotgun – 12 gauge)
- Maadi 920 (Egypt – semi-automatic pistol – 9×19mm Parabellum)
- Maadi Griffin (Egypt – single-shot bolt-action anti-materiel rifle – .50 BMG)
- Maadi MISR-10 (Egypt – semi-automatic rifle – 7.62×39mm)
- Magnum Research
- Pistols
- Revolvers
- Magnum Research BFR (US – single-action revolver – Various)
- Magnum Research BFR Long Cylinder (US – single-action revolver – .30-30 Winchester, .375 Winchester, .38–55 Winchester, .444 Marlin, .45 Colt, .45–70 Government, .45–90 Winchester, .450 Marlin, .460 S&W Magnum, .50 Beowulf, .50 JRH, .500 S&W Magnum)
- Magnum Research BFR short cylinder (US – single-action revolver – .22 Hornet, .218 Bee, .44 Remington Magnum, .45 ACP, .45 Winchester Magnum, .454 Casull, .475 Linebaugh, .480 Ruger, .50 Action Express, .50 GI, .50 JRH)
- Rifles
- Magpul Industries
- submachine guns
- Magpul FMG-9 (US – folding submachine gun – 9×19mm Parabellum: Prototype)
- Magtech Model 7022 (US – semi-automatic carbine – .22 Long Rifle)
- Magtech Doorbuster (US – pump-action shotgun – gauge)
- Mamba (South Africa – semi-automatic pistol – 9×19mm Parabellum)
- Mambi AMR (Cuba – semi-automatic anti-material rifle – 14.5×114mm)
- Manufacture d'armes de Bayonne
- Pistols
- MAB Model A (France – subcompact semi-automatic pistol – .25 ACP)
- MAB Model B (France – subcompact semi-automatic pistol – .25 ACP)
- MAB Model C/D (France – semi-automatic pistol – .32 ACP, .380 ACP)
- MAB Model E (France – semi-automatic pistol – .25 ACP)
- MAB Model G (France – compact semi-automatic pistol – .22 Long Rifle)
- MAB Model R (France – semi-automatic pistol – .32 ACP)
- MAB Model P8 (France – semi-automatic pistol – 9×19mm Parabellum)
- MAB PA-15 (France – semi-automatic pistol – 9×19mm Parabellum)
- Manufacture d'armes de Châtellerault
- Machine Guns
- MAC 24/29 (France – light machine gun – 7.5×54mm French)
- MAC 24/29D (France – light machine gun – 7.5×54mm French)
- MAC-31 (France – light machine gun – 7.5×54mm French)
- MAC-58 (France – heavy machine gun – .50 BMG: MAS AA-52 Variant)
- Pistols
- MAC-50 (France – semi-automatic pistol – 9×19mm Parabellum)
- Manufacture d'armes de Saint-Étienne
- Revolvers
- MAS 1873 (France – single-action revolver – 11mm French Ordnance)
- Rifles
- MAS G3 (France – battle rifle – 7.62×51mm NATO: HK G3 Variant)
- MAS HK33 (France – assault rifle – 5.56×45mm NATO: HK33 Variant)
- MAS-36 (France – bolt-action rifle – 7.5×54mm French)
- MAS-36 CR39 (France – bolt-action rifle – 7.5×54mm French)
- MAS-36 FR-G2 (France – bolt-action designated marksman rifle – 7.5×54mm French)
- MAS-36 LG48 (France – bolt-action rifle – 7.5×54mm French)
- MAS-36/51 (France – bolt-action rifle – 7.5×54mm French)
- submachine guns
- MAS-38 (France – submachine gun – 7.65×20mm Longue, .32 ACP)
- MAS-49 (France – semi-automatic rifle – 7.5×54mm French)
- MAS 49/56 (France – semi-automatic rifle – 7.5×54mm French)
- MAS Type 62 (France – battle rifle – 7.62×51mm NATO)
- FA56 (France – battle rifle – 7.62×51mm NATO)
- FA59 (France – battle rifle – 7.62×51mm NATO)
- MAS-54 (France – battle rifle – 7.62×51mm NATO)
- MAS-55 (France – battle rifle – 7.62×51mm NATO)
- MAS modèle 1935 (France – semi-automatic pistol – 7.65×20mm Longue)
- MAS modèle 1935A (France – semi-automatic pistol – 7.65×20mm Longue)
- MAS modèle 1935S (France – semi-automatic pistol – 7.65×20mm Longue)
- MAS modèle 1935S M1 (France – semi-automatic pistol – 7.65×20mm Longue)
- Manufacture d'armes de Tulle
- submachine guns
- MAT-49 (France – submachine gun – 9×19mm Parabellum)
- Manufacture d'Armes des Pyrénées Françaises
- Pistols
- DES Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- DES-69 (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- DES-96 (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Mikros Pistol (French Republic – unknown date – semi-automatic pistol – .25 ACP)
- Model. Bcf 66 Pistol (French Republic – unknown date – semi-automatic pistol – .32 ACP, .380 ACP)
- Model. C Pistol (French Republic – unknown date – semi-automatic pistol – .32 ACP)
- Model. D Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. D2 Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. D3 Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. D4 Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. D6 Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. D8 Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. L Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle, .32 ACP, .380 ACP)
- Model. Ld (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. Le (French Republic – unknown date – semi-automatic pistol – .32 ACP)
- Model. Lf (French Republic – unknown date – semi-automatic pistol – .380 ACP)
- Model. R (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle, .32 ACP)
- Model. RD Pistol (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. RR 17 (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle, .32 ACP)
- Model. RR 51 (French Republic – unknown date – semi-automatic pistol – .32 ACP)
- Model. RR 59 (French Republic – unknown date – semi-automatic pistol – .32 ACP)
- Model. RANGER (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Model. 16 (French Republic – unknown date – semi-automatic pistol – .32 ACP)
- Model. 17 (French Republic – unknown date – semi-automatic pistol – .32 ACP)
- Model. 52 (French Republic – unknown date – semi-automatic pistol – .22 Long Rifle)
- Manurhin
- Pistols
- Manurhin P38 (Germany, France – semi-automatic pistol – 9×19mm Parabellum: Walther P38 Variant)
- Manurhin P1 (France – semi-automatic pistol – 7.65×21mm Parabellum, 9×19mm Parabellum, .22 Long Rifle)
- Manurhin PP (Germany, France – compact semi-automatic pistol – .22 Long Rifle, .25 ACP, .32 ACP, .380 ACP: Walther PP Variant)
- Manurhin PP Sport (France – compact semi-automatic pistol – .22 Long Rifle, .25 ACP, .32 ACP, .380 ACP)
- Manurhin PPK (France – subcompact semi-automatic pistol – .22 Long Rifle, .25 ACP, .32 ACP, .380 ACP)
- Revolvers
- Manurhin MR 73 (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Manurhin MR 32 (France – double-action revolver – .32 S&W Long)
- Manurhin MR 73 Gendarmerie (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Manurhin MR 73 Match (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Manurhin MR 73 Sport (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Manurhin MR 88 (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Manurhin MR 93 (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Manurhin MR 96 (France – double-action revolver – 9×19mm Parabellum, .22 Long Rifle, .357 Magnum .38 Special)
- Rifles
- Manurhin SG 540 (Switzerland, France – assault rifle – 5.56×45mm NATO: Licensed Production SIG SG 540)
- Manville gun
- Marek 3J (United Kingdom – submachine gun – .45 ACP)
- Marek Type S (United Kingdom – submachine gun – .45 ACP: single-barrel variant)
- Marek Type D (United Kingdom – submachine gun – .45 ACP: double-barrel variant)
- Marek Type T (United Kingdom – submachine gun – .45 ACP: triple-barrel variant)
- Marlin Firearms
- MASAF (Iran – assault rifle – 5.56×45mm NATO)
- Mateba Autorevolver (Italy – semi-automatic Revolver – Various)
- Mauser
- Machine Guns
- Mauser EW-141 (Nazi Germany – Vehicle-Mounted Machine Gun – 7.92×57mm)
- Pistols
- Mauser HSc (Germany – Compact semi-automatic pistol – .32ACP, .380 ACP)
- HSc Super (German – Compact semi-automatic pistol – .32ACP, .380 ACP)
- Mauser M1910 (German Empire – Subcompact semi-automatic pistol – .25 ACP)
- Mauser C96 (German Empire – semi-automatic pistol – 7.63×25mm Mauser)
- Mauser P04 Naval Luger (German Empire – semi-automatic pistol – 9×19mm Parabellum: P04 Luger Variant)
- Mauser WTP2 (Weimar Republic – Subcompact semi-automatic pistol – .25 ACP)
- Rifles
- Mauser Gewehr 98 (German Empire – bolt-action rifle – 7.92×57mm Mauser, 8×57mm IS)
- Mauser Karabiner 98a (German Empire – bolt-action carbine – 7.92×57mm Mauser, 8×57mm IS)
- Mauser Karabiner 98b (German Empire – bolt-action carbine – 7.92×57mm Mauser, 8×57mm IS)
- Mauser Gewehr 98 Sniper Conversion (German Empire – bolt-action sniper rifle – 7.92×57mm Mauser, 8×57mm IS)
- Mauser M 98 (Germany – bolt-action carbine – 7.92×57mm Mauser, 8×57mm IS, Many other commercial cartridges)
- Mauser M 98 Magnum (Germany – bolt-action carbine – .338 Lapua Magnum, .375 Holland & Holland, .416 Rigby, .450 Dakota, .458 Lott, .500 Jeffery)
- Mauser Model 1889 (German Empire – bolt-action rifle – 7.65×53mm Argentine)
- submachine guns
- Mauser MP-57 (West Germany – submachine gun – 9×19mm Parabellum)
- Maxim MG 08 (German Empire – Heavy Machine Gun – 8×57mm IS)
- Maxim IMG 08 (German Empire – Aircraft-Mounted Heavy Machine Gun – 8×57mm IS)
- Maxim MG 08/15 (German Empire – Medium Machine Gun – 8×57mm IS)
- Maxim MG 18 TuF (German Empire – Anti-Aircraft Gun – 13.2×92mmSR)
- Maxim 1910 (Russian Empire – Heavy Machine Gun – 7.62×54mmR)
- MC255 (US – Revolving Shotgun)
- MC255-12 (US – Revolving Shotgun – 12 gauge)
- MC255-20 (US – Revolving Shotgun – 20 gauge)
- McMillan Firearms Manufacturing LLC
- Rifles
- McMillan M87 (US – Bolt-Action Anti-Materiel Rifle – .50 BMG)
- McMillan M88 (US – Bolt-Action Anti-Materiel Rifle – .50 BMG)
- Tac-50 (US – Bolt-Action Anti-Materiel Rifle – .50 BMG)
- Tac-50 A1 (US – Bolt-Action Anti-Materiel Rifle – .50 BMG)
- Tac-50 A1-R2 (US – Bolt-Action Anti-Materiel Rifle – .50 BMG)
- Tubb-2000 (US – semi-automatic rifle – 6mm BR, 6mm XC, 7mm-08 Remington, .22–250 Remington, .308 Winchester)
- Tubb-2000 Spec-Tac-LR (US – semi-automatic rifle – 6mm BR, 6mm XC, 7mm-08 Remington, .22–250 Remington, .308 Winchester)
- Tubb-2000c (US – semi-automatic rifle – 6mm BR, 6mm XC, 7mm-08 Remington, .22–250 Remington, .308 Winchester)
- Tubb-2000t (US – semi-automatic rifle – 6mm BR, 6mm XC, 7mm-08 Remington, .22–250 Remington, .308 Winchester)
- McCrudden light machine rifle
- Mechanical and Chemical Industry Corporation
- Launchers
- GL-40 (Republic of Turkey/United States – unknown date – single-shot underslung grenade launcher – 40×46mm Grenade: Turkish variant of the American M203 grenade launcher.)
- T-40 (Grenade Launcher) (Republic of Turkey/United States – Mechanical and Chemical Industry Corporation/AAI Corporation – unknown date – single-shot underslung grenade launcher – 40×46mm Grenade: Turkish variant of the M203 grenade launcher.)
- Machine Guns
- MKEK MG-3 (Turkey – general-purpose machine gun – 7.62×51mm NATO)
- Rifles
- MKEK G3A7 (Turkey – battle rifle – 7.62×51mm NATO: G3A3 Variant)
- MKEK G3A7A1 (Turkey – battle rifle – 7.62×51mm NATO: G3A4 Variant)
- MKEK MPT (Turkey – Rifle)
- MKEK OPT-556 (Turkey – assault rifle – 5.56×45mm NATO)
- submachine guns
- MKEK SMP5 (Turkey, Germany – submachine gun – 9×19mm Parabellum: HK MP5 Variant)
- MKEK SMP5-K (Turkey, Germany – Compact submachine gun – 9×19mm Parabellum: HK MP5-K Variant)
- Mekanika
- Machine Guns
- Uirapuru (Federative Republic of Brazil – unknown date – general-purpose machine gun – 7.62×51mm NATO)
- submachine guns
- MEMS M-52/60 (Argentina – submachine gun – 9×19mm Parabellum)
- MEMS M-67 (Argentina – submachine gun – 9×19mm Parabellum)
- Mendoza
- Machine Guns
- Mendoza RM2 (Mexico – light machine gun – 7.92×57mm Mauser, .30-06)
- submachine guns
- Mendoza HM-3 (Mexico – submachine gun – 9×19mm Parabellum, .380 ACP)
- Mendoza HM-3S (Mexico – submachine gun – 9×19mm Parabellum, .380 ACP)
- Meriden Pocket Pistol (France – Break-Action Revolver – .32 S&W, .38 S&W)
- Mershon and Hollingsworth M1855 (US – automatic rifle – )
- Métral submachine gun (France – submachine gun – 9×19mm Parabellum)
- MG 14 (German Empire – general-purpose machine gun – 8×57mm IS)
- MG 14/17 (German Empire – general-purpose machine gun – 8×57mm IS)
- MG 14z (German Empire – general-purpose machine gun – 8×57mm IS)
- MGV 176 .22 (Slovenia – submachine gun – .22 Long Rifle)
- Micro Anthis (France – integrally suppressed Compact assault rifle – 5.56×45mm NATO)
- Milcam 5.56 mm rifle (UK – bolt-action rifle – 5.56×45mm NATO)
- Military Police Systems, Inc.
- Shotguns
- AA-12 (United States – Maxwell Atchisson, Military Police Systems, Inc. – 1972 (Original Variant), 1987–2005 (Military Police Systems, Inc.) – Fully Automatic Combat Shotgun – 12 gauge: Originally designed by Maxwell Atchisson, who sold the rights of the weapon to Military Police Systems, Inc. in 1987. Presented to the United States Marine Corps in 2004, but was never adopted.)
- AA-12 CQB (United States – Military Police Systems, Inc. – unknown date – Compact Fully Automatic Combat Shotgun – 12 gauge: Compact variant of the AA-12 with a shorter 13" barrel. Half a pound lighter than the original AA-12.)
- Milkor
- Launchers
- Milkor UBGL (South Africa – Underslung Grenade Launcher – 40mm)
- Milkor MGL (South Africa – Grenade Launcher – 40×46mm SR Grenade)
- Milkor Stopper (South Africa – single-shot grenade launcher)
- submachine guns
- Milkor BXP (South Africa – submachine gun – 9×19mm Parabellum)
- Milkor BXP Tressitu (South Africa – submachine gun – 9×19mm Parabellum)
- Minebea
- Ministry of Defence Industry of Azerbaijan
- Rifles
- Istiglal (Azerbaijan – semi-automatic anti-material rifle – 14.5×114mm)
- Mubariz (Azerbaijan – semi-automatic anti-material rifle – 12.7×108mm)
- Minuteman submachine gun (US – submachine gun – .45 ACP)
- Mitchell submachine gun (New Zealand – submachine gun – 9×19mm Parabellum: Prototype)
- Mk 12 Mod 0 (US – semi-automatic designated marksman rifle – 5.56×45mm NATO)
- Mk 12 Mod 1 (US – semi-automatic designated marksman rifle – 5.56×45mm NATO)
- Mk 13 Mod 0 (US – bolt-action rifle – .300 Winchester Magnum)
- Mk 13 Mod 1 (US – bolt-action rifle – .300 Winchester Magnum)
- Mk 13 Mod 2 (US – bolt-action rifle – .300 Winchester Magnum)
- Mk 13 Mod 3 (US – bolt-action rifle – .300 Winchester Magnum)
- Mk 13 Mod 4 (US – bolt-action rifle – .300 Winchester Magnum)
- Mk 13 Mod 5 (US – bolt-action rifle – .300 Winchester Magnum)
- Mk 15 Mod 0 (US – Bolt Action Anti-Materiel Rifle – .50 BMG: McMillian M88 PIP Variant)
- Mk 18 Mod 0 Grenade Launcher (US – grenade machine gun – 40×46mm SR Grenade)
- Mk 19 Mod 0 (US – grenade machine gun – 40×53mm Grenade)
- Mk 19 Mod 1 (US – grenade machine gun – 40×53mm Grenade)
- Mk 19 Mod 2 (US – grenade machine gun – 40×53mm Grenade)
- Mk 19 Mod 3 (US – grenade machine gun – 40×53mm Grenade)
- Mk 19A (US – grenade machine gun – 40×53mm Grenade)
- Mk 20 Mod 0 (US – grenade machine gun – 40×46mm SR Grenade)
- Mk 23 Mod 0 (US – light machine gun – 5.56×45mm NATO: Stoner 63A1 Commando Variant)
- Mk 23 Mod 0 (Germany – semi-automatic pistol – .45 ACP: HK Mark 23 Variant)
- Mk 24 Mod 0 (Switzerland, Germany – semi-automatic pistol – 9×19mm Parabellum: SIG Sauer P226 Variant)
- Mk 24 Mod 0 (US – submachine gun – 9×19mm Parabellum: S&W Model 76 Variant)
- Mk 43 Mod 0 (US – light machine gun – 7.62×51mm NATO: M60E4 Variant)
- Mk 46 Mod 0 (US – light machine gun – 5.56×45mm NATO: M249 Variant)
- Mod. 1918 S.I.A. light machine gun (Italy – light machine gun – 6.5×52mm: Browning M1918 BAR Variant)
- Model 45A (US, Philippines – battle rifle – .30-06)
- Model T Machine Gun (US – light machine gun – .22 Long Rifle: Prototype)
- Morgan Arms
- MORS submachine gun (Poland – submachine gun – 9×19mm Parabellum)
- Mosin–Nagant (Russian Empire – bolt-action rifle – 7.62×54mmR)
- Dragoon Rifle (Soviet Union – bolt-action rifle – 7.62×54mmR)
- Mosin–Nagant M/28 (Russian Empire, Finland – bolt-action rifle – 7.62×54mmR)
- Mosin–Nagant M38 (Soviet Union – bolt-action carbine – 7.62×54mmR)
- Mosin–Nagant M91 (Russian Empire – bolt-action rifle – 7.62×54mmR)
- Mosin–Nagant M1907 carbine (Russian Empire – bolt-action carbine – 7.62×54mmR)
- Mosin–Nagant M1916 (Russian Empire, US – bolt-action rifle – 7.62×54mmR)
- Obrez (Russian Empire – sawed-off bolt-action rifle – 7.62×54mmR)
- OTs-48 (Russian Federation – bolt-action sniper rifle – 7.62×54mmR)
- OTs-48K (Russian Federation – shortened bolt-action sniper rifle – 7.62×54mmR)
- Mossberg
- MP 35 (Nazi Germany – submachine gun – 9×19mm Parabellum)
- MPA submachine gun (Argentina – submachine gun – 9×19mm Parabellum)
- MSSR (Philippines – semi-automatic sniper rifle – 5.56×45mm NATO)
- MSSR NFWS (Philippines – integrally suppressed semi-automatic sniper rifle – 5.56×45mm NATO)
- Muharram machine gun (Iran – Gatling machine gun – .50 BMG)
- Mukden Arsenal Type II (China – submachine gun – .45 ACP)
- Murata rifle (Japan – bolt-action rifle – 11×60mmR Murata)
- MZ14 (US – assault rifle – 5.56×45mm NATO)
Firearms are cited from: https://modern-firearms-fo4.info/informations/full-weapon-list/
- List of firearms by era
- List of firearms by country
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- List of firearm cartridges
- List of semi-automatic firearms