Munitions

40x46 mm low-velocity grenade

Also known as
  • 40x46 mm LV
  • 40 x 46 mm
  • 40x46mm LV
  • 40 x 46 mm LV
  • 40 mm LV
  • 40 mm low-velocity grenade
  • 40mm LV grenade
  • M433 HEDP
  • M781 TP

The 40x46 mm low-velocity grenade is the handheld grenade-launcher cartridge family used by M79-, M203-, M320-, and similar 40 mm LV launchers. The family spans tactical, training, smoke, illumination, irritant, sound-and-flash, and other special-purpose cartridges; this relationship-only page documents that ammunition context without assigning independent conflict use to the cartridge family.

40x46 mm low-velocity grenade, 40 mm low-velocity grenade-launcher cartridge, Munitions
Image source: M433 HEDP cutaway.png
Profile / Specs

Specifications

Caliber
40x46 mm
Velocity class
Low velocity
Compatible launchers
Standard 40 mm LV grenade launchers and rifle attachments, including M79, M203, and M320 examples in manufacturer sources
Common roles
High explosive, practice, illumination, smoke or obscurant, sound and flash, irritant, and other special-purpose cartridges
Representative cartridge length
C.I.P. lists a 110 mm maximum cartridge length for 40 x 46.
Representative tactical round
M433 HEDP uses a 40x46 mm M118 cartridge case; AMTEC lists 76 m/s muzzle velocity, 400 m maximum range, and 63 mm steel penetration.
Representative training round
M781 uses a 40x46 mm M212 cartridge case; AMTEC lists 76 m/s muzzle velocity and 400 m maximum range.
Variants

The 40x46 mm low-velocity family is a cartridge class rather than a single projectile; designation rows below identify representative tactical and training rounds documented by official or manufacturer sources.

VariantConfigurationDesignation notes
M433 HEDPTactical high-explosive dual-purpose cartridge

U.S. Army and AMTEC material identify M433 as the primary 40 mm LV tactical HEDP round for handheld launchers such as the M203 and M320, with a 40x46 mm M118 case and a 400 m maximum range.

Sources: USAASC 40 mm grenades, AMTEC M433 HEDP sheet

M781 TPLow-velocity practice cartridge

U.S. Army, AMTEC, and UDC sources describe M781 as the main 40 mm LV training or practice cartridge, using an M212 case and an orange signal-dye projectile to train for the M433 trajectory.

Sources: USAASC 40 mm grenades, AMTEC M781 practice sheet, UDC M781 chalk round

M433E1 HEDPModernized low-velocity HEDP cartridge

USAASC describes M433E1 as a modernized 40 mm low-velocity HEDP point-detonating cartridge for M320 launchers and legacy M203 launchers.

Sources: USAASC Smarter Resupply

40 mm LV smoke, illumination, sound-and-flash, and irritant cartridgesSpecial-purpose cartridge roles

Rheinmetall describes standard 40 mm LV cartridges across practice, impulse or less-lethal, sound-and-flash, irritant, high-explosive, illumination, and smoke or obscurant roles.

Sources: Rheinmetall 40-mm ammunition and launchers

Firing Weapons

The ammunition family is tied to handheld 40 mm low-velocity launchers; catalog links are limited here to launcher pages already present in the public catalog.

Firing weaponWeapon typeFiring evidence
M203 40 mm grenade launcher, Under-barrel grenade launcher, Infantry WeaponsM203 40 mm grenade launcherUnder-barrel grenade launcher

Hellenic Defense Systems lists the 40x46 mm LV grenade for the M203, while AMTEC and UDC product material identify M433 or M781 40x46 mm low-velocity cartridges with M203 use.

Sources: Grenade 40mmX46mm Low Velocity, AMTEC M433 HEDP sheet, UDC M781 chalk round

Arcus 40 UBGL, 40x46 mm under-barrel grenade launcher, Infantry WeaponsArcus 40 UBGLUnder-barrel grenade launcher

Arcus describes the Arcus 40 UBGL as a 40x46 mm under-barrel grenade launcher using M406-type low-velocity grenades.

Sources: Arcus 40 UBGL 40 x 46 mm Underbarrel Grenade Launcher

RBG-6, 40x46 mm six-shot revolving grenade launcher, Infantry WeaponsRBG-6Revolving grenade launcher

M Adler D and Agencija Alan product sources describe the RBG-6 as a shoulder-fired six-shot launcher chambered for 40x46 mm low-velocity grenades.

Sources: M Adler D Product Data, Agencija Alan RBG-6 Product Page

Why some launchers are not linked

Sources also name M79 and M320 launchers, but this record only links launcher records already present in the public catalog; those unlinked launchers remain compatibility context rather than new placeholder pages.

Sources: Grenade 40mmX46mm Low Velocity, AMTEC M433 HEDP sheet

Cartridge Family Context

The low-velocity designation separates handheld-launcher ammunition from high-velocity 40 mm rounds for automatic grenade launchers. Sources describe 40x46 mm LV cartridges as a broad family rather than one uniform payload, with tactical, training, illumination, smoke, irritant, sound-and-flash, and other mission-specific loads.

Tactical baseline

U.S. Army acquisition reporting names M433 HEDP as the primary 40 mm LV tactical round for M203 and M320 launchers.

Training baseline

The same Army reporting identifies M781 TP as the primary 40 mm LV training round, while manufacturer sheets describe its signal-dye practice function.

Launcher boundary

Rheinmetall and Hellenic Defense Systems describe standard 40 mm LV compatibility with handheld launchers and rifle attachments, not 40x53 mm automatic-grenade-launcher ammunition.

Timeline

40x46 mm low-velocity grenade Key Events

  1. U.S. Army 40 mm modernization effort

    USAASC reported that the Army began a modernization push in 2009 to improve training realism, lethality, and new capabilities across the 40 mm grenade family.

    Sources: USAASC 40 mm grenades

  2. Low-velocity day-night training round milestone

    USAASC identified the M781E1 low-velocity TP-DNT effort as a day-night-thermal training round program that had reached milestone C in 2017.

    Sources: USAASC 40 mm grenades

  3. M433E1 modernization described

    USAASC described the M433E1 as a modernized 40 mm low-velocity HEDP cartridge intended for the M320 and legacy M203 launcher families.

    Sources: USAASC Smarter Resupply

Media

40x46 mm low-velocity grenade Images

40x46 mm low-velocity grenade, 40 mm low-velocity grenade-launcher cartridge, Munitions - view 1
Source: Marine Air Support Squadron 2 Machine Gun Shoot 140812-M-UR592-328.jpg
40x46 mm low-velocity grenade, 40 mm low-velocity grenade-launcher cartridge, Munitions - view 2
Source: M433E1-Exterior-Edited-Courtesy-of-AMTEC-and-PM-MAS.png
Related Weapon Systems
RBG-6, 40x46 mm six-shot revolving grenade launcher, Infantry WeaponsInfantry WeaponsRBG-640x46 mm six-shot revolving grenade launcherThe RBG-6 is a Croatian 40x46 mm shoulder-fired revolving grenade launcher from M Adler D, built around a semi-automatic gas-operated action, a six-round cylinder, and low-velocity grenade ammunition for infantry fire support. Direct Syria reporting documented RBG-6 launchers among opposition weapons flows, while official Croatian export and manufacturer pages describe the weapon's squad-firepower role, sighting arrangement, barrel versions, and ammunition family.
Cartridge, 105 mm, Illuminating, M314, 105 mm howitzer-fired illuminating cartridge with parachute-retarded canister, MunitionsMunitionsCartridge, 105 mm, Illuminating, M314105 mm howitzer-fired illuminating cartridge with parachute-retarded canisterThe M314 is a U.S. 105 mm howitzer illumination cartridge family that ejects a flare canister under parachute for battlefield lighting. Army ammunition manuals list earlier M314-series rounds for M101/M102-era howitzers, while Army portfolio material identifies the M314A3 visible-light round as a 105 mm M119-series illumination cartridge with a semi-fixed case, time fuze, expelling charge, illuminant canister, and parachute assembly.

Sources

C.I.P. 40 x 46Publisher: Commission Internationale Permanente | Note: Supports the 40 x 46 cartridge designation, U.S. country-of-origin note, and representative C.I.P. dimensional context. | Accessed: 2026-07-13Rheinmetall 40-mm ammunition and launchersPublisher: Rheinmetall | Note: Supports the low-velocity 40 mm ammunition class, examples of cartridge roles, and compatibility with standard 40 mm LV grenade launchers or rifle attachments. | Accessed: 2026-07-13Grenade 40mmX46mm Low VelocityPublisher: Hellenic Defense Systems | Note: Supports 40x46 mm low-velocity grenade nomenclature and handheld launcher compatibility examples including the M79, M203, and M320. | Accessed: 2026-07-13USAASC 40 mm grenadesPublisher: U.S. Army Acquisition Support Center | Note: Supports U.S. Army low-velocity 40 mm family context, M203 and M320 launcher association, M433 and M781 baseline roles, and 2009/2017 modernization timeline context. | Accessed: 2026-07-13USAASC Smarter ResupplyPublisher: U.S. Army Acquisition Support Center | Note: Supports M433E1 modernization context and its M320 or legacy M203 launcher association. | Accessed: 2026-07-13AMTEC M433 HEDP sheetPublisher: AMTEC Corporation / National Defense Corporation | Note: Supports M433 HEDP components, 40x46 mm M118 cartridge case, M203 and M320 launcher association, maximum range, muzzle velocity, and representative penetration figure. | Accessed: 2026-07-13AMTEC M781 practice sheetPublisher: AMTEC Corporation / National Defense Corporation | Note: Supports M781 practice cartridge components, 40x46 mm M212 case, maximum range, muzzle velocity, and AMTEC production context. | Accessed: 2026-07-13UDC M781 chalk roundPublisher: Ultra Defense Corp | Note: Supports M781 low-velocity practice cartridge role, M203 and M79 launcher association, M212 case construction, signal-dye function, and ballistic-match context for M433 training. | Accessed: 2026-07-13Arcus 40 UBGL 40 x 46 mm Underbarrel Grenade LauncherPublisher: Arcus JSC | Note: Supports Arcus 40 UBGL relationship to 40x46 mm low-velocity M406-type grenade ammunition. | Accessed: 2026-07-13M Adler D Product DataPublisher: M Adler D | Note: Supports RBG-6 relationship to 40x46 mm low-velocity ammunition and technical compatibility context. | Accessed: 2026-07-13Agencija Alan RBG-6 Product PagePublisher: Agencija Alan | Note: Supports RBG-6 relationship to 40x46 mm low-velocity ammunition and listed ammunition types. | Accessed: 2026-07-13M433 HEDP cutaway.pngPublisher: Wikimedia Commons | Note: Supports image provenance for a public-domain U.S. Army cutaway image in the 40x46 mm grenade category. | Accessed: 2026-07-13Marine Air Support Squadron 2 Machine Gun Shoot 140812-M-UR592-328.jpgPublisher: Wikimedia Commons | Note: Supports image provenance for a public-domain U.S. Marine Corps photo showing M781 practice rounds and M433 HEDP rounds at Camp Hansen. | Accessed: 2026-07-13M433E1-Exterior-Edited-Courtesy-of-AMTEC-and-PM-MAS.pngPublisher: Wikimedia Commons | Note: Supports image provenance for a public-domain M433E1 exterior image sourced to AMTEC and PM MAS. | Accessed: 2026-07-13