Thread by @noclador

The L119 and M119 howitzers donated to Ukraine - how do they work?

An artillery thread with too many videos 🧵:

In this video a Ukrainian gun crew is firing M1 HE projectiles with M739A1 point detonating fuzes at increment 7.
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If the terms in the first tweet confused you, then please read my linked M777 howitzer thread below, in which I explain the four components needed to fire a round:

• projectile
• fuze
• charge
• primer

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Before you can fire the gun it must be emplaced. This means turning the L119/M119's barrel 180° degrees, which requires to unscrew one wheel. The gun is then secured onto a round firing platform for improved stability.

(No worries: the wheel takes just 15 seconds to unscrew)
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Now gun section chief and gunner sight the gun, while the rest of the crew prepare the ammunition.
Unlike 155mm ammo which is moved on pallets, 105mm ammo still comes in wooden crates, which contain two cardboard tubes.
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Wooden crates, cardboard tubes - sounds ancient & it is. This ammo was developed in the 1930s for the M2A1 howitzer, which was extensively used in WWII.

Here is a photo of a US Marines on Iwo Jima with the same wooden crates & cardboard tubes Ukrainian crews handle in 2022.
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From Normandy to Vietnam - the M1 High Explosive projectile, the M14 Cartridge Case, the M67 Propelling Charges and the M28 Percussion Primer were a mainstay of US Army and US Marine Corps artillery units.
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From 1964 on the M2A1 (later renamed M101) was replaced by the lighter M102.
In the late 1980s the US Army looked for a replacement for the M102, which was able to fire the semi-fixed 105mm M1 ammo family of the M101/M102.

Photo: 82nd Airborne Division M102 crew in Grenada.
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Ultimately the US Army settled on a US produced variant of the British L119, which itself is a variant of the British Army's L118, which uses (in typical British fashion) a unique 105mm ammo.

The unique ammo is the reason the UK bought Australian L119 for Ukraine, because
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there isn't enough L118 ammo, while there are millions of M1 rounds stored all over the world. More about the L118's ammo at the end of this thread.

Now that we know the history of the M119 and L119, and their ammo, let's have a look what is inside the cardboard tubes.
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Each tube contains actually just two things:

• the projectile
• the M14 cartridge case

The M14 cartridge case (made from brass or steel) contains a M28 percussion primer assembly and a M67 propelling charge, which consists of seven individually numbered propellant bags.
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The seven bags are tied together, in numerical order, with acrylic cord and assembled around the central primer flash tube: Increment 1 at the base and Increment 7 toward the mouth of the cartridge case.

The M28 primer assembly consists of a black powder filled perforated
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primer flash tube, which is attached to a M61 percussion primer at the cartridge's bottom.

To fire a round the M119's firing pin strikes the M61 primer, which then ignites the black powder in the primer flash tube, which in turn initiates the propelling charges, which then
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propel the projectile out of the barrel and towards the enemy.

The more charge bags you leave in the cartridge, the further the projectile will fly.

The M1 family consists of nine projectiles, which all use the M14 cartridge and the M67 propelling charge. Over time the
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US Army introduced new projectiles with improved range, which use new propellant charges (i.e. the M913 uses a single M229 charge bag). But all of them use the M28 percussion primer and M14 cartridge case.

As Ukraine won't receive the new projectiles I will skip them.
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Now let's look at the projectile.

A projectile will not detonate without a fuze. Fuzes come in separate metal boxes and depending on mission and type of projectile different fuzes are used: here M739A1 point detonating fuzes are mounted on M1 High Explosive projectiles.
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Current M1 family projectiles are (incl. their max. range):

• M1 High Explosive (HE), 11.5km
• M60A2 White Phosphorus smoke, 15.1km
• M84A1 Hexachloroethane smoke, 11.5km
• M314A3 Visible Light illuminating, 19.5km
• M927 HE Rocket Assisted, 16.5km

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• M1064 Infrared illuminating, 19.5km
• M1130 HE Base Bleed, 13km

Point detonating (PD), time, proximity & multi-option fuzes exist, but i.e. only time fuzes work on illuminating projectiles.

So far we have only seen M1 & M927 projectiles with M739A1 PD fuzes in Ukraine.
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Now that the gun is set up and the fuzes are screwed in, it is time to make some noise.

The projectile is mounted onto the cartridge. If the projectile is not fired at maximum range the unneeded charge bags are left dangling from their acrylic cord outside the cartridge.
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The reason being that the section chief can thus control that the projectile is fired with the correct amount of propellant.

In this video @173rdAbnBde gunners fire M84 HC smoke with M762 electronic time fuzes (set by hand) at charge 5. Therefore the section chief rips
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charge bags 6 and 7 away before the projectile is loaded into the gun.

Once the gun is loaded, the breech is closed and the gunner pulls the firing lever. After firing the breech is opened, the now empty cartridge is tossed aside, and the barrel checked before the next round
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is loaded.

Well trained US Army gun crews can fire a round every 6-7 seconds... if they prepared enough ammo in advance.
This gun crew at Fort Sill sends 10 rounds a minute downrange.

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Ukrainian L119 & M119 crews will achieve similar levels of speed (if given enough ammo).

Unlike L118 crews, who are slowed down by the unique British propellant cartridge, which is more complicated to check and load, and the need to ram the projectile into the barrel.
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Both - the Australian L119 and the American M119 - which Ukraine received are excellent guns, even though they were delivered without the digital fire control system, GPS sensor, inertial navigation system, and fire control computer the US Army's newest M119 variant has.
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At the end of this thread I want to thank the media team of the @173rdAbnBde: 90% of all existing M119 videos were made by them.

And I suggest everyone follow @denintern, a Ukrainian gun section chief, who is right now bonking russians in Kherson with an Australian L119.
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