It’s gonna be a good day, ‘Tater

RODRIGUEZ LIVE FIRE COMPLEX, 41, SOUTH KOREA
08.07.2020
Video by Staff Sgt. Simon McTizic
2nd Brigade Combat Team, 1st Infantry Division Public Affairs
Soldiers from the 1-7 Field Artillery, 2nd Armored Brigade Combat Team, 1st Infantry Division show their Readiness and ability to Fight Tonight during their AT12 training at the Rodriguez Live Fire Complex, Republic of Korea.

https://www.dvidshub.net/991059d8-6551-4266-8b00-ab2b4a17bc18

Backyard Mortarmen, er, persons, um, perxns

Yes, there will eventually be video. The weather is not cooperating right now, anyway.

Data plate for the Subcaliber Mortar Device 3-F-8. Made by the US Navy for the Army National Guard. Prolly because the Regulars were happy with their larger, more expensive ones that required ranges.
The kit and the kaboodle to carry it in. Formerly owned by Charlie Company, 2nd Battalion, 108th Infantry of the New York ARNG. They still exist, though currently only as a “detachment” according to the battalion website.
The top tray, with 20 projectiles and the barrel.
Underneath the tray, with the tech manual, barrel adaptors (60mm, 81mm, and 107mm) as well as sundry circlips, o-rings, cleaning tools and three spare projos and spare parts. And two boxes of propellants.
Barrel assembled with the bottom plate (on the right) which sits down in the barrel and assures the tube is parallel to the mortar tube, and the top plate, on the left which keeps it all from dropping down the tube and keeps the muzzle accessible. On the 81s and 107s it would be a real PITA to drop the tube down the mortar.
Projectile prepared for loading. Spotting round in the nose, propellant in the tail. Interestingly, unlike the actual mortars, this is in fact a spigot mortar. There is a rod in the base of the barrel that enters the tailpiece when the mortarman drops the round. That lights off the blank, with the tailpiece actually functioning as a barrel. This let them use lighter charges. Because, as I mentioned in an earlier post – this was designed to be used *indoors* at local armories, often located downtown. The Guard could train at home station, in comfort, and not have to motor out somewhere and endure crappy weather, either. Not so dumb after all, eh?
Mounted in the mortar, ready to hang and drop, allowing the crew to go through all the drill and have some fun doing it. No, there’re no blanks in that round. There’s indoors in armories, then there’s indoors in the Armory. Our ceilings are rather much too low, thenkewverramuch.

Things that make ya go, hmmm.

 

So, we have a “Subcaliber Mortar Trainer Device 3-F-8.” Designed by the Navy for the ARNG, to be able to train with mortars at home station.

As I recently found a reliable source for the .22 caliber blanks it uses, well, we can shoot mortars now. Safely. It came with the tech manual, but no firing tables, so, I went looking. I found a ARNG training note in Google Books that addresses that issue, and I will follow that because, well, to generate firing tables, I hafta go all ARDEC on it and shoot the thing a fair bit to generate the necessary range and ordinate data. Whee! Gunnery nerds unite!

Below is a somewhat edited version of the blurb in the note. Nota Bene item “C.”

“7 . PROCEDURES FOR THE PREPARATION OF FIRING TABLES FOR DEVICE 3 – F – 8 SUB -CALIBER MORTAR TRAINER (ARMY Reference : Operation and Maintenance Guide for Device 3 – F – 8 NAV EXOS P1185 )

a. These instructions describe a method of preparing a usable, although not exact, firing table for Device 3 – F – 8 , Sub – Caliber Mortar Trainer , Using these procedures , the following firing table data can be obtained for each charge : Range Elevation Elevation change for 20 ft . Range Change, Probable Error Range Deflection, Maximum Ordinate.

b. Procedures : [Elided because it’s boring gunnery stuff no one but me cares about]

c. Care must be taken that the ordinate resulting from the charge and angle of elevation is not greater than the ceiling of the armory. [Emphasis added]”

These projectiles are steel, have some heft, and, when impacting, fire off a black powder blank. There is no discussion anywhere on what sort of surface you are shooting *at*.

Therein might be why these things are always in such good shape when you run across them. 1SG wasn’t letting anyone shoot steel projos on his wood floor of the basketball court, and the mortar platoon sergeant wasn’t going to ding up the inspectable item by shooting them at concrete…