Why train one's gun before loading?

it's one thing i always wondered. isn't it better to load before training? at college ROTC, we were prevented from touching any part of the '105 while the gunner and assistant gunner were setting trajectory. the reason was even a slight movement will throw the aim off. but i'm pretty sure loading a live round after this would create a bigger deviation, no matter how infinitessimal. also, it gives a moving target more lead in leaving one's aiming area. this, even during line-of-sight shooting, like in the case of an '88 anti-tank gun.

so why?

 

It might be that if multiple round types are available waiting to the last minute preserves some flexability. I'm pretty sure naval guns were loaded while being trained in azimuth, the bigger ones in some cases had to be at certain angles in elevation to be loaded so they were trained in elevation after loading. Back to land guns it is likely that they just didn't want people to be trying to load and train at the same time so the choice on which to do first may have been arbitrary. Keeping the gun unloaded to the last minute may have been considered slightly safer though.

 

My impression is that for naval pieces once you got over 5" or so returning to a fixed (or very limited range of elevations) was pretty much the standard. I also seem to recall some exceptions to this though. The late war automatic 6" and 8" guns in particular.

 

When you get to the point you need to power ram the projectile and powder, you need to come back to a specific loading elevation. The 105mm howitzer uses semi-fixed ammo so can be loaded from any elevation. It's been a long time, but when I went through the Ft. Sill artillery school I can't recall any such instruction. I do remember banging off a lot of rounds while the trainer and pointer kept the howitzer correctly pointed. I would think that by not loading the gun until it's on the correct direction and quadrant and keeping the breech open would allow the chamber and barrel to cool and thus limit the barrel wear.

 

As a basic answer to why "land" artillery is loaded at the last minute...Safety. You dont want to swing a loaded cannon around...you point at what you want dead, then load.

 

That was my first thought CAC, but I don't know how "correct" it is. Not pointing a loaded gun at something unless you want it dead is standard practice for us civilians but I don't know if it applies to field artillery too.

 

And when you move a loaded gun around...you point it to the earth...just in case.
Swivelling a cannon, you cant point it at the ground (pointing in the air is worse!) ANY stray arty round is stupidly dangerous....much more dangerous than a stray bullet. - Especially if there are friendlies near the target...Thats all i can think of.

 

In a training situation there is always a safety officer around to make sure the piece is pointed safely (clearing hill tops, not over-firing the impact area, etc.). As for being able to "swing a loaded cannon around", all I can say is-try it. These cannon weigh from several to many tons. You don't casually "swing them around"!

 

ok...the word was swivell...not swing. Ever heard of a swivell cannon?
And if you've ever seen a battery stop..set up...fire...pack back up and hop it out of the area before counter battery fire...you will see men pushing that bugger around quick smart...might even call it a "swing". They have to unhitch the gun and "swivell" it around...and again to re-attach to the carrier. You blokes use too many SPAs... : )

 

Have done all that back in the day. The battery is brought into position with the cannon unloaded. Then the guns are set parallel on an azmuth using the M-2 aiming circle while the ammo boys set out the ammunition. Only when that is done and a fire mission called and the firing data sent to the guns are they loaded. After the mission is over and the guns unloaded are they allowed to be moved. When I was in the army nothing was done re. firing without a safety officer. Even then mistakes happen. I was at Ft. Benning on an MG night shoot when somebody in a heavy arty battery mis-aligned a cannon and a fist-sized piece of shell fragment came within less than a foot of me! But that's ok, after all it was friendly fire.

 

Shite! You hear about unauthorised discharges with assault rifles...but a gun!? Would hate to be a safety officer...responsibility was never a strong point of mine...

 

In one sense it does not really matter whether the gun is loaded then laid (Trained) or vice versa. It can depend on the drills for the artillery piece. Some guns could only be loaded at a certain elevation, in which case they needed to be loaded then laid. Even if the gun has laid then loaded, the Layer (Trainer in the US?) has a duty to check that the gun is still layed correctly on the aiming point before firing each round. . It is possible for the lay to be disturbed by the act of loading or the recoil of the gun. . Guns should be brought into action on a firm level platform, but in some places it is not possible. In the Falklands War the 105mm Light Guns might move several inches with every round and after a fire mission the gun pushed forwards. .

In wartime in WW2, field artillery pieces were often kept loaded and layed on the SOS/ FPF target. The first rounds in response to the SOS could be fired by the gun sentries even when the rest of the gun detachments were at Rest. The guns were often already loaded when a new fire mission was ordered. This might mean emptying guns ona safe target if the mission called for a different ammunition nature or fuse setting.

As harolds points out in post #11 in peacetime (and lower intensity conflicts than WW2 ) guns are not loaded until a fire mission is ordered. Ending a fire mission with loaded guns might mean wasting expensive training ammunition or wasting time unloading guns with ejectors projectile.- a long long stick with a cup on the end to protect the fuse. (In WW2 there were occasional problems. One of the artillery regiments supporting the assault on Italy across the straits of Messina in Sep 1943 ended the night fireplan with loaded guns and hot barrels. There was no safe target on land or sea and it was judged unsafe to try to eject hot ammunition. Several 25 pdr guns were lost as the rounds cooked off)

With an anti tank shoot the orders are not "Fire Mission" but "Tank Alert" and the guns are not ordered to "Fire" but "Engage." When ordered to "Engage" the decision to fire the piece is delegated to the Layer, who has the authority to fire as soon as he his given the signal, (a slap on the back) that the gun is loaded and the loader is out of the path of the recoil. The No 1 will order corrections based on the fall of shot and the layer will train the piece on the target continuously in the case of a moving target. This is comparable to the example of the 88mm gun in the anti tank role.

I hope this helps!

 

Thank you Sheldrake! I should have pointed out earlier that after the ammunition is loaded into the gun then the layer and the pointer shout (I forget what) when their sights line up. When both are yelling they're on then the NCO in charge of the gun yells "fire" and another soldier pulls the lanyard.

 

How many rounds per minute?

 

Pulling out all the stops, I'd say for the 105mm, perhaps 12-13. For the 8" howitzer we could do 5 0r 6-but not for very long. Those bigger pieces heat up and that leads to trouble!

 

Depends on the type of gun and crew. A well trained crew is a pleasure to watch. I've posted this video before, but here it is again because it seems appropriate to this thread. This particular gun is an M-198 towed 155mm gun. Note that the deflection is verified and called out before each shot. Note also that the crew members on the left and right are adjusting deflection and quadrant (elevation) with each shot.

https://youtu.be/Aj5j9QUpuvo

Deflection is the variance from the Azimuth of Fire to which the artillery piece was originally laid, both stated in mils, a more precise measurement than degrees of azimuth on a compass. 360 degrees to a compass. 6400 mils=360 degrees so there are like 17.7777 mils to one degree. Traverse is the movement of the tube to the deflection, without repositioning the piece. Shift, is moving the entire gun, as in to a new position or to a deflection outside the traverse limits of the gun tube.

 

Is it wrong to be slightly turned on by that? : )

 

Ah yes, "deflection"! That was the term I was trying to remember (it's been a long time). Thanks USMCPrice.

 

"Battery adjust! Aiming point: this instrument!"