So, what *was* that gun crew doing?

Hmmmmm.  There's this pic from a post



 

Field artillerymen of Battery A, 2-218th Field Artillery, 41st Infantry Brigade Combat Team, Oregon Army National Guard, fire a 105mm shell from a howitzer at Yakima Training Grounds, Wash., during the unit's annual training Aug. 9. Photo by Sgt. Chad Layton of Battery A, 2-218th Field Artillery, Oregon Army National Guard.
 

Okay - I first brought up this pic in this post ten days ago.  It's a pretty picture, and does show how a muzzle brake works to reduce recoil - but to this artilleryman's eyes there were just too many things wrong with it.  But, as I said, I never served the light guns during my career, except in the very first months of it, when I was in the Officer's Basic Course.  And I was never manning the guns during the night portions of our training, I was either a Forward Observer or a Fire Direction Officer at night during what was termed the "3 day war" capstone exercise.  Heh.  We were still living under the Carter budget at that time.  Not too long later that exercise went to 6 or 7 days.  That sort of thing is expensive, it's one of the first things cut back when money tightens up.  But I'll back out of that rathole and back over into the original one.   Who knew rats went condo?

Okay - we see the pretty streaks of light.  Something else we don't see however is the crew.  And the guy firing the gun is doing so from what is to me the wrong side of the gun - though perhaps that gun is fired from the left side - like I said, I never served on these.  But I suspect it's because he wants to be where he won't be in the sparkly-spaces...  and the rest of the crew didn't want to be, either.  Burning powder particles probably damage your clothing and do rude things to exposed skin.

I think this crew was having fun - if possibly dangerous fun.  They may have taken all needful precautions - I dunno, but I don't mind bringing it up - they got the pic published on www.army.mil, 

For examples of what I mean, check out the following pictures, such as  this one.  And, this.  Now, this.   Not to mention this.  And even this, from Russia's invasion of South Ossetia.  Or this close-up of the muzzle of a naval 5-inch gun.

And for those of you too lazy to click links - here:



So, what don't we see - in the day or night shots?  Old or modern cannon?  With muzzle brakes or without? Those cute sparkly things - which I don't think are an artifact of good camera work.  Well, they are, but not in a creative sense.  I think they're burning powder grains.  And I think they're burning that way because they're wet.  It could be they stuck something else in the bore (even worse idea, actually) to achieve that effect - but I bet those guys shot wet powder - and knew they were doing it, because the crew isn't in the shot.  And if these guys are old school, I have my suspicions as to how they got wet, too.  The absence of the crew leads me to believe they were doing this deliberately for the shot.

And they pretty much had to be shooting a projectile, too... because the semi-fixed ammunition fired by 105mm guns comes as a unit, powder and projectile.  Meaning you can't just load the casing and powder and shoot it - unless you're prepared to explain why you've got a round left over.  And if that's true - well, that round fell short, because the powder burn is incomplete.    Lots of factors to account for there - none of which I have knowledge of - I just know that if I was the OIC of that position, and I walked up on that - the crew would be getting one hell of a hairy eyeball.

Yeah, I was that kind of officer.  No fun.

Remember the tease I posted earlier this week?  That was a 105mm powder grain, looking end on.  The holes in it are to provide more surface area for combustion, to better ensure the grain burns completely in the barrel.  Artillery, depending on the range you're shooting and whether or not you are shooting high angle, uses different shapes of propellant grain so that you can achieve a range of different bore pressures so that you have flexibility about how and where you get your projectile to the target by varying the quadrant elevation of the piece.  Direct fire weapons also use powders shaped to the purpose, but they are generally slightly overloaded, to ensure the projectile is at max velocity for the projectile type and barrel length even if there are variations of local conditions of temperature and humidity.  Hence, there's always a lot of flash when they fire, from unburned powder.  

This occurs with artillery, too, especially firing large charges - but lots of flash is usually not a good thing when firing artillery - it generally means your round is going to do what CAPT H and Murray pretty much accuse *all* of our rounds of doing - fall short.  (Just a good reason to not be along the gun-target line then, boyos.)  But one thing you don't get is burning particles like those in the picture - even the bags the powder is contained in are consumed when the powder burns - it does burn, technically, not detonate.  It just burns very fast (hence the holes). 

Here's an example of the 105mm powder grain from the tease (on the right) and a 8in cannon powder grain in the left side of the picture:


 
Quite a difference in size even if you don't yet have a scale comparison. 

So, lets give you a size comparison:



That's a 16in Navy, 175mm, 203mm,  two different sizes of 105mm powder grains, and a long rod 155mm running underneath, with a 7.62 Tokarev pistol cartridge for comparison.  Even that tiny grain on the right has a hole down the middle of it, as does that rod of 155mm powder.  There are thousands of these in the powder bags, and several different powder bags, called "charges".

Such as those seen here, 16inch charges being loaded into (I believe) the guns of the USS Iowa.

Anyway - that's what truly caught my eye about the picture, and would have really caught my attention were I the OIC of that gun position.  Fun, yes, and boys will be boys - but dangerous, too.

But it gave me an excuse to write that artillery propellant post, too.