Dispersion and the Big Guns

[CavemanJ]

Before I start with my half-baked and half-edu-ma-cated questions, are there any Gunners Mates (SW) floating around here who can shed some light here?

Awhile back a select few (we won't mention names, you know who you are) were crying for dispersion from bombers (apparently they want a shotgun pattern, 1st bomb dropped lands the farthest forward etc), and shifted thier pleas to include the 8" guns on the CAs.  Somewhere I picked up the impression that it was added to shut up those select few because there wasn't any major opposition to it (that I recall anyway).

So, would these 8" guns really disperse the way they do in the game?  I've spent a fair bit of time in the big guns (and pushing squaddies into being forward controllers ) and I've seen what appears to be crazy stuff from the guns.  Sometimes all 3 shells go out nice and straight and stay the same distance apart as the barrels that fired them.  At the other end of the spectrum I've seen the shells cross up so that the #1 projectile looked like it was fired from the #3 barrel, #2 projectile from the #1 barrel, and the #3 projectile appeared to have come from the #1 battery (I usually man the #2 battery).

It doesn't seem logical to have this on these guns, and I'm asking in hopes of learning something new.

The dispersion of a machine gun comes from the bucking/vibration caused by the rapid recoil of full automatic fire.  I've fired full auto weapons and have seen it.

But these guns aren't full automatic weapons.  They're more akin to a single shot or bolt action rifle.  With my Weatherby .300mag the only dispersion it has comes from me (breathing, pulse, squeezing the trigger too quickly, etc).  In essence aren't the 8" guns just extremely large single shot rifles?

And if dispersion is supposed to be applied to the single shot type of weapons why doesn't the panzer's 75mm have it?  As long as I lay my aiming point on the same point for every shot I hit the same place every time.  Come to think of it I don't think I've seen any evidence of dispersion from the 5"/38s either.  And they fire much more rapidly than the 8" batteries do.  Don't man shore batteries verra often so I don't know about them, but judging by the way I've seen them hit ships I've been manning guns on I don't think they have dispersion effects either.

So why do the 8" guns have dispersion?  The rolling of the sea?  Aren't the guns stabalized to account for that?  And even if not, wouldna it affect all 3 barrels/shells equally (since in AH all 3 barrels fire at the same instant)?  That would certainly explain a shotgun pattern in the area the shells are landing, but not why the tracers cross up like they do while in flight.

Ok, Gunners Mates, fire away!
Everyone else just be quiet.

[MANDOBLE]

Dont forget the dispersion for the biggest guns: 1000lb bombs.

[CavemanJ]

Erm... Mandoble... this thread is about the 8" guns on the cruiser and wondering in the world they have such crazy dispersion.

It's not about bombs of any size.

[eskimo2]

Good points cave.

eskimo

[Phantom4]

All ammunition fired from all weapons have dispersion.  When testing ammo manufacturers use "test" barrels which are in effect very heavy bolted down barrels that should minimize barrel and aiming variations. Numerous rounds are fired and dispersions are analyzed.  Variations in projectice wieght, powder wieghts, slight vairations in the chemical reactions all contribute to dispersion.  In actual use, more factors, barrel heating, barrel warpage when fired, atmospheric variations added numerous additional errors.  So could shells cross when fired in salvo - yes but not to much and not too often.  In fact, main guns are seldom fired simultaneously but in specify patterns to maximize rate of fire. and to minimize recoil effects (and barrel heating).

[Don]

>>So why do the 8" guns have dispersion? The rolling of the sea? Aren't the guns stabalized to account for that? And even if not, wouldna it affect all 3 barrels/shells equally <<

Caveman:
I'm not a gunners mate but like shooting the big guns at targets. I just want to add the weirdness I see when a CV or Cruiser is turning. When this happens and I shoot, the shells will turn away from the direction I shoot. Often the turn isn't that drastic or fast a manuever but, the affect on the shell is drastic. The shell leaves the barrel nice and straight but, as it reaches it's apex it turns away from the direction I shot in.  I adjust for this by placing the site to the right or left of my target and account for the turn. Its not exact and takes a few salvoes to get the range and direction but, it works.

[CavemanJ]

Don I think it just appears that they turn because of your motion.  I've never had shells land other than where I aimed then because they turned in midair, but the tracers do look weird sometimes.

Phantom4 back in my younger days when I went to the range 5-6 days a week I could shoot a group with my .45acp you could cover with a quarter.  At 25yds.  That dispersion came from a fairly quick rate of fire, not from the gun.  But we're not talkin about rapid fire weapons here.  And we're not talkin about any plane jane weapon/ammo you can walk into any gun store/show and buy.

We're talkin about, for an intents and purposes, single shot weapons.  Those 8" guns were designed to put a shell in a specific place.  Just like a rifle, if you aim it properly you hit your target.  My brother has a Weatherby .300mag just like mine, and one of his favorite 'tricks' is to stick quarters into a rail and shoot'em from about 200yds.  He punches every one dead center.  It's down right scary.  No dispersion there, or if there is he's figured out how to predict the randomness of it and account for it in his aim.

As for shells crossin when fired in salvo, I don't know how often the USN will fire in salvo or fire each barrel singlely in order.  One of the reasons I specifically asked any Gunners Mates to chime in.  I do know that the photos I've seen of a BB letting lose with all 9 barrels at once are some of the most impressive ones I've seen

[lord dolf vader]

hi cave

 i have no experience with 8" guns but the 5"50s we had on the virginia had a pretty standard dispersion  at the max range 8 miles or so we landed um in a approx tennis court size .( i was a operations specialist and got to do plotting for gunnery.marines dontl like the wild ones ) our  aft cannon was never as accurate as the forward one .(probly the barrel, also one was always brokedick so we didnt give um equal use. when they bombarded beirut the fore gun was out and the aft  one fired for days on end almost all the ammo on the ship ( probly 3k rounds although im not shure )was gone and i dont think the barrel had been replaced) and about one out of 10 rds would have 10 times the dispersion of the other 9 . all of our ammo was marked 1943-1945 so it was old and i think that when the rounds were stored horizontal for a long time the powder settled on one side maken um out of ballance, at least that was what the gunners chief thought. also those rounds get handled alot every time the ship goes into the yards all the ammo is shleped off the ship by general crew they get banged around alot and in 46 years thats alot of handeling. alot of dispersion is caused by not perfectly balanced ammo if you go from regular store bought to match grade bullets it makes a big difference in a regular rifle.

not shure if it helps .

[Don]

>>Don I think it just appears that they turn because of your motion. I've never had shells land other than where I aimed then because they turned in midair, but the tracers do look weird sometimes. <<

Cave:
Nope, I swear it happens a lot. I shoot at my target and sure enough at the apex and begins to drop it goes off from where I shoot. I thought the turn of the ship wouldnt matter much but it does.

[pbirmingham]

Originally posted by Don

Nope, I swear it happens a lot. I shoot at my target and sure enough at the apex and begins to drop it goes off from where I shoot.

Wind?  Or does it only happen when turning?