accuracy of a mortar

[Chad Harrison]

unfortunatly in my life i have not fired a mortar (growing up my dad had a full auto m16 though! at 10 yrs old you cant be that!). from what i read though, direction obviously the easy part, but then you had to figure out the range. if it went to far, raise the tube; if it fell short, lower the tube. but once one landed on your target, keep it there and fire them in rapid succession. (if you have a specific target like a gun) then the only thing that would throw the round off by a far distance would be a gust of wind or i assume the blast of the propellant might thow it off at times (??)

is that all pretty correct for those who know more about mortars? it just seems to me that in the game the mortars are pretty random with their rounds. one will land short, the next long, the next even shorter and so on. it seems that only once and a while one hits home. or is this accurate of what happens with mortar rounds? from what ive read i recall that they would bracket the target, and then lay it on them.

along the same lines, was the 60mm mortar really that wimpy? how big were those rounds?

[Gyrene]

Chad, remember that the base plate of the mortar shifts quite a bit as the mortar is fired and that the tube heats up during prolonged firing, also adding variation to the mix.

Mortar rounds are pretty slow moving compared to rifle rounds, so the wind and weather has more of an effect on mortar rounds.

An experienced crew with a direct line of observation to the target can be very accurate, though.

Gyrene

[Chad Harrison]

<blockquote>quote:</font><hr>Originally posted by Gyrene:

Chad, remember that the base plate of the mortar shifts quite a bit as the mortar is fired and that the tube heats up during prolonged firing, also adding variation to the mix.

Mortar rounds are pretty slow moving compared to rifle rounds, so the wind and weather has more of an effect on mortar rounds.

An experienced crew with a direct line of observation to the target can be very accurate, though.

Gyrene<hr></blockquote>

thanks Gyrene, hadnt thought of the base plate moving; and i knew that mortar rounds had a slow trajectory speed, so wind would play a greater role on the impact location.

but as you said,

<blockquote>quote:</font><hr>An experienced crew with a direct line of observation to the target can be very accurate, though.<hr></blockquote>

so do you (and others) think that this is modelled well in CM?

what brings this up is that i almost always play as the amis. i like to buy infantry at the company level, which comes with 3 60mm mortars. in my PBEM games i have noticed how inaccurate these guys can be at stationary targets (squad/gun) and ESPECIALLY at moving targets! i dont even bother targetting infantry moving in the open. all youll see is your rounds landing a long ways from them. and i usually direct fire them as opposed to spotted fire.

is the CM mortar accuracy accurate?

[Herr_B]

Well enough I think...

Sometimes the shells land to much on target and sometimes to far from target.

I don’t have any experience with mortars so I wonder what kind of aiming equipment does the mortar crews have or in this case did the mortar crews have in WWII was it designed to aim at moving targets?

I know that hitting a moving target with a weapon that fires a rather slow shell is quite hard without good sights, in this case the Swedish army’s bazooka or panzershreck that I fired numerous times during my military service. And that fire as we all know in a much lower and shorter trajectory than a mortar and that means less time to target. With the high trajectory of a mortar it must be insanely hard to hit any thing that moves with the first shell and if you miss that one you'll probably have a hard time since changing direction and elevation on a mortar seams a bit, missing English word here so I'll have to say problematic.

Maybe that wasn’t all that valid but it was the first thing that I thought of…

Patrik

[Chad Harrison]

<blockquote>quote:</font><hr>Originally posted by Patrik:

I don’t have any experience with mortars so I wonder what kind of aiming equipment does the mortar crews have or in this case did the mortar crews have in WWII was it designed to aim at moving targets?<hr></blockquote>

danke patrik. du bist sehr helpfull.

has anyone ever seen/used the sights on a WWII era moratr? are they a simple put the target in the crosshairs and then calculate range and tuble depression?

[Desertor]

I think there was only a tube attached to a plate and to legs to estabilize it, no crosshairs or sight device...

[Desertor]

i mean "two legs"

[Doug Beman]

I've found mortar to be very inaccurate. No matter how I pack it together, when I throw it it just flies apart at spatters all over everything.

DjB

[Herr_B]

<blockquote>quote:</font><hr>Originally posted by Doug Beman:

I've found mortar to be very inaccurate. No matter how I pack it together, when I throw it it just flies apart at spatters all over everything.

<hr></blockquote>

My experience is that they can hit things but most of the time they just hit things when you want them to shoot all over and shoot all over when you want them to hit things.

But I can remember a recent ocation when 3 60m

m all hitted (hitted can't be the right word but it's 30 min past midnight where I live) a squad moveing in wood at the same time and never stopped to hit (hit it's always hit) it, the squad was dead in less then one turn. NICE

[Chad Harrison]

<blockquote>quote:</font><hr>Originally posted by Patrik:

My experience is that they can hit things but most of the time they just hit things when you want them to shoot all over and shoot all over when you want them to hit things.<hr></blockquote>

amen to that. so its not just me.

<blockquote>quote:</font><hr>But I can remember a recent ocation when 3 60mm all hitted (hitted can't be the right word but it's 30 min past midnight where I live) a squad moveing in wood at the same time and never stopped to hit (hit it's always hit) it, the squad was dead in less then one turn. NICE<hr></blockquote>

could you please give me the names, Social security numbers, and rank of each of those men so i can buy them next time.

[JasonC]

Actual WW II mortar procedure was to try to get a 50m "bracket". Meaning, if a round was more than 50m long or short (and if you could tell, which wasn't trivial), then you'd adjust for the next round. Once a round looked like it was within 50m, or if you saw a round land on either side (over and under), then you'd just fire for effect from then on.

The random scatter of the shells made trying for more than that pretty hopeless. You couldn't tell from one round to the next whether it was the point of aim that was off, or just how that one happened to fly. So, within 50m, you'd just fire off shells as fast as they could go down the tube, and count on their random scatter to put at least some of them near the target.

In CM, you can generally expect about 1/3rd of light mortar rounds to land close enough to a point target to do something to it. A 60mm mortar will generally hit 2-3 people over its ammo load, and will usually break a team or HQ sized unit, or pin a squad. If you shoot two at the same target at once, you will often break it with one turn of fire. Once you see their heads go down, you can switch to another target if you have more. They are best used to suppress guns or MG teams (rather than larger full squads) that can hit your regular infantry.

[Pak40]

I'd like to add that a longer distance to the target will make the mortars very unaccuate, especially with the 50mm and 60mm. However the accuracy will improve with more rounds firing at the same target, just like when a tank fires after it's first round.

Direct LOS will help with accuracy as would the experience of the crew.

In one MP game that I played, I massed about 9 60mm mortars (vet and reg mix) on the backside of a large hill and I had a platoon leader do the spotting from the top of the hill. Through out the game, as my opponent opened fire with various fixed guns (mostly 20mm). I KO'd at least three of them with my mortars at a range of 300-400 meters. Other rounds hampered HMGs. With the aid of the 60mm mortars, my M-18s and priests could move without too much worry. And because the guns were KO'd by the mortars, I could use my Heavy Artillery against his troop concentrations instead of the AA guns.

[Ligur]

When doing military service, among other things I was trained as crewman for a 81mm. We had a team of sergeants who did the math when an order to fire came, and then we ran with the mortar pieces, dug the base in (the biggest guy rammed it into soft sand, the site of the firing position was pre-planned. Very important, with the base!) and assembled the mortar which took under a minute. Then the fastest guy spinned the tube to the right direction using two cranks or levers if you will, the other for turning the tube left and right, the other for setting the tube low or high enough. After a ranging shot someone, most often me, would bang in grenades as fast as possible. I don't remember many details since I wasn't so excited about my military service, but at best I think I had 7 grenades in the air at the same time when we were shooting at something like 1.5 kilometers, then we ran out of grenades, damnit. Anyhow, the scatter wasn't large, every round landed inside a 60m x 60m square I believe. Another time we fired a series similar to this, in the purpose of scaring conscripts, and shot a salvo which gradually came closer in 20m leaps, the range was something like 1400 meters, which is quite accurate IMHO. The guys were in trenches, watching from... goddmn my memory, was it 350 meters, and one pissed his pants?

About us hitting, say, visible moving targets... No way. But hitting a target accurately wasn't a problem, given a little time to do some math. Pre-planned targets, and you could count on us to deliver a round there after the ranging shot.

But again, we were just kids doodling with a mortar under the watching eye of a CO. I can't say anything informative about the whole matter.

In CM I find 81mm and 60mm ON MAP launchers very accurate, when I get a line of sigth with either the mortar or a HQ, the target will suffer. Especially the 60mm is accurate as hell. Recently shot a 60mm round inside some open topped big gun in TCP/IP.

On the other hand, a regular FO directing a 120mm mortar is so inaccurate I will never, and I mean never buy one again. It is not worth it with the cost, not that much ammo and the spread is something like 250m x 250m area. WTF? One of my FO's shot himself in the head, for ****s sake.

Why is this? I never heard the accuracy will detoriate dramatically with a 120mm mortar.

The 81mm FO has more ammo, and can suppress a target for a while with more accuracy, and more usefully shoot a veil of smoke! Yay! If you want to suppress a patch of trees with an enemy platoon in it, I most often have some success with the 81mm. I also have used it to suppress enemy guns. Destroy? No. But it correlates well on how I felt firing a 81mm myself, regarding accuracy.

[ 11-26-2001: Message edited by: Ligur ]</p>

[Ligur]

<blockquote>quote:</font><hr>Originally posted by Chad Harrison:

along the same lines, was the 60mm mortar really that wimpy? how big were those rounds?<hr></blockquote>

According to the CO who trained us, yes. He said the 81mm is starting to get useful for scaring the enemy by causing some injuries, but below that its a mind thingy. You feel better since you have "support" and the enemy feels worse with some shrapnel and *boom* sounds near them.

[offtaskagain]

<blockquote>quote:</font><hr>Originally posted by Ligur:

On the other hand, a regular FO directing a 120mm mortar is so inaccurate I will never, and I mean never buy one again. It is not worth it with the cost, not that much ammo and the spread is something like 250m x 250m area. WTF? One of my FO's shot himself in the head, for ****s sake.

Why is this? I never heard the accuracy will detoriate dramatically with a 120mm mortar.

<hr></blockquote>

Better ask Scipio about those, he served on a 120. My grandpa's brother was an FO in the mid '50s and spent most of his practice time at ranges directing 81mm and 4.2 inch mortars. He told me he found mortars to be accurate enough to go after individual MG emplacements.

[Wreck]

Regarding mortars in CM: the effect of off-board artillery in CM is proportionate to the "blast" number squared. You pay an amount linear in blast times shots. The result is that low caliber stuff sucks in bang:buck, all other things equal. Other things are not equal, though: time to target is free and thus big mortars are bargains. Other heavy arty is good (and great for Americans w/ their fast time to target). Little mortars suck, except for smoke chucking.

On board mortars work somewhat differently than offboard one, but I suspect that their effect is still likely to be proportionate to blast^2, while their price is linear in blast. It is also computed in a rather silly manner which, among other things, devalues the ammo load and values the number of crewmen. The upshot of this is, that on-board mortars suck, excepting the 76mm.

On the historical effect of mortars, I think they were more effective than you typically see in CM. Part of that is blast ratings -- at least one mortar shell is arguably undermodelled. I don't know about the 60mm in this regard though. I expect that in WWII most 60mm teams would have more than a handful of shots, at least in a typical defensive or planned-attack situation. In CM you get the amount of shots you can carry.

[Jeff Duquette]

Just to add to Ligur’s and Janson’s obviously informed posts (great post Ligur)…more TFT information. Single tube…dispersion resultant from systematic error only:

M29 81mm Mortar firing HE (charge 4):

@1000m…Range Probable Error = 7m…. Deflection Probable Error=4m

50% Zone = 14m x 8m…. 100% zone = 56m x 32m

@1500m…Range Probable Error = 9m…. Deflection Probable Error=4m

50% Zone = 18m x 8m…. 100% zone = 72m x 32m

[Monty's Double]

Should ground conditions affect mortar accuracy? In the Falklands the soft, peaty soil meant mortars would bury themsleves. I remember reports of Paras firing in support of the Goose Green assault bracing the 81mm mortars with their feet and ending up with broken ankles from the strain. I'd guess prepared defences would suffer a lot less than a mortar which has been hauled forward in support of an attack.

[Herr_B]

<blockquote>quote:</font><hr>Originally posted by Monty's Double:

[QB]Should ground conditions affect mortar accuracy?[QB]<hr></blockquote>

This made me think of someting what does the marsh in CM represent (or means if the word marsh is a well defeind ground state that I don't know about). When I hear the word I think of someting ranging from moist to almost lakelike.

And since I've never trid (IRL) to fire a mortar is that a good thing to do in a marsh?

[Hensworth]

I always group my mortars under an HQ unit. A single mortar doesn't pack much of a punch, but when you've got 3 or 4 of them it's a different story.

I usually pick 1 target for such a battery, have them expend all their ammo on it (which usually achieves excellent results, on an AT gun you can bet on a kill) and then scuttle them to the rear out of harm's way.

In operations this is definitely the way to go IMHO, because you can do this again in every battle and keeping them safe is important.

[ 11-27-2001: Message edited by: Sgt_Kelly ]</p>

[Chad Harrison]

great posts from everyone, thanks! it seems the concensus is that they are undermodelled in CM. how many losses did the allies take from mortars ALONE in normandy?

does anyone know if mortars are going to be modelled any differently in CM2? more FP? more/less accurate? breaks troops easier?

[Beltfed]

Originally posted by Chad Harrison:

[QB] but then you had to figure out the range. if it went to far, raise the tube; if it fell short, lower the tube. but once one landed on your target, keep it there and fire them in rapid succession. (

Hey Chad,

I was what the US Army calls an 11 Charlie or mortar crew fer awhile in the NY National Guard.

I got too bored and switched over to plain infantry but fer about a year I was in mortars.

The aiming stuff is more or less ok. Mortar rounds (at least the 81 we had) have bags of propellant. Some have disks like prepackaged coffee filters that go around the shaft of the round below the war head. The 81s had 9 bags hung around the base long sides parrallel to the length of the round. To hit different ranges we'd also remove the bags so as to provide us with more options in trajectory. SO a typical fire command might go like this:

"Deflection one zero two!" We'd repeat it back to the caller to make sure we got it right

"Elevation, Six Zero!!" again repeated

"One round, HE quick. Charge five!" We'd repeat the info as it was yelled to us and remove four of the propellant bags..leaving...5!

"Hang round!" We yell back, "Hanging round!" and hold the round over the end of the tube.

"Fire!" and we'd drop the round into the tube

Then we'd yell "Round out!" as it slid down and was fired. And whoomp! it would go down range.

We'd repeat the process until the we hit the target then the FDC would yell the commands again but with the words "Fire for Effect!" and how many rounds htey'd want. We'd then shove as many rounds (safely) as fast as we could fer until stopped.

Mortars can be very accurate. With a good crew you can be up and shooting very quickly.

The fun stuff is when a round didn't fire. Uh then things got very interesting

FInal FYI. Unlike many movies mortars are loud! None of the little 'choompfh' sounds ya hear in the movies!

Hope that answers yer questions

[ 11-30-2001: Message edited by: Beltfed ]</p>

[Andreas]

Don't know about undermodeled. I have great success with the Commonwealth 2" mortar. Works every time, if you use it right, and does exactly what it says on the tin.

Regarding casualties from mortars - yes the Allies took a lot. But there are also a lot of accounts of mortar rounds hitting very close to slit-trenches, with no harm to the guys inside.

Really I think that is not a fair comparison. One seemingly standard practice for the Germans was to zero their forward defenses (well shown in episode 3 of BoB), and when they retreated to the fallback position, let the attacker have it. Since that would catch the attacker in the open, it would be painful. Basically, I find casualties as they currently are believable, for want of a better word.

Anyway, I am also clueless WRT mortars, and can only judge this based on reading and game experience. Great post Ligur.