IG18 - seeking hints and tips

[womble]

So I've just been handed a brace of IG18 by a scenario, and I'm having the Devil's own time trying to decide how to use them. Even trying to set them up for preplanned bombardment, whole areas of the map are "no LOS" for no discernible reason. I tried a test scenario out to see what sort of use they were as indirect fire assets, and about 2 of the 15 rounds from each gun actually made it far enough downrange to count as spotting rounds, with the rest hitting various foliage.

I'm struggling to see how they can be used on the offensive (that's what the scenario requires of me) as towed pieces (or hand-pushed at "Normal"), though I've figured I can get two minutes' firing out of each if I position the ammo bearers out of sharing range when I give 'em the first mission.

So how have people successfully deployed IG18s on the attack in CMBN? Indirect fire assets or close support direct HE? Did you fiddlearse about with trucks, or handball the things into hedgerows like really bulky MG42s?

[womble]

Some additional fiddling shows the gun can be towed by a Kubelwagen, which might make less of an obvious target than the truck it comes with, for getting it into useful positions in a timely fashion.

[c3k]

I've tried both techniques. Remember, if you're going to use it for indirect, it is more likely to hit intervening foliage. I find it's usually right over the heads of my own troops. So, for indirect, find an open spot with no obstacles for a GOOD distance out front.

For direct, I _try_ to keep them far enough back so they've not targeted by enemy small arms or squad level mortars.

I'm often not successful at either endeavor.

Ken

[womble]

Thanks for the tips, Ken. I think I'm going to have a go at using them a bit like MG42 on steroids (or poor-Heer's PzIV) to be stooging around behind the Schwerpunkt and brought forward to suppress/break strongpoints. With some judicious positioning/displacing of the ammo bearers I should be able to have the guns fire "short controlled bursts" rather than loosing off their entire stock in one minute.

In the scenario in question, the gun teams seem to be short a man, which means I can fit the crew and bearers into one Kubel, if the bearers do the driving. Which is neat.

[Michael Emrys]

I think I'm going to have a go at using them a bit like MG42 on steroids (or poor-Heer's PzIV) to be stooging around behind the Schwerpunkt and brought forward to suppress/break strongpoints.

I think this is how they were intended to be used (at least early in the war), although I have not been able to find a lot of documentation confirming that. My guess is that after the midpoint of the war, when the Germans were on the defensive most of the time, they were held back behind the lines and used indirectly. But once again, documentation is extremely scarce.

Michael

[Boche]

Thats a question that has been bugging me for sometime, trying to find out what was their purpouse. The only thing I can come up with is that they where supposed to be used as some sort of light assault gun to target enemy strongpoints, giving the infantry some punch without a stug or panzer, and maybe use it as an indirect firing gun sometimes...

because as far as I see, they are not a good indirect fire weapon and are not good antitank weapons...

[YankeeDog]

Thats a question that has been bugging me for sometime, trying to find out what was their purpouse. The only thing I can come up with is that they where supposed to be used as some sort of light assault gun to target enemy strongpoints, giving the infantry some punch without a stug or panzer, and maybe use it as an indirect firing gun sometimes...

because as far as I see, they are not a good indirect fire weapon and are not good antitank weapons...

That's probably more or less accurate. Bear in mind that it's a weapons system that was originally designed at a time when (a) most of the army's heavy weapons were expected to be moved long distances by human or horse power alone, and ( most tanks had relatively light main guns, with limited HE blast.

[DavidFields]

I always thought of an IG as "gee, wish we had a MkIV around, but since we don't, we will us this".

(MkIV is my favorite tank--so darned practically useful with a german company. Forget that tank-on-tank stuff, bring in the direct HE)

Blasting a suppressed strongpoint--particularly one relatively resistent to mortar fire--would seem to be its best use.

But I have no documentation for that.

[winkelried]

That's probably more or less accurate. Bear in mind that it's a weapons system that was originally designed at a time when (a) most of the army's heavy weapons were expected to be moved long distances by human or horse power alone, and ( most tanks had relatively light main guns, with limited HE blast.

that's an important point - by 1944 the IG18 was pretty "outmoded". that's why StuG were used (if available) in an assault - or similar mounted weapons like the short 75mm on Sd. Kfz 251 or the heavier 150mm IG like the Grille. By 1944 in a lot of units the IGs seem to have been replaced by 12cm mortars - at least on paper.

[MikeyD]

Another tip is to try to use them in direct fire as far outside of small arms fire as humanly possible. That can be quite a problem on close Normandy hedgerow maps, and with the long reach of those Garands and BARs. A hill on one corner of the map with a view of an occupied village on the other corner would be nice... except expect to be mortared to death.

[Chris Ferrous]

I've tried IGs just once, in a random QB early on, and IIRC their set-up/pack-up time is about 3 minutes isn't it?

How you can set one up with LOS of an enemy that's not already virtually buried in dirt without being detected and taken out first, I really don't know.

It seemed to me, the best use was simply to use them like an old fashioned cannon on defence, say pointing down a lane or into the corner of a hedgerow, then loose off 2-3 shells at the first target before you have to abandon the gun.

[womble]

I've tried IGs just once, in a random QB early on, and IIRC their set-up/pack-up time is about 3 minutes isn't it?

Set up is 55s. Pack up is 1.6min, for the examples in my current scenario. Don't know if that's trimmed some by them being Veterans.

How you can set one up with LOS of an enemy that's not already virtually buried in dirt without being detected and taken out first, I really don't know.

The only situation I'm thinking they'll be useful in the current attack scenario, is if I come across some opposition in a hard building that I can suppress, but not neutralise without HE. I've only got 1 of my 5 Pz4s from campaign start left, and 2 of 5 Panthers are pretty much out of HE having not gotten a reload after the last scenario, so I might be thankful for having the IGs along. Though Assault Teams going in with grenades and autofire has been pretty successful at eradicating opposition without casualties once I get proper suppression established, so waiting for the IG might be unnecessary.

It seemed to me, the best use was simply to use them like an old fashioned cannon on defence, say pointing down a lane or into the corner of a hedgerow, then loose off 2-3 shells at the first target before you have to abandon the gun.

On defence, I can see them being sort of an ATG for infantry, possibly. Pure speculation, obviously, but if they're as difficult to spot as ATG are, it might be possible to get a surprising amount of ordnance dispatched enemy-wards before you're spotted, and even to get away if you don't push your luck and can spare a Kubel to drag the thing down a covered retreat route.

[Chris Ferrous]

Well good luck, womble.

Does limbering up take extra time beyond pack-up or is it instantaneous?

[womble]

Well good luck, womble.

Thanks.

Does limbering up take extra time beyond pack-up or is it instantaneous?

AIUI, the process of packing up results in a Limbered piece. Getting it to its "prime mover" (I don't think anyone's ever called a Kubelwagen a prime mover before... ) is a "Normal" move however far it has to be pushed, I say 'pushed' because I've noticed that when the limbered piece is being manhandled by its crew, they appear to be pushing it, pointed the way it's going, so they'll have to rotate it to push it towards the rear, and then potentially to hitch it to any towing vehicle, I expect. I shall be sure to observe carefully, should it become necessary to conduct any such evolution.

[Pak40]

Set up is 55s. Pack up is 1.6min, for the examples in my current scenario. Don't know if that's trimmed some by them being Veterans.

Honestly, that's not too bad for a gun. And with the current AT gun deployment bug you could just have the crew deploy immediately when it gets to the hedgerow.

[womble]

So I've now fired off the first five shots from each of the IGs I've got. One was just random shelling of a building that looked at me funny, mostly to see how they work, and the other was an attempt to winkle out a stubborn ATG that was scaring my halftracks, though it had been suppressed for about 10 minutes.

The shelling didn't seem to have much effect. 5 rounds in a minute. It's only 75mm, I wasn't really expecting anything great.

The ATG was no more fazed by the IG 75mm HE than it had been by the earlier bombardment from a Panther (with its underperforming HE). It just stayed suppressed. No advantage from a slightly less flat trajectory. Hey ho.

Maybe the next time I use 'em something useful will be achieved.

1min 35s to pack up, and if you have a Kubel reversed right up to the end of the trail, 10s for the now un-burdened gun crew to mount up, including automagically hitching the gun (there's no animation).

[RockinHarry]

Made a bit of testing with the onmap version IG18 "howitzer" and figured it lacks any high trajectory fire capability in this role, unlike in RL where this was its main purpose. Scenario makers better add a pair offmap IG18 for more realism instead (basically a 2 gun section per Inf Btl).

Flat trajectory Indirect fire for onmap IG18 is possible, IF the map/range to target point is large enough and the IG18 positioned behind a small crest or hill, with no intervening terrain features between. Usable ranges then could be somewhere between 500m to max gun range and a FO with proper LOS.

Direct firing for this weapon is/was rather the exception, as is using Wespe/Hummels in sort of "assault gun mode".

My reference resources for IG18/33, is the original german FM 111/2, 130/4a, as well as some other wartime manuals dealing with tactical employment of this weapon system.

[womble]

Cool, Rockin'Harry. Thanks for the info

It's an interesting little system, and surprisingly mobile for a field piece when towed by Kubelwagen, but having had a couple foisted on me in a scenario, I probably won't ever choose to use 'em. On-map, they're short-winded and not very effective, and I prefer a bit more bang than 75mm for my offmap assets.

[MikeyD]

Lieg 18 was rather like the current AT4 in US army use. Sure, its not the fanciest weapon in the world but if an infantryman needs to simply throw a HE round downrange its pretty much all you got to play with.

[YankeeDog]

Made a bit of testing with the onmap version IG18 "howitzer" and figured it lacks any high trajectory fire capability in this role, unlike in RL where this was its main purpose. Scenario makers better add a pair offmap IG18 for more realism instead (basically a 2 gun section per Inf Btl).

Flat trajectory Indirect fire for onmap IG18 is possible, IF the map/range to target point is large enough and the IG18 positioned behind a small crest or hill, with no intervening terrain features between. Usable ranges then could be somewhere between 500m to max gun range and a FO with proper LOS.

Direct firing for this weapon is/was rather the exception, as is using Wespe/Hummels in sort of "assault gun mode".

My reference resources for IG18/33, is the original german FM 111/2, 130/4a, as well as some other wartime manuals dealing with tactical employment of this weapon system.

Hey there,

Do any of your sorces have a figure for the minimum range for high-angle fire (i.e. fire with the barrel elevated more than 45 degrees)? I tried to figure this out a while ago, but wasn't able to find anything definitive. I did some basic trig calculations based on the gun's muzzle velocity and maximum elevation, and ended up with a figure somewhere around 1.5km, IIRC. But this didn't seem right to me. I would think the weapon was capable of high angle fire at a range shorter than this. But I don't know... Maybe not.

[RockinHarry]

Hey there,

Do any of your sorces have a figure for the minimum range for high-angle fire (i.e. fire with the barrel elevated more than 45 degrees)? I tried to figure this out a while ago, but wasn't able to find anything definitive. I did some basic trig calculations based on the gun's muzzle velocity and maximum elevation, and ended up with a figure somewhere around 1.5km, IIRC. But this didn't seem right to me. I would think the weapon was capable of high angle fire at a range shorter than this. But I don't know... Maybe not.

Unfortunately, no. My manuals mainly deal with employment, tactics and crews handling the gun. I lack the manuals for ballistics and ammo, which are pretty hard to find anywhere.

I remember I read "somewhere" that the minimum range for indirect fire was something like 500m or so.

The charge for the various shell types (main one: 7.5 cm I Gr 18,

Fused AZ 23, 6.00 kg) was in fact made of 5 seperate parts and I think there was yet a special charge for longest range. The seperate charges, individually used for particular ranges and fire tasks are 5 discs with following data:

Partial cartr. 1 of 15.5 grams (Ngl. Pl. P. -12)

Partial cartr. 2 of 6.5 grams (Ngl. Pl. P. -12)

Partial cartr. 3 of 9 grams (Ngl. Pl. P. -12)

Partial cartr. 4 of 16.5 grams (Ngl. Pl. P. -12)

Partial cartr. 5 of 24 grams (Ngl. Pl. P. -12)

I´d presume that for lowest range and possible highest angle (of +75°), just charge (disk) number 1 would be used.

The individual charges would be combined for particular ranges (1+2, 1+2+3,...), ect.

That´s all I could dig so far.

[YankeeDog]

The charge for the various shell types (main one: 7.5 cm I Gr 18,

Fused AZ 23, 6.00 kg) was in fact made of 5 seperate parts and I think there was yet a special charge for longest range....

I´d presume that for lowest range and possible highest angle (of +75°), just charge (disk) number 1 would be used.

Ya, that's basically how I tried to calculate the ballpark figure -- I was able to find the Mv for the minimum charge, so I just did a rough ballistics calculation of the range to impact at maximum elevation and minimum charge. Like I said, I came up with a figure somewhere in the vicinity of 1.5km. There's definitely some error in that calculation, because you have to know the aerodynamic properties of the projectile to really make an accurate calculation, but it *should* be in the right ballpark. Just doesn't seem right to me, though...

[ArgusEye]

Using the data from this thread and Wiki, plugging it into my ballistics program, I get a minimum charge, 73 degree elevation range of 470 meters.

[YankeeDog]

Using the data from this thread and Wiki, plugging it into my ballistics program, I get a minimum charge, 73 degree elevation range of 470 meters.

That sounds more like it. Must have forgotten to carry the 2 er sumfink.

[MikeyD]

Here's a fun Polish site with all things LeIG 18.

http://odkrywca.pl/7-5cm-infantriegeschutz-18,413627.html

Apparently max elevation was only 35 degrees so your dreams of mortar-like high angle shoots may be a bit off the mark.