testing on building protection

[GreenAsJade]

There is a huge misconception in general about walls of buildings and modern (i.e. C20th infantry) weapons. First the disclaimer - I am not an expert myself, but my Dad was in the British Army for over 25years. He told me a full calibre (0.303, or 7.62mm) rifle bullet will go through a typical British built house wall at several hundred meters (think 600+). A typical British house wall in this context is a standard double wall with cavety, made of standard bricks on the outside and 'breezeblock' on the inner. This related to well post war. WW2 British would be a double thickness of Brick (minimum 6", or 9" if well built. I do not know Normandy well, but would assume houses were equivalent. The only thing that makes a difference would be a stone built (properly built, not just dressed with stone) house. Thus expecting a house to act as cover is going to be disappointed. Houses are mostly concealment unless fortified (which doesn't happen in game if I understand correctly) ...

Interesting to know. Not intuitive for sure. It seems to meant that there is basically no effective cover anywhere other than behind a berm?

And this argument surely can't be applied to a church/steeple. Those things are made of solid stone...

GaJ

[LongLeftFlank]

As I was recently poring over that well known Green Book detailed map of the Nazi defenses around Le Carillon, I noticed that while the Germans set up CPs in various farmhouses, they aren't shown as containing defensive positions... MGs are set up next to them or keyholed between them. The Germans seem to have preferred digging into the nearby bocage to strongpointing the buildings.

I suppose that makes sense -- they're magnets for enemy fire, especially artillery and while you can certainly reinforce the ground level walls with stacks of sandbags shoring up the roof is another matter. And since these houses were generally inside walled/hedged enclosures, the fields of fire could be restricted as well. That doesn't mean they weren't commonly used as firing or sniping positions in the actual fights (and also booby trapped) but I found the lack of marked fortification interesting.

On the other hand, I do know for a fact that further north the Germans fortified a whole bunch of sturdy stone buildings along RN-3 ("Hell's Highway") including shops, a church and chateau at St Gilles -- not just sandbagging the walls, windows and cellars but adding poured cement bomb shelters and slit trenches as well.

The Yanks basically had to silence them using demo charges and point blank tank/TD direct fire. The 2 day fight for these positions more or less devoured 2 companies of the US 137th Infantry (including the regimental commander) and only 3 German prisoners were taken. Grim stats.

[akd]

There is a huge misconception in general about walls of buildings and modern (i.e. C20th infantry) weapons. First the disclaimer - I am not an expert myself, but my Dad was in the British Army for over 25years. He told me a full calibre (0.303, or 7.62mm) rifle bullet will go through a typical British built house wall at several hundred meters (think 600+). A typical British house wall in this context is a standard double wall with cavety, made of standard bricks on the outside and 'breezeblock' on the inner. This related to well post war. WW2 British would be a double thickness of Brick (minimum 6", or 9" if well built. I do not know Normandy well, but would assume houses were equivalent. The only thing that makes a difference would be a stone built (properly built, not just dressed with stone) house. Thus expecting a house to act as cover is going to be disappointed. Houses are mostly concealment unless fortified (which doesn't happen in game if I understand correctly) ...

The majority of buildings in Normandy at this time seem to have been stone masonry, with walls at least 1-2 feet thick (but often thicker).

[Paper Tiger]

Have a re-read of Keegan's 'Six Armies in Normandy', p99 to 102, (The 1st/505th at the Merderet) if you think that buildings in Normandy shouldn't offer much cover to defending infantry. These stone-buillt farmhouses were veritable fortresses even to WW2 weapons. You needed artillery or armour to reduce these strongpoints. The MG team holed up in the Manor team held up an entire company of US paras and their 60mm mortars were useless against them. In the game, you can kill the defenders in buildings with a single 60mm mortar without much difficulty.

There were a significant number of these stout Norman farmhouses and barns peppered around behind the landing zones and they were significant enough threats to attackers to warrant mentioning. (ibid. p171)

We're not talking about town buildings here which may offer less protrection to a defender.

[Redwolf]

There is a huge misconception in general about walls of buildings and modern (i.e. C20th infantry) weapons. First the disclaimer - I am not an expert myself, but my Dad was in the British Army for over 25years. He told me a full calibre (0.303, or 7.62mm) rifle bullet will go through a typical British built house wall at several hundred meters (think 600+). A typical British house wall in this context is a standard double wall with cavety, made of standard bricks on the outside and 'breezeblock' on the inner. This related to well post war. WW2 British would be a double thickness of Brick (minimum 6", or 9" if well built. I do not know Normandy well, but would assume houses were equivalent. The only thing that makes a difference would be a stone built (properly built, not just dressed with stone) house. Thus expecting a house to act as cover is going to be disappointed. Houses are mostly concealment unless fortified (which doesn't happen in game if I understand correctly) ...

That doesn't mean it should be close to being in the open.

Also, french and german houses are not as fluffy as what the British built at the far end of the gulf stream.

Finally, I'd rather like to see more confirmation of the claim that 7.62 goes right through a double masonry wall and still is as dangerous as outside.

[wolf66]

The MG team holed up in the Manor team held up an entire company of US paras and their 60mm mortars were useless against them. In the game, you can kill the defenders in buildings with a single 60mm mortar without much difficulty

And this is exactly why there has to be something wrong with the buildings in game.......

[LemuelG]

Have a re-read of Keegan's 'Six Armies in Normandy', p99 to 102, (The 1st/505th at the Merderet) if you think that buildings in Normandy shouldn't offer much cover to defending infantry. These stone-buillt farmhouses were veritable fortresses even to WW2 weapons. You needed artillery or armour to reduce these strongpoints. The MG team holed up in the Manor team held up an entire company of US paras and their 60mm mortars were useless against them. In the game, you can kill the defenders in buildings with a single 60mm mortar without much difficulty.

There were a significant number of these stout Norman farmhouses and barns peppered around behind the landing zones and they were significant enough threats to attackers to warrant mentioning. (ibid. p171)

We're not talking about town buildings here which may offer less protrection to a defender.

Have you seen Le Manoire De La Fiere? It's a castle... literally - it has a tall tower with thick granite walls and strategically-placed loop-holes big enough to poke a gun out of, and not much more. There really is no way in the game to adequately represent this. Further west (2km-ish) of La Fiere is Chateau De Amfreville (dubbed: 'grey castle' by the paras - hints at it's nature) has a huge castle-type twin-towered gatehouse and very thick walls, these are the 'stout Norman farmhouses'... small castles, positions built specifically for fighting and defence. I guess castles are sort of like really big, well-fortified farms

The Germans at the manor could control certain fields-of-fire through their loop-holes but were quickly isolated, blasted by a 'zook, and riddled with a tommy-gun through the floorboards then gave up; most casualties in the battle were caused by the MGs hidden in hedges and the causeway outside, and they (the US paras) heavily limited mortar-use because of the proximity of friendly troops from a number of different units converging on the area.

(edit) should mention - German mortaring stoved-in the entire frontal facade of the manoire later D-Day afternoon, it was anything but impervious to mortars.

[winkelried]

As I was recently poring over that well known Green Book detailed map of the Nazi defenses around Le Carillon, I noticed that while the Germans set up CPs in various farmhouses, they aren't shown as containing defensive positions... MGs are set up next to them or keyholed between them. The Germans seem to have preferred digging into the nearby bocage to strongpointing the buildings.

As mentioned above vulnerability of buildings against WW2 ammo seems underestimated by some players - see this thread in addition buildings often have limited fields of view - a spot close by might have a much better one.

but what really seems to be missing are basements where you could get good pretty good cover, but would not be able to see much or even fire your weapons. maybe that's why the CP was located in a building.

[RockinHarry]

While doing some further tests, I figured some visual indications to be somewhat misleading with regard to the protective nature of buildings.

1. Visual window sizes do not always (?) appear to match "internal" sizes of "firing ports". When observing soldiers shooting out of the building, they oftenly appear to shoot through the neighboring walls, which makes me think "internal size" is at least 50% larger (or wider) than what the visual windows indicate. If it is so, then it´s clear, that return fire into a house also offers more of a target behind the invisibly enlarged windows/firing ports. This is similar to bunkers, which have a very wide firing slit, as opposed to a small firing port, most bunkers normally have. I guess it´s all sort of an abstraction to enable single soldiers to find a firing position behind windows better. But as said, it works both ways (incoming fire).

2. Observing tracers from incoming fire (into a house) also makes one think, that many shots penetrate through walls, oftentimes right through all of the house and through the back wall. While it makes one think, these shots make a house swiss cheese, I can rarely observe any such shots hitting or injuring a soldier in a house. Maybe it´s a game limitation that stray tracers through walls are shown at full speed, while internally they should have lost most or all of their kinetic energy, during penetration.

Most soldier hits/injuries appear to come through the abstractedly enlarged windows and not through walls. So if a buildings protective value appears doubtable, it´s less from walls not beeing thick enough, it´s rather from windows/firing ports internally calculated beeing larger.

Best method so far to "fortify" a building: Generally don´t use upper stories as fighting position. Make 1m high berms around a house and just use the ground floor as fighting position. A single building placed "off center" (not filling whole action spots) can be given a protective 1m high berm, by raising all action spots beneath the house by 1m and leaving one action spot at original height (yet touched by the house above). Buildings stick to the lowest action spot they touch beneath. Example: Off center single spot building touches 4 action spots. One is 20m and remaining 3 are 21m. The building sticks at 20m, while the other action spots "partly" raise to 21m, creating the "berm" around the house.

I haven´t experimented that much with "walls" intersecting (or placed within) a buildings 3D geometry, but I think from my obervations, this kind of wall placement is ignored, when it comes to (extra) cover protection. Non intersecting walls, outside a building would add benefits though.

The 1m high berm adds effective cover to the house, unless an attacker has a considerable height advantage off course.

A usable tactic is to let the defending unit blast away at approaching enemies freely and when return fire adds sufficient suppression, the automatic "cowering" makes soldiers more or less invulnerable. Yet incoming fire would be absorbed by the 1m berm. One minute of hide would break LOF to the attacker and with next unhide in coming turn, defenders again receive effective first fire opportunities, unless the whole procedure starts anew. At least works well vs. the AI....

So the main weakness of a building defense is:

(internally) Oversized windows

Too many soldiers bunching up behind these windows (can be solved by splitting squads and diverting teams to different walls with "face")

Soldiers not reloading weapons in prone position or in cover (RL standard procedure).

In case of a HMG34/42, crew members that normally go to cover when the gunner + assistant fight, unecessarily expose themselves, shooting at the enemy, ect.

[womble]

In the game, you can kill the defenders in buildings with a single 60mm mortar without much difficulty.

To start with, I thought 60mm would be useless against troops in buildings, mostly. So I didn't use them that way. Then I thought I'd give it a go. I watched a good dozen 60mm strike the roof of a building (disappearing to apparently explode inside) and thought it must've done for the 7 germans in the house (partly because they weren't exploding on the roof, like other bombardments have seemed to). Didn't kill a single one. Didn't marr the roof at all. It was one of the 2-storey, 3 window-per-side stoney-looking houses. Right hand end of the main row at the back of La Haye du Puits.

[RockinHarry]

but what really seems to be missing are basements where you could get good pretty good cover, but would not be able to see much or even fire your weapons. maybe that's why the CP was located in a building.

Can just speak for what I see in germany so far, but oftenly applies to farm buildings and city buildings as well. Basements, that are not level with the surrounding terrain, having cellar windows slightly above ground, providing an excellent firing position for single LMGs or SMG gunners & snipers. These are hard to spot and hit in return.

[slysniper]

That doesn't mean it should be close to being in the open.

Also, french and german houses are not as fluffy as what the British built at the far end of the gulf stream.

Finally, I'd rather like to see more confirmation of the claim that 7.62 goes right through a double masonry wall and still is as dangerous as outside.

This is the part that gets me also, even if the bullit does penetrate that type of material, what is the flight path and velocity by then.

Well no matter what, the game should have some classifications of buildings so you can tell if it offers cover and there should be a new type that has not been in any of their games and that is buildings which have been fortified.

[winkelried]

Can just speak for what I see in germany so far, but oftenly applies to farm buildings and city buildings as well. Basements, that are not level with the surrounding terrain, having cellar windows slightly above ground, providing an excellent firing position for single LMGs or SMG gunners & snipers. These are hard to spot and hit in return.

Yes this is true for this kind of "half"-basement. On the other hand they are pretty vulnerable to hand grenades or the like - at least we learned to cover the "holes" with some wire-fence - so you still could shoot out - but that at least the first grenade would not come through and fall into the basement ... and the issue with the visibility is even bigger (smaller "window"-size with pretty thick walls).

[RockinHarry]

Since most tests are done comparing US small arms ammo, here´s some data for the common german 7.92mm sS round (schweres Spitzgeschoss).

Taken from german H.DV 316, Pionierdienst aller Waffen, table 12, 1936.

Cover vs. rifle fire at ranges of 400m and below:

earth, sand, clay = 100cm

sandbags = 50cm

grass pads = 120cm

gravel = 20cm

oak wood, round = 70cm

pine wood = 130cm

brick wall = 38cm (no protection vs. machine gun point fire)

And some data from Wolfgang Fleischers "Field Fortifications of the german army, 1939-1945:

This is general guidelines for safe cover vs. enemy small arms, 1944:

stamped snow = 250-300cm

fresh snow = 400cm

ice = 80cm

firm earth = 120cm

loose earth = 140cm

clay = 110cm

sand, rubble = 100cm

soft wood = 90cm

hard wood = 75cm

sandbags = 70cm

soft rock = 60cm

medium hard rock = 40cm

brick wall = 65cm

field stone wall = 40cm

concrete = 20cm

steel concrete = 20cm

Some more interesting data re german 7.92mm sS bullet, taken from H.DV 73, shooting regulation for HMG, page 25/26, 1937:

at 100m penetrates 65cm dry pine wood

at 400m penetrates 85cm dry pine wood (!)

at 800m penetrates 45cm dry pine wood

at 1800m penetrates 25cm dry pine wood

the fact, that the 7.92mm sS penetrates less at 100m is from the bullet misforming at impact with the higher V0, resulting in worse penetration.

Brick walls of single brick strength (25cm), can only be penetrated by single bullets if they hit a joint by chance. With longer shooting and hitting at the same spot, even stronger walls do not provide safe protection.

[LongLeftFlank]

Great thread here -- useful info for a CMBN "fortification how to manual"' Inspiring me to do some testing once I get home.

[Erwin]

concrete = 20cm

steel concrete = 20cm

R U sure that's correct? That's saying 8 inches of steel concrete is required to stop small arms?

[RockinHarry]

concrete = 20cm

steel concrete = 20cm

R U sure that's correct? That's saying 8 inches of steel concrete is required to stop small arms?

yep, straightly taken from Fleischers book. Can´t tell if it´s a typo or not. To be more exactly, it tells of "stamped concrete" and "steel concrete".

Safe protection figures for a direct hit of single 105mm HE (no delay fuse):

stamped concrete = 100cm

steel concrete = 75cm

The tables don´t tell if it´s protection vs. a particular nations small arms, but rather a general guideline for ALL sort of small arms & splinters (rifles, machine guns and aircraft light weaponry).

[winkelried]

concrete = 20cm

steel concrete = 20cm

R U sure that's correct? That's saying 8 inches of steel concrete is required to stop small arms?

I don't know about you - but I served in the pre 5.56 epoch where we had **real** ammunition :cool: - 7.5 or 7.62x51 - and part of the training was to learn what you could penetrate with this ammo - although we talked about 10cm of concrete as far as I remember.

[winkelried]

The tables don´t tell if it´s protection vs. a particular nations small arms, but rather a general guideline for ALL sort of small arms & splinters (rifles, machine guns and aircraft light weaponry).

they probably want to be on the safe side, when constructing a bunker. i think one of the issue are flakes that detach at the interior of the concrete. that's why gravel and sandbags provide some of the best protection - they can move in all directions and absorb the shock of the projectile much better.

[Holien]

Just watched a clip more closely of a German MG Team firing on an American Halftrack directly below them. The MG appeared to be firing through the wall and not through the window. The building was shrugging off SMG fire from an American crew man on path below.

What made me smile is the animation of the German buddy smoking while fighting was happening, one cool dude...

I have not played enough to see effects of the buildings but in previous game I spent many minutes using MG43 onto buildings with Americans in it and seemed to have little effect on some buildings which does seem to indicate some are better at stopping bullets than others, which has already been noted by others....

Anyway great thread and I hope BTS will indicate which buildings are better as this would be pretty obvious as a soldier on the ground.

[LemuelG]

Something worth experimenting with is modular buildings and varying the windows on each facade - you can get rid of all upstairs/downstairs windows and create an attic/basement, giving troops a place to go if things get too hot.

When I wanted to make an unusually strong building I put three side by side in an L shape and made doors/knocked-down walls in the interior as needed so all buildings/levels were connected from within, then I put a tall stone wall around most of it, leaving only two exits open, and a segment of low stone wall to allow a lower level window; most of the windows on the rear and sides were closed to limit the angles from which the troops within can be engaged. It's pretty rough, but hard to assault.

[LongLeftFlank]

In a previous thread, I proved out the resiliency of the large cathedral segments (the 3 story and the 8 story) by bombarding them with 105mm until the Priest ran out of ammo... they took superficial damage only (although the little 1 story village church collapsed rapidly -- very disappointing!)

I have now resumed testing with a "chateau" cobbled together from the second 2 story independent house on the pallette, which looks sturdy enough, together with 2x3 story modular buildings on the corner.

No joy however: both building types took 8-12 105mm rounds each to demolish. Back to the shootin' range to find a house that holds up.

[LongLeftFlank]

...And no joie in Ville de Boue. All 16 independent House types and all 8 Commercial types were totally demolished by between 8 and 12 x 105mm rounds each. No evident variation in survivability.

[Paper Tiger]

Have you seen Le Manoire De La Fiere?

Only in Google Earth and photos from the battle in WW2. Sadly, I live too far away for me to take a weekend trip over to check these sites out in person anymore.

It's a castle... literally - it has a tall tower with thick granite walls and strategically-placed loop-holes big enough to poke a gun out of, and not much more.

Well, it's a manor house, probably a Knight's house from the Medieval period when they built these small fortified manor houses as shelters for the community in the event of a raid or attack. The community could gather within their walls and they were sufficiently castle-like to deter all but a serious attacker. They had stout curtain walls and some had a gatehouse. I'm not surprised that there was a tower. (You can find similar towers on old buildings in Aberdeen in Scotland.) Normandy is blessed with plenty of these fortified buildings. We're not talking about constructing small towns or entire villages with buildings like these but they are certainly not rare in Normandy and one per village is about right. They are present in good numbers in SE England as well and I have been inside them. They are cold and dark inside, even at the height of summer because of the thickness of their castle-like stone walls. And they make very comfortable houses for a single family to live in nowadays.

There really is no way in the game to adequately represent this.

I'm not sure I'd agree with that statement. It's certainly true that we can't adequately represent this at present. I'd just like to see a sturdier structure introduced at some point that would. I doubt that it would be a big deal to do either.

Further west (2km-ish) of La Fiere is Chateau De Amfreville (dubbed: 'grey castle' by the paras - hints at it's nature) has a huge castle-type twin-towered gatehouse and very thick walls, these are the 'stout Norman farmhouses'... small castles, positions built specifically for fighting and defence. I guess castles are sort of like really big, well-fortified farms

Yup, that would be an actual castle and I can assure you that I very familiar with those and am not confusing the two. I am not lobbying for castles to be constructed in the editor. I'd just like to have a stout Norman farmhouse and barn. (I'd also like to have some of the stone walls reskinned so that they look less brick-like. I am familiar with ancient stone walls and the game skins are too modern.)

BTW, the Germans used 81mm mortars, right? I think they are sufficiently powerful to do considerable damage to these ancient structures. Thus the need for 'artillery or armour support' when assaulting these structures. I'm not so sure that the US 60mm mortar was quite so effective but I'm certainly no expert and am very happy to be corrected (politely, of course). We'll just have to wait and see how effective the Brit 2" mortar is against troops in buildings.

[LongLeftFlank]

BTW, the Germans used 81mm mortars, right? I think they are sufficiently powerful to do considerable damage to these ancient structures. Thus the need for 'artillery or armour support' when assaulting these structures. I'm not so sure that the US 60mm mortar was quite so effective but I'm certainly no expert and am very happy to be corrected (politely, of course). We'll just have to wait and see how effective the Brit 2" mortar is against troops in buildings.

First, I happen to believe that the destructive blast effects of garden variety mortar rounds, which were designed to impact on the surface and to maximize fragmentation for antipersonnel purposes rather than plowing into and then blowing up the earth and its contents like artillery shells, are overmodeled in the game (my case is supported by the existence of specialized "demolition" rounds which presumably have a special fuze and thicker casing to delay and channel the blast). But let's let that pass for the moment.

"Damage" also comes in different varieties. As you've said, castle walls were thick, extremely thick, designed to defy the power of rams, pickaxes and catapults. These would also create formidable cover against flat trajectory bullets and shells, agreed, although lengthy bombardment would eventually create breaches (gunpowder is one reason the feudal period came to an end in the 15th century. Also, I believe that most of the obsolete castles were either converted into manor homes or pulled down for quarry, so one per village is probably overstating).

But the roofs would be a different matter -- most likely slates covering a framework of sturdy oak beams. And then there would be oak floors and beams below, assuming multiple stories.

Mortar rounds, as mentioned, would mainly impact on the roof and not penetrate, at least until sufficient slates were smashed to create gaping holes to drop through. And then you'd have to repeat the process on the upper floors. Plunging shells of sufficient calibre though would frequently punch through to explode in the interior.

FWIW