TL3 shields work as cover vs modern rifles?

[weby]

As a large shield like the roman ones are a meter high and 2/3 wide, they fully cover the body when just held, though they do not give any DB against firearms...

So a modern trooper firing at legionaries would according to gurps have to aim at heads/legs or hands as a assault rifle will not damage the chest.

An m16 will do 5d dame that is on average 17.5. Whereas the shield has a DR of 9 and 60 hp and according to the breaking shields rules is penetrated on HP/4+DR, thus with 24 points. Add the RD 5 chest armor and the total raises to 29 that requires one to roll five sixes to penetrate one point.

And on everage would need 7 hits to eat away the hitpoints of the shield. (60/(17.5-9))

Now take situation 2: same large shield, but iron version, with the enemy crouching behind the shield as to not give targets: to damage him would require: DR 12+ 120/4=42 points.. that is impossible to get.. so only eating though the shield HP will work.. that takes on average 21 hits.. (120/(17.5-12))

Situation 3: a 50 cal HMG from basic set raking a group of enemies from situation 2 that have a heavy steel corselet and heavy plate arm:
effects of those rounds that hit:
no penetration of shield: 26%
no penetration of shield+arm/torso armor: 42.5%
less that 10 hp damage(max 5 pentrate armor), so likely survive: 21.5%
more likely deadly(6+ points penetrate armor this 12+hp damage): 10%

Somehow.. seems bit wrong..

[benz72]

There is a difference between penetrating a shield to do damage to whatever is hiding behind it and damaging the shield to destroy it.

[hal]

I've remarked in the past on how the DR and HP values of the shields in GURPS 4e seem a bit out of line. Others have also noted the issue and made their own comments upon it. Just for giggles, I used the rules given in GURPS 4e for calculating hit points of objects based upon their weight and target type (ie whether it was homogenus or what have you). The formula for hit points would thus be 8 x cube root of 15 for a 15 lb object. Ironically, such a medium shield according to the rules given, should have a HP value of at best 20 if you round the value from 19.7 upwards, or 19 HP if you take the integer value. Yet, GURPS assigns a HP value of 40 with a DR value of 7 for such an object.

Try your formula with a 'Corrected" value of 20 HP instead of 40 and see where that gets you. ;)

Also, try a corrected value of 23 HP for the tower shield and see if that gives you values closer to what you might expect. As for myself? I've never been happy with the shield rules given in GURPS 4e to the point where I don't use them. I use the 3e version of the rules for the most part.

[jacobmuller]

The HP of shields is double the basic value; design and construction.

Doesn't stop it seeming very wrong that a 5.56 won't penetrate. Especially if this Wiki quote is correct and not just hyperbole:

Tough though it was, it seems the scutum was not enough to stop arrows loosed from the composite bows wielded by Parthian archers. Plutarch described this at the Battle of Carrhae: "And when Publius urged [the legionaries] to charge the enemy's mail-clad horsemen, they showed him that their hands were riveted to their shields [by arrows] and their feet nailed through and through to the ground, so that they were helpless either for flight or for self-defence."

5.56 does 5d6. Composite bow does Thr+3, that's maybe 1d+3. Gotta be a reason for the discrepancy. Maybe Lo-Tech has a fix...

[Xplo]

I'm not really an expert on the subject, but...

AFAIK, real shields were quite easy to damage. After all, they had to be made of existing materials, and they had to be light enough that you could carry them around and use them effectively (even a tower shield had to be lugged around the battlefield). If I'm not mistaken, it was generally expected that a shield would be hacked to bits by the end of a fierce battle.

In this modern enlightened age, though, shields are often thought of as something that's indestructable. I mean, you use them to block swords and axes, right? They're all made of shiny, heavy duty steel, right? I suspect RPGs borrowed from that notion, since shield destruction and shield penetration rules seem to be pretty uncommon. Perhaps the quoted GURPS stats are some kind of compromise.

[Ulzgoroth]

Only they're not made of shiny heavy duty steel. Not unless you use that option, which makes them much heavier and more expensive. If you want a 50 pound iron scutum, go right ahead...I won't be all that surprised by it stopping bullets, either.

A more reasonably constructed shield doesn't seem like it should be doing that, though. Possibly cover DR should be based on less than 1/4 HP due to the shape?

[Green-Neck]

i've googled the scutum, and they were made of laminated birch [plywood] from 6-12mm in thickness.
i've got a .223 and some spare 12mm ply - so i can test it if you want - i'm just wondering how to test the remaining energy in the round after penetration without the expense and trouble of balistics gel. any ideas?
also my 22 long rifle with subsonic HP rounds 1d-1 pi [0.5] will penetrate 12mm ply. it has only 98 foot pounds of energy vs. the .223's 1280
it sounds like the rules are failing a reality check if a .223 is not harmful to a legionary.
a .223 can reliably penetrate 5/16 steel plate at 25 yards. a scutum in 5/16 [8mm] steel [which was unavailable to the romans obviously] would weigh about 126 pounds.

[bstubby]

Green-neck: A stack of wet newspapers or phone books will give you a rough approximation of relative penetration. Key word being "relative" :)

On page 408 it says that for thin objects like doors or walls only the DR counts (no HPs). Shields certainly seem to fall within that realm.

[Green-Neck]

Ok, i'll get some phone books!
i'll do it tonight [ 6 hours away] when it cools down, we just had a week of 43+ deg C [110 f] days here in southern Oz! any other suggestions?

perhaps i should put 1.5mm mild steel behind to plywood to simulate the lorica segmentata, i don't have any brass sheet!

[Nymdok]

this link may provide useful qualitative penetration values

http://www.theboxotruth.com/

As it turns out there is a guy in Texas who gets paid to shoot suff. Texas is awesome :)

Nymdok