Graviteam

I was playing around with the m60 the other day and noticed that I could penetrate and knock out m113 apc using only the 7.62 mm MG provided that I fired from close range of about 75 m or less.  From this distance I was able to penetrate the side plate of this APC which is 44 mm thick according to the encyclopedia, way higher than the 7 mm that the 7.62 mm can go through.  Checking wikepedia I read that the m113's armour was designed to protect from 7.62 mm rounds, but was in practice too thin to protect from this threat at close ranges; it seems the armour model in game is consistent with reality.  My question is why the encyclopedia is so far off with regards to the protective capability of the M 113 armour; perhaps it doesn't account for material type (m 113 has alluminum armour) or something like that.

M113 uses 5083 aluminum alloy, it's simple construction alloy, not armor alloy, have efficiency 0,25-0,3 to RHA, it woudnt stop even 5,56 AP from 50 meters, 7,62x54R AP doesn't have any problem with such "armor", M113 designed to stop AKM 7,62x39(not all type of bullets).

7,62x54R B-32 penetrates 10mm steel 2P(high hardness steel for BMP-1/2) at 200 meters

The encyclopedia is indicated only the thickness of the armor, but does not specify its parameters (which are used in the game for calculations). Therefore encyclopedia - is a rough estimate and not an exact. Especially for such exceptions like in aluminum armor.

Aluminum armor sort of blows anyways.  You need quite a lot of material to give the same protection as 8mm of steel armor.  It will also easily ding up if it scrapes along something.  Seen gouges in the sides of m113 series vehicles where it scraped along this or that.  Steel will never do that.  

One other thing i want to point out is that 5.56 armor piercing rounds have more penetration at close ranges than 7.62 AP.  The reason is simple, speed kills armor.  But 5.56 velocity falls off much faster than 7.62 do to a much lighter round.  But a small little tungsten core or hardened steel core 5.56 round close in has a surprising effect close in on light armor vehicles if using steel armor and nothing else.  Its kind of surprising really.  But slap some ceramic titles or other composite on top of the steel and its pretty hard to kill with small arms at even suicidal close ranges. Might even stop some heavy stuff like 12.7mm ball until it falls apart from multiple hits.   Of course I am talking about really light armored vehicles here.  The BRDM's and Commando armored cars of the world.  That sort of thing is only proofed for small arms ball ammo and shell splinters and not AP small arms ammo at rather close ranges. Still needs a rather flat angle to do its thing and a bit of luck and or a lot of rounds.  Far from a sure thing.  Probably not a good idea to run up to a BRDM-2 with a M249 with AP belt and blast away.  But might well work.

Interesting read Flashburn, as always.

Technical information on small arms armor penetration

http://www.dtic.mil/dtic/tr/fulltext/u2/a954350.pdf (http://www.dtic.mil/dtic/tr/fulltext/u2/a954350.pdf)