by78
General
TerraN_EmpirE 220 mm seems few![]()
220mm RHA is the actual thickness of the target plate, not its effective (i.e. line-of-sight) thickness. By sloping an armor plate, the effective thickness is increased. See photo below to get the idea.
TerraN_EmpirE 220 mm seems few![]()
comparison with US rounds, straight on penetration at 2 km
m289a1 (end of Cold war), according to Steven J. Zaloga, penetrated 570mm at 2km. According to Fprado website it could penetrate 610mm.
a2 variant, entered in 1994, pentrated 730mm at 2km, according to fprado.
a3 variant, in service since 2003, penetrated 760mm at 2km, according to fprado
a4 variant got the contract for full scale production in 2016. penetration estimate unavailable.
Would be interesting to know what caused the jump from 600ish to 730mm, between a1 and 2 variants. Allegedly the round leaves the bareel at 100 m/s higher speed than a1 variant. But could that really be enough to explain the jump in performance?
Of course, all these may just be unbased guesstimates by all the said sources.
but not by much. As Below the Tank ring sums upAccording to , the penetration estimates commonly thrown around for the M829A3 might be overestimated.
What impact does this have on the penetration estimates mentioned earlier? According to the patents from ATK, such a design increases the penetration into RHS protected by an unkown type of heavy ERA by 20 to 30% compared to the same penetrator without solid steel tip. Against normal RHS not protected by any form of ERA however the penetration increased only by 5 to 10%, which is to be expected due to the steel tip also prodividing penetration.
The M829A3 might as well be optimized for fighting tanks with heavy ERA such as the main tanks of all potential enemies of the US/NATO - China, Russia, North Korea all utilize heavy ERA on their latest tanks. So instead of having some mind-boggling penetration (for an APFSDS fired with the short L/44 barrel) against all types of armor, the penetration against RHS/composite armor might be as low as ~660 to 700 mm; enough to defeat the main armor of tanks like the T-80U, T-90 and Type 99.
That's the thickness of the plate flat. obliquity is the angle at which the plate is sitting. depending on the angle that could mean a relative thickness many times more. in this case about 600mm.TerraN_EmpirE 220 mm seems few![]()
The problem is though the the more the slopes the harder it is to have internal volume IE Crew, equipment and ammo space. in order to get the same internal space you have to start building the tanks with larger external bodies. after a while it all just falls apart because the weight of the tank keeps going up. Sloped armor was an attempt to keep the tank the same relative weight but with heavier equivalent protection yet the more you slope the more space is unusable.220mm RHA is the actual thickness of the target plate, not its effective (i.e. line-of-sight) thickness. By sloping an armor plate, the effective thickness is increased. See photo below to get the idea.
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Not sure how that solves the problem of "220mm" since to get merely double that effective armor thickness to 440mm with the same plate you have to do some extreme sloping.That's the thickness of the plate flat. obliquity is the angle at which the plate is sitting. depending on the angle that could mean a relative thickness many times more. in this case about 600mm.
When building a flat faced object in a Three Dimensional environment you don't have one angle you have two. the slope from the ground up and from the front back.Not sure how that solves the problem of "220mm" since to get merely double that effective armor thickness to 440mm with the same plate you have to do some extreme sloping.
Not sure what you're referring to, but this is what I'm talking about:When building a flat faced object in a Three Dimensional environment you don't have one angle you have two. the slope from the ground up and from the front back.
