Accuracy values for the main guns - MBT's.

[JaM]

In fact, US Army had accuracy problems during testing german 120mm L55 Gun firing new US APFSDS rounds (M829A2,M829A3)Its accuracy with this rounds was much worse than with M256 gun (L44)

[JaM]

Discusion on Yahoo board is quite big. Accuracy system works great until 1970, after this date new ammunitions are avaiable and this should be taken into account. I know that most of datas are classified, so you need a formula that will work for all tanks with data avaiable. My sugesstion is use L/D ratio of APFSDS projectiles as measurment for accuracy and degree of technology of tank gun. Soviet tank guns were quite unaccurate at ranges over 1600m,they used APFSDS rounds with L/D ratio 10:1 - 13:1,newest projectiles has better accuracy (BM-42,BM-42M etc...)guns that fires them are upgraded so they can fire longer rounds with better L/D (20:1, autoloader prevents to use longer rounds such as US M829A2 or A3 with L/D 30:1 - 37:1).Western tanks started with L/D 10:1 (M735) but they develop better ammo quite soon as M774(not so sure but it is in L/D 15:1 - 20:1 region) M833 (L/D around 20:1) or M900 (L/D 30:1).
Im not suggesting use L/D value as a acc value, but just better variable than lenght of gun.Soviet HEAT ammo for example are stated as more accurate as APFSDS rounds (0,2mil dispersion for HEAT-FS and 0,25-0,3mil for APFSDS)

[Fabfire]

JaM said:
Discusion on Yahoo board is quite big. Accuracy system works great until 1970, after this date new ammunitions are avaiable and this should be taken into account. I know that most of datas are classified, so you need a formula that will work for all tanks with data avaiable. My sugesstion is use L/D ratio of APFSDS projectiles as measurment for accuracy and degree of technology of tank gun. Soviet tank guns were quite unaccurate at ranges over 1600m,they used APFSDS rounds with L/D ratio 10:1 - 13:1,newest projectiles has better accuracy (BM-42,BM-42M etc...)guns that fires them are upgraded so they can fire longer rounds with better L/D (20:1, autoloader prevents to use longer rounds such as US M829A2 or A3 with L/D 30:1 - 37:1).Western tanks started with L/D 10:1 (M735) but they develop better ammo quite soon as M774(not so sure but it is in L/D 15:1 - 20:1 region) M833 (L/D around 20:1) or M900 (L/D 30:1).
Im not suggesting use L/D value as a acc value, but just better variable than lenght of gun.Soviet HEAT ammo for example are stated as more accurate as APFSDS rounds (0,2mil dispersion for HEAT-FS and 0,25-0,3mil for APFSDS)

That's interesting. Thank you. However, I still would like so much to hear from Andy and Don on this subject...

[JaM]

M256 said:

That's interesting. Thank you. However, I still would like so much to hear from Andy and Don on this subject...

Me too..

By the way, i have some numbers about our Slovak modernisation of 2A46 gun (2A46MS) from Slovak military bulletin, gun during tests was 30% more accurate than original gun

[Fabfire]

JaM said:

Me too..

By the way, i have some numbers about our Slovak modernisation of 2A46 gun (2A46MS) from Slovak military bulletin, gun during tests was 30% more accurate than original gun

I am interested in those tests data. Can you post it on this Forum?

[Fabfire]

JaM said:
In fact, US Army had accuracy problems during testing german 120mm L55 Gun firing new US APFSDS rounds (M829A2,M829A3)Its accuracy with this rounds was much worse than with M256 gun (L44)

Yep. I know that. But this was due to the incompatibilities of the new German gun with the US DU APFSDS rounds, that were developed to maximize the potential of the 120mm M256 gun. This does not implies, in any way, that the Rheinmetall 120mm L/55 would be less accurate than the 120mm M256 (a modified Rh 120mm L/44 gun), once the DU ammunition is optimized for this gun.