Why is Sherman gun more effective than T34/76?

[Warren Peace]

In unrealistic gunnery ranges the T34/76 is mincemeat for the StugG. (In fact the T34/76 won't even try to engage and will run away instead.) However, in CMBO the Sherman M3A3 (75) generally stood up well and against the STug, killing about as often as it got killed.

As near as I can tell the gun's have almost identical penetrations, so why should this be?

Warren

[Chad Harrison]

From my understanding it has to do with the type of shell used. ie. the material used in the AP shell. Someone will clarify more specifically, but generally before 1944 the Russian AP shells were near useless.

Chad

[Warren Peace]

I thought that might be the case, but if so why isn't that reflected in different penetration values?

[MikeyD]

It might also be the difference between CMBO and CMBB.

I'd like to try CMBO's "Chance Encounter" with Shermans vs Stugs but using the CMBB engine. Chance A "Encounter CMBB" scenario is available at Tom's Combat Mission but was switched from Shermans to T34s. I may alter it to put the Shermans back, see how it runs.

[Dirtweasle]

Related to this is the higher ROF, Gyro-Stabilizer and Fast Turret...

[gunnergoz]

Don't forget 2-man vs 3-man turret.

[jgdpzr]

Post deleted because I misunderstood the original question.

[ November 04, 2002, 01:36 PM: Message edited by: jgdpzr ]

[Amedeo]

The difference lies in the fact that the US 75mm has APCBC ammo while the 76mm gun has APBC ammo.

Since the StuG III has typically not-too-sloped face hardened armour plates, the 75mm APCBC has the advantage of the cap vs. FH plates, while the APBC shell cannot exploit its inherent better performance against sloped armour (on the contrary it's slightly worse than vanilla AP rounds vs. vertical plate).

Regards,

Amedeo

P.S. If you have the same two guns pitted against sloped armour w/o FH, with an equivalent LOS of 80mm or so, you'll find out that the 76mm is slightly better than the US 75mm in this case.

[edited to correct spelling ]

[ November 04, 2002, 01:41 PM: Message edited by: Amedeo ]

[Mud]

Note that the penetration tables are versus "typical" enemies. Performance may vary given the different varieties of ammo... even if you hit. There's only room for one table, and there are no buttons that let you say "Suppose the opponent's armor is face-hardened" or "Suppose it has some armor bolted on" or "Suppose it's spaced armor".

(M3 isn't a Sherman; it's a halftrack, or the designation of the 75mm gun /on/ the earlier M4 Shermans. Do you mean the M4A3(75), or the rather superior gun on the M4A3(76)?)

[Guest Mike]

I thought the Russians used APC and APHE ammo??

But part of it is possibly also their use of blunt nosed projectiles - much better than sharp nosed ones vs sloped armour, but much worse against vertical armour.

[Silvio Manuel]

Originally posted by Mud:

Note that the penetration tables are versus "typical" enemies. Performance may vary given the different varieties of ammo... even if you hit. There's only room for one table, and there are no buttons that let you say "Suppose the opponent's armor is face-hardened" or "Suppose it has some armor bolted on" or "Suppose it's spaced armor".

Interesting... I had wondered what exactly the "vs. typical enemies" thing meant. Perhaps that's what explains the fact that even though Soviet AP ammo mostly switches over to the better kind in late '44, the penetration tables do not change. You might only see the real "change" in-game when targeting another tank and seeing "good" instead of "rare" or something like that.

[Warren Peace]

Yeah, I meant to say M4A3 (75).

This is interesting. So the APCBC ammo is better against vertical slabs, but the APBC is better against sloped armor? What about the "face-hardening"? Do all german tanks have this feature? Do any allied ones?

As an aside, I read in Lucas's Eastern Front that something like 30,000 Russian tanks and SP's were destroyed by Stugs. Certainly from CMBB is see how this might have occured! Still, I am surprised that the Sherman is superior to the T34 with respect to its weapon.

Warren

[Bastables]

Originally posted by Warren Peace:

Yeah, I meant to say M4A3 (75).

This is interesting. So the APCBC ammo is better against vertical slabs, but the APBC is better against sloped armor?

Warren

APCBC is better vs FH armour because it's the cap that is taking stress, therefore the shell/shot does not shatter. Russian ammo is so brittle through the war that it will consistently fail versus FH armour even with a cap. The ability for later Soviet AP shells to penetrate StuG armour has more to do with the late war StuGs switching form FH armour to RHA armour. Take a T34-85 versus a StuG G early or F/8 and be surprised by the StuGs ability to shrug off 85mm hits with partial penatrations and shot shatters.

[ November 04, 2002, 05:19 PM: Message edited by: Bastables ]

[John D Salt]

Originally posted by Amedeo:

The difference lies in the fact that the US 75mm has APCBC ammo while the 76mm gun has APBC ammo.

Since the StuG III has typically not-too-sloped face hardened armour plates, the 75mm APCBC has the advantage of the cap vs. FH plates, while the APBC shell cannot exploit its inherent better performance against sloped armour (on the contrary it's slightly worse than vanilla AP rounds vs. vertical plate).

[snips]

Eh?

I always thought that, other things being equal, capped shot performed better at high angles of impact and uncapped at near normal.

Of course, other things aren't equal here, because of the FH plate.

All the best,

John.

[rexford]

Originally posted by John D Salt:

</font><blockquote>quote:</font><hr />Originally posted by Amedeo:

The difference lies in the fact that the US 75mm has APCBC ammo while the 76mm gun has APBC ammo.

Since the StuG III has typically not-too-sloped face hardened armour plates, the 75mm APCBC has the advantage of the cap vs. FH plates, while the APBC shell cannot exploit its inherent better performance against sloped armour (on the contrary it's slightly worse than vanilla AP rounds vs. vertical plate).

[snips]

Eh?

I always thought that, other things being equal, capped shot performed better at high angles of impact and uncapped at near normal.

Of course, other things aren't equal here, because of the FH plate.

All the best,

John.</font>

[Tarquelne]

As near as I can tell the gun's have almost identical penetrations, so why should this be?

Which penetration charts are you comparing? Looking at CMBB's tables for June '43* guns don't have what I'd call "almost identical penetrations." At 1000m+ the figures actually seem to favor the 76. However, at 500m or less, what I'll call "CMBO ranges", the 75 gives better results. That'd go some way toward explaining it's success against StuGs in CMBO.

*M4A2 Sherman's 75, not the M4A3. AP ammo. I'm assuming they have the same gun and ammo.

FHA vrs. RHA: I'd like to see some indication of which (or "what") sort of armor a unit has. Maybe a code letter after the mm figure?

[ November 04, 2002, 10:34 PM: Message edited by: Tarqulene ]

[MikeyD]

I replayed "Chance Encounter CMBB" (the old CMBO demo scenario remade for CMBB) once fighting Stugs against T34-76's, and against after altering the game to field M4A4 Shermans.

My seat-of-the-pants opinion is that the game pretty much matches Rexford's assessment of the projectiles. 75mm was getting clean penetrations against the Stug's 80mm front armor while 76.2mm was getting partial penetrations or ricochets. On top of that Sherman's response time and first round accuracy seemed much much higher (advantage of the 3 man turret and stabilized gun?).

[ November 05, 2002, 01:27 PM: Message edited by: MikeyD ]

[Warren Peace]

One of the things that is interesting is the difference between straight AP and APCBC. Sherman's in 43 use AP and this is unable to penetrate STUGIIIG armor (at least at 700 meters), However, the same tank in June 1944 now uses APCBC and can penetrate (although in gunnery ranges the stug still wins at least 2:1). In the tables at 100m 0 degrees the AP ammo penetrates 113mm while the APCBC only penetrates 90. At 1000m the numbers are 74 for AP and 75 for APCBC. At 2000m the numbers are 41 for AP but 61 for APCBC!

My conclusion is that AP ammo effectiveness drops down faster with range, but is better at penetrating at short distances. Would AP defeat a stug at very close range better then APCBC? I'll try when I get home.

[rexford]

Sherman 75mm AP round outpenetrates APCBC against rolled homogeneous armor, and is not so good against face-hardened. Difference is the caps, and uncapped AP loses velocity much faster than APCBC.

75mm AP

Homogen. armor: 109mm at 100m and 84mm at 750m

Face-Hard armor:91mm at 100m and 66mm at 750m

75mm APCBC

Homogen. armor: 88mm at 100m and 77mm at 750m

Face-Hard armor: 102mm at 100m and 90mm at 750m

75mm APCBC does to face-hard what 75mm AP does to homogeneous armor.

I think CMBB only lists the homogeneous penetration for a weapon, which might be misleading people.

Americans found that uncapped M72 AP for Sherman 75mm gun was shattering ALOT. I believe that Russians found that Sherman 75mm ammo was pretty good against Tiger side armor at close to medium range. 75mm AP looks like it would eat up Tigers frontally and from side at close and medium range, but it shatters and has other problems.