Using gyro-stabilized CMGs

jrv

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This is a how-to, not a question.

In "Centurions Reverse!" the BCFK have four Centurion IIIs. If you read the vehicle notes you will find they are gyro-stabilized always, despite not having a "G" printed on the counter. Gyro-stabilizers help the main gun, and they also help the CMG. The gyro-stabilizers reduce the TH DRM for moving for the MA and allow the MA to gain & retain acquisition for bounding (first) & Motion fire. Once a target is acquired, it can be fired on by the CMG without halving for bounding (first) or Motion fire. During its MPh a gyro-stabilized CMG is still halved for non-stopped fire.

If a Centurion comes across an unconcealed, unacquired CPVA squad in open ground (there's an awful lot of open ground in "Centurions Reverse!") during its MPh it can move adjacent & stop. It can now fire its MA (perhaps using AP, because the Centurions have limited HE). It will probably need a six to hit (+2 case B, +1 case C, +1 BU). Whether it hits or not, the target is now acquired. The Centurion fires it four FP CMG at eight FP (point blank range, not halved for bounding first fire) flat. The Centurion then starts up again because it does not want to be stopped during the Chinese turn (the Chinese don't take PAATCs, and they have Assault Engineers in this scenario).

The obvious alternative is to perform an OVR, but this isn't quite as good a choice as it might seem. A Centurion performs an OVR at ten FP, which isn't much different than the eight FP for just firing the MG. It would receive the -1 DRM for Open Ground, but the BFF approach makes two attacks, MA & CMG. The MP cost is only two MP (stop & start) for BFF while its four MP for OVR. The Centurions only have twelve MP, so savings like that make a big difference. Lastly using OVR gives the CVPA unit a possible CC-RF attack (or thrown DC) because any attack may just step-reduce (or not affect) the defender. A BFF attack does not give a CC-RF opportunity, and any thrown DC will be through the front VCA. Note that using gyro-stabilized BFF is perhaps even better if the Chinese are in the light woods because the Centurion also avoids a Bog Check.

If the BCFK player uses his Centurions in groups, other Centurions can repeat this, and after a bit of battering the CVPA squad will no longer be a threat. The Centurions in "Centurions Reverse!" are going to be a dangerous threat to CPVA troops when they use BFF gyro-stabilized fire during their MPh.

JR
 

bendizoid

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Is it possible that the cmg is not halved in the overrun calculation? It would then overrun with 16.
 

jrv

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Is it possible that the cmg is not halved in the overrun calculation? It would then overrun with 16.
Per D7.11 the OVR FP is halved for BFF. If you start the MPh without acquisition you would have to fire to gain it. Once you do that you are marked with a BFF counter, and as importantly you can't use the secondary armament outside that hex. So if you are gaining the acquisition that MPh you can't use the CMG a subsequent OVR, and probably can't perform an OVR at all.

I don't know what happens if the MA already has the acquisition from a previous turn. As written I think the CMG FP is not halved if the MA already has acquisition from a previous turn, but I don't know what the PerrySez would be.

JR
 

jrv

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Ma keeps acquisition, it’s gyro.
It would have to have it in order to keep it. My example in the first post started without acquisition. You bring up an interesting point about what would happen if you start with acquisition.

JR
 

bendizoid

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It would have to have it in order to keep it. My example in the first post started without acquisition. You bring up an interesting point about what would happen if you start with acquisition.

JR
Yes it does because now you could ‘bounding fire’ into its own hex at triple fire, if you had to. The rule seems a little backward because I thought they used the coaxile to range in first, before the MA.
 
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Magpie

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Why would you stop adjacent to the enemy unit? Wouldn't you just fire the MA whilst in motion, gain acquisition and then shoot the CMG?

Would D7.11 be overridden by D11.13 ?

" So if you are gaining the acquisition that MPh you can't use the CMG a subsequent OVR, and probably can't perform an OVR at all. " by 7.1 you can't overrun at all if you already have a BFF counter

As an aside, do the rules give any indication as to why the Centurion has limited HE?
 
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klasmalmstrom

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As an aside, do the rules give any indication as to why the Centurion has limited HE?
UN Forces Vehicles Note 38:
"...After the experience fighting the Chinese at the Imjin River in April 1951, the Centurion Mk III was re-equipped with more HE ammunition and less APDS, as well as with searchlights and an AAMG (sometimes a .50-cal, although more often a .30-cal Browning). ..."
 

jrv

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Yes it does because now you could ‘bounding fire’ into its own hex at triple fire, if you had to. The rule seems a little backward because I thought they used the coaxile to range in first, before the MA.
The use of a ranging machine gun (or ranging rifle) was post-Korea I think. According to wikipedia it was introduced on the Centurion Mk 5 had a ranging rifle. I don't know that it was used in Korea. According to the article it was introduced in 1965.

JR
 

jrv

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Why would you stop adjacent to the enemy unit? Wouldn't you just fire the MA whilst in motion, gain acquisition and then OVR ?

" So if you are gaining the acquisition that MPh you can't use the CMG a subsequent OVR, and probably can't perform an OVR at all. " - can you explain that further if you don't mind?
When you fire the MA in a hex you must use the MGs in that hex, per D3.51. They are not available for the OVR in the next hex. Most likely you are marked with a first fire marker, and then you can't OVR at all.

JR
 

klasmalmstrom

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...The obvious alternative is to perform an OVR, but this isn't quite as cost is only two MP (stop & start) for BFF while its four MP for OVR. The Centurions only have twelve MP, so savings like that make a big difference. Lastly using OVR gives the CVPA unit a possible CC-RF attack (or thrown DC) because any attack may just step-reduce (or not affect) the defender...
Can the CPVA Throw a DC into its own Location (like Japanese)?
 

Magpie

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UN Forces Vehicles Note 38:
"...After the experience fighting the Chinese at the Imjin River in April 1951, the Centurion Mk III was re-equipped with more HE ammunition and less APDS, as well as with searchlights and an AAMG (sometimes a .50-cal, although more often a .30-cal Browning). ..."
OK, seems a little odd that such a thing doesn't apply to other vehicles that have similar ammunition loads. eg the Cent carries 65 rounds and have infinite D and HE8 but the M4A3(76) 's carry 71 rounds and infinite A but no restriction on HE.
 

Magpie

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The rule seems a little backward because I thought they used the coaxile to range in first, before the MA.
They could use the CMG for ranging but they weren't compelled to.

Ranging with the CMG applies to any tank, it just wasn't often done due to the time required, giving away one's position and given the CMG generally wasn't ballistically matched to the MA it wasn't super useful. By Korea too, CMG's which were usually a 30cal , were starting to not have sufficient range to match the MA.
 

jrv

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Can the CPVA Throw a DC into its own Location (like Japanese)?
Not in general. They can throw against a bypass AFV, as can everyone else. Only the Japanese can throw against a non-bypass vehicle target in their own hex.

JR
 

jrv

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By Korea too, CMG's which were usually a 30cal , were starting to not have sufficient range to match the MA.
As best I know the ranging MG was added to the Centurion with the 105mm gun. It was a .50 caliber weapon. I haven't been able to pin down dates, but after Korea seems likely.

JR
 

Magpie

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As best I know the ranging MG was added to the Centurion with the 105mm gun. It was a .50 caliber weapon. I haven't been able to pin down dates, but after Korea seems likely.

JR

Yes the 50cal was the ranging MG, due mainly as I said to the fact that the 50 could be ballistically matched to the MA and had sufficient range to be useful. Still not 100% though as you had to be able to see the rounds striking the target which wasn't so easy at long ranges. Best you'd get is about 1 mile / 1600m

The CMG was still a 30cal though, the 50 was only for ranging not shooting.
They were introduced around 1966
 
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