I often see people use that gun on the Luchs despite the L/60 so much better in nearly every aspect:
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| Stat |3cm M.K|5cm KwK|
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|Penetration| 95/110| 67/130|
|Damage | 30 | 70 |
|RoF | 22,5 | 28,6 |
|DpM | 675 | 2002 |
|Aiming Time| 2,3 | 1,7 |
|Accuracy | 0,46 | 0,39 |
|Weight | 141 | 700 |
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As you can see the only stat which is better for the 3cm is the Weight which hardly makes any difference in my experience since the engine of the Luchs is rather strong.
Tazilon (who is writing scouting guides) suggests t use the 3cm but I don't understand why and he does not tell people why the 3cm is better. In my experience the burst of the 3cm is unspectacular (180). You can only kill a (very) low level arty with that burst if you are lucky whicle the L/60 spews out a whopping 500 damage while the 3cm reloads. If the target is far the 3cm is inaccurate while the L/60 is rather accurate and in close quarters you can easily circle any tank so the burst does not make a difference.
So all in all: what are the reasons for a Luchs player to use the 3cm?
Please note that I only load APCR ammo + HE ammo to maximize efficiency.