No, that doesn't sound right at all.
The mag size would be totally unrealistic; which is a pet peeve for people like me. 30 rounds of .45ACP is the standard for the Mac-10, 32 for 9x19mm Parabellum.
Depending on the manufacturer, it is 30. There are plenty of 10 and 20 round magazines as well. That's like saying an M4/M16 should only have 30 rounds. There are 20 round box mags.
http://www.ammunitionstore.com/products/MAC10-Magazine-20-Round-9mm-National-Magazine-Mfg.html
Who knows? Maybe the trader only had 20 round magazines. There's no reason to say the M4 MUST have 30 bullets when you can get a 20 round box magazine. I mean, look at the MP7. How'd you fit 40 bullets in the 20 round base mag at Level 5?
Then it will be as powerfull as a 9mm...no.
I think it is as powerfull as a handcannon but with accuracy of the medicgun then it don't must have less power than yet.
As C_Gibby i think about a dual welding weapon because the caracetre take it only with one hand and it isn't enough powerfull to be alone.
You earn firebug damage only using the mac 10 with this perk and you must let it on fire to level up the perk then it don't must be balance to be less powerfull.
The only way to level up the perk is to ironically not shoot them in the head. Meaning you are rewarded in perk leveling for NOT having good aim.
Sounds like someone came up with those just so he can dual-wield it. Personally, I like it the way it is. Unperked, it isn't all that useful to other kits, but invaluable to us Firebugs.
It would be less overpowered if they cost more or were weaker, because as it stands, you can just stockpile 10 of them, go crazy with full auto, and grab another. The gun itself makes Firebugs have a lightweight crowd control gun that puts the AK-47 to shame.
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The biggest issue I have with it is that it is inherently not a Firebug-leveling friendly gun. It is easier to level with the flamethrower in crowd control simply because you can only shoot the front targets to get fireproc. If you get a headshot, no XP for you. It then becomes a "should I slaughter them, or should I farm fire damage from them" argument. The point of lowering the capacity is to make it more appropriate to dual wield. I'm sure people would have a field day with 94 ammo Dual Mac-10s. The damage decrease is offset by the increased rate of fire, and also allows firebugs to get more out of their fire proc, which I assume would be the purpose of this weapon: to level the firebug.
Dual wielding makes it more practical for a Firebug to effectively crowd control with a spammable, or effectively snipe with a single.
Also consider that after the first wave you can easily buy 3 or 4 of these things, you could stock an entire team of low-level basically with one high-level Firebug, and then farm Waves 1-6 with crazy Procs.
In other words, this gun is basically the overpowered replacement to the M14 for Firebugs. High ammo capacity, low cost, super-high accuracy in semi-fire, crowd control, fire procs, and allows you to main a crossbow as backup (the only other class that gets a decent primary and XBow would be Sharp itself)...