To be “That Guy”: It really is not realistic or practical in the slightest.
The chainsaw bayonet would be very heavy (hence every one looking like The Rock on even more steroids). And there is a reason that many (most?) modern militaries don’t even issue bayonets anymore in favor of dedicated knives that are more for utility than anything else. Because… just watch the clip from Its Always Sunny of Mac trying to get in close to Charlie with a sword. Guns are actually still very useful close up and the main reason behind the bayonet was that you would be in close enough quarters to not be able to reload (since it took 20-60 seconds). Bayonets are especially “stupid” in modern combat because that means you already have the barrel pointed at the person you want to murder…
A chainsaw bayonet is just REALLY heavy and the gears would almost always be better off with a larger magazine. Because you REALLY don’t want to be in melee range with the big mega bug people anyway. Assuming there was something special about their hide/chitin, a 40k-style chainsword would probably be a better choice. They get in close, you quickly flick the safety and let your gun hang while you get your Ciaphas Cain on.
Assuming the bayonet form factor were actually required/useful and the goal were practicality? Something like the snap off utility knife swords from Attack on Titan would actually be really cool.
To be “That Guy”: It really is not realistic or practical in the slightest.
The chainsaw bayonet would be very heavy (hence every one looking like The Rock on even more steroids). And there is a reason that many (most?) modern militaries don’t even issue bayonets anymore in favor of dedicated knives that are more for utility than anything else. Because… just watch the clip from Its Always Sunny of Mac trying to get in close to Charlie with a sword. Guns are actually still very useful close up and the main reason behind the bayonet was that you would be in close enough quarters to not be able to reload (since it took 20-60 seconds). Bayonets are especially “stupid” in modern combat because that means you already have the barrel pointed at the person you want to murder…
A chainsaw bayonet is just REALLY heavy and the gears would almost always be better off with a larger magazine. Because you REALLY don’t want to be in melee range with the big mega bug people anyway. Assuming there was something special about their hide/chitin, a 40k-style chainsword would probably be a better choice. They get in close, you quickly flick the safety and let your gun hang while you get your Ciaphas Cain on.
Assuming the bayonet form factor were actually required/useful and the goal were practicality? Something like the snap off utility knife swords from Attack on Titan would actually be really cool.
Obviously I’m not being literal lol it’s an automatic rifle with a chainsaw on the end. It gives off exhaust fumes and requires gas.
My point is how it feels and appears. It’s just a very convincing weapon at face value. Most sci-fi weapons will not hold up to scrutiny.