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human
[WH40k] How powerful are lasguns?

So, let’s put this first, lasguns have a noticeable level of effectiveness in battle, they can put a hole clean through and ork, penetrate (I think) space marine armor at the weak spots (joints, elbows, neck etc.) and can put a hole in a tyranid as well, albeit you have to turn the said ork/tyranid into Swiss cheese before it dies. And you could just say, “well, why not just get space marine and use a bolter, well, most guardsmen and civilians don’t see a space marine in their lifetime, and they aren’t at a whole lot of battles, especially if the imperial guard is capable of winning the battle by itself, to add to this, the imperial guard is very capable of winning battle without the help of space marines (its happened many times before) so back to the question. What I want to know, is how powerful and effective will a lasgun be in efficiently killing orks and tyranids?
gpt
Very effective. The lasgun is one of the greatest weapons of war in scifi history. You can reload it from anything that generates heat, leave it outside in the sun for a new clip, holds a shit ton of shots, 100% accuracy, functions in just about any environment and so simple to use a feudal farmer can wrap their heads around it. 

When dealing with big bads a single lasgun wont do shit. A few hundred lasguns all firing in unison on a target will fuck up just about anything without shields. 

Its a perfect anti air weapon as well. The rounds travel at the speed of light and have zero bullet drop, which is one of the reasons maintain air superiority against humans is hard. As soon as you get close to the battlefield a thousand flashlights with the stopping power of a 50 cal round are hitting you instantly from every location. 

Most orks go down with a shot or two from a lasgun, once they start getting bigger you might need a handful of shots to drop an ork. 

Tyranids are similar, a single round stops most grunts and focused fire can deal with just about anything smaller than titans with shields.