The title says it all really, I'm working on a rifle and I just can't figure out what's causing it's outragous recoil (it causes the actor to fly away at a high velocity), mainly because I don't know what for sure what variables determine the recoil of the gun
I've guessed that the round used's mass is one of them, but I'm not so sure

The round the gun fires is probably very heavy.

Projectile's mass, round velocity and quantity of projectiles all determine the recoil.

If you want to by pass recoil, there are several ways to do it.
One can be found on the Coalition sniper and heavy sniper. It fires an emitter that fires the actual rounds plus also some effect stuff. You can study that in coalition.rte.

The other is making a TDExplosive that does the same as the emitter trick.
Make the "TDE" object detonate immidiatly as it leaves the barrel and the momentum of the particles takes care of the rest.

newtons 3rd law,

but isn't there a variable to destroy recoil, no matter what?
fireginorethis = 1,
or
emissionignorethis = 1
or something like that?

Those variables control whether or not an emission or round particle collides with the parent; nothing to do with recoil.
There's no recoil variable. A RecoilFactor would be nice though...

On the subject of recoil, how can you get enemies to be pushed backwards?

Kinetic particle spread or lua.

it's 20, I don't think it does much of a difference, but perhaps it's the velocity, as I know now thanks to numgun

It's determined by amount of rounds, mass of each round and fire velocity. So a 20 mass particle will produce insane recoil even if only fired at 20 velocity

20 is very, very heavy.
If you don't want to get complicated, use 2.

I know this is just adding a question on to a question but,
what determines the zoom length/radius (how far away you can aim) of a sniper rifile? Or of any gun for that matter.

The wiki is a lot more helpful than you think, like I told this guy.

Oh wow, I can't believe I missed that. Thanks

That's 20 packs of sugar you fire with every shot. I dunno about you, but I would probably fall backwards.

Heh, I'm too used to screwing around with actors. An actor with 20 in mass is like nothing, so I forgot that I was in fact making a gun that would fire a tight spread of 5 rounds at a high rate of fire, meaning that the recoil would be horrendrous if every round weighed that much
Anyways, noticed that one myself, and I'm quite happy with the gun now, as I managed to preserve it's firepower.