Im trying to start the mission "Dealing with Conteras" to obtain the "This Machine" rifle, but I dont know how to start the quest. I found Conteras at McCarran, but when i tried to get the mission from him, he sent me to Isaac at Gun Runners to help him get 100 scrap metal. Do I have to finish this task for him to give me the quest? Or is there someone else at McCarran who gives it?

I didnt have to do anything with scrap metal.. but yeah, it is Conteras who starts the quest.. just keep doing his jobs for him.. the quest is an unmarked one.. so it never shows up in your quest log..

fwiw .. if you get a sniper rifle.. its the same (basically) damage as This machine.. but no scope.. Im not real impressed with it

All I did was hack his computer, look at the incriminating files and report him to lieutenant boyd who gave me the gun as a reward.

That was my original plan, but my science wasnt high enough... even with a skill magazine. I guess ill just finish this stupid scrap metal thing, i have most of it anyways.