I can't. No matter what I've tried, can't do it. I have Veronica and ED-E and the three of us are dead in seconds. I'll take those Legion guys any day!

The key is to attack them from long range. Don't try to fight them up close, they'll rip you to shreds in no time. Which means that Veronica isn't the best companion to use against them, try Boone or Raul. If you fire at them from far enough away, you'll have a chance to get in several shots before they finally close in on you. Plus getting in that initial sneak attack means that the first shot will do a fair amount of damage. Also, they have a DT of something like 10, IIRC, so using something that gets through that, like Armour Piercing ammo, will help a lot. Just last night I made it through Quarry Junction without to much of a problem. Only one of the Deathclaws managed to get close enough to do any damage to my team, which was ED-E and Raul, because I hadn't was very satisfying when the Alpha Male and Female dropped yards away from me. You got to love that All-American rifle.

Sniping and satchel mines are my favorite. You did not say what lvl you are? That will make a huge difference in what folks can suggest.