the anti-materiel gun from the gun runners, that and the sniper perk and you're set
Get up high, either on top of the ridge or on a piece of mining equipment, preferably somewhere the Deathclaws can't reach you, although if you got there they probably can too. The higher and further away you are, the more confused their pathfinding is. I used a suppressed sniper rifle to get repeated criticals while hidden, but anything that deals a lot of damage will do. If you can't take them out quickly, try to cripple their legs to slow them down. Also, if you can kill one of the babies the deathclaw matriarch will frenzy and start attacking the other deathclaws, doing a lot of your work for you.
If you find the great khans outpost nearby then work your way down the ridge from there you should find a place along to the right where you can jump on a crane from the you can snipe all the deathclaws without them reaching you.
Archimedes II. Wait 24 hours. Repeat until killed all of 'em.
Not if you're playing on Very Hard. Riot shotgun + Shotgun Surgeon + And Stay Back.