the Anti Material Rifle is for sale at Gun Runners and the Gobi Scout Rifle, if it's the one I'm thinking of is at Snipers Shack near Cottonwood Cove in a "Very Hard" locked footlocker..Do you have the Dead Money DLC?? If you do the Holorifle is my weapon
of choice.. it's long rage and if you fire from the hip it's almost like a shotgun..it uses microfusion cells til... I'm level 45 with 100 in Energy Weapons and I took down the Legendary Deathclaw in 3 shots with it!!
never found the MIRV if there is one in this?? Not my kind of weapon at all! I'd recommend doing Dead Money at a high level..I was level 19/20 I think and struggled in some places....definitely keep hold of the Holorifle though and try to upgrade and as
much as possible
For the early part of the game I suggest This Gun, if you can steal it from the story in Novac (or is it Movac?). I can't remember the name for certain but the gun itself is a futuristic revolver with pretty decent stats. It's in the shop in the big dinosaur,
though I cannot remember the name of the town. You can buy it or steal it by going into the back room of the store.