The marksman carbine is a semi-automatic, medium-power rifle with a 20-round magazine. Mounted with an enhanced-zoom scope that shares the same mil-dot reticle as the anti-materiel rifle and sniper rifle, but its barrel and magazine appear to have a stainless steel coating, it is highly accurate and deadly at long range with a Gunsskill of 100. Additionally, it has a very low Action Point cost of 14, lower than most pistols as well as being the lowest out of any rifle in the game.
Hidden Valley bunker - can be purchased from Torres, may require the Courier to complete some BoS quests to allow higher tier of equipment to be available to purchase.
Carried by Legionary assassins once the player character reaches a high-enough level.
One of them can be found near Securitron de-construction plant on the pipe to the east from the main entrance. Just follow the pipe until finding a spot which the player character can jump up onto the pipe from.
Carried by Marked Men if the player character reaches high levels, if the player character level is 40 or above, they will use armor piercing ammo against the Courier.
The masked NCR troopers in the Hoover Dam visitor center may carry them.
According to J.E. Sawyer, the marksman carbine is loosely based around "paratrooper-oriented marksman rifles" and are present due to New Vegas' proximity to Nellis AFB.[2]
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Marksman carbine with the extended magazine modification that was cut from the game.
