Marksmen is a Paid DLC for Arma 3 that was announced on 1st May 2014. Release date is TBD.

Arma 3 Marksmen main features, in a short list:

ASP-1 Kir - NATO designated marksmen rifle with built in supressor that fires 12.7x54mm ammunition.
Mk-I EMR - NATO DMR that fires 7.62x51 NATO ammunition.
MAR-10 - NATO DMR that fires .338 Lapua Magnum ammunition.
CYRUS - CSAT DMR that fires 9.3x64mm ammunition - Made in Chernarus.
SPMG - NATO belt fed light machine gun that fires .338 Norma Magnum ammunition.
NAVID - CSAT belt fed LMG that fires 9.6x64mm ammunition.
Mk14 - AAF DMR that fires 7.62x51mm ammunition.

The supporting content is provided free of charge alongside the Marksmen DLC. Some of the content may still require ownership of the DLC.

External Links

Arma 3 Marksmen