Yes, but don't use the original bolt face which came with the bolt and carrier if it's been used - get a brand new one.
well the standard ar-15 is a colt. but now these days the most poopular are generally either DPMS or Bushmaster. the best of the Best is Barret and LWRC.
Leitner-Wise Rifle Company, Inc. or Land Warfare Resources Corporation depending on the time period involved.
1- M4A1 2- M16 3- M4 4- HK 416 5- Hk 36C 6- Hk 36k 7- AK47 8- HK G3 9- LWRC PSD 10- Tavor Assault rifle 11- Magpul Masada 12- AR-10 13- M-110 Sniper Rifle 14- M249 SAW PARA 15- 50 Beowulf 16- XM8 Assault Rifle 17- 6.5 Grendel Alexander Arms 18- Barrett .50 cal sniper 19- Ak 74 20- M16A1 21- Dragunov (SVD) 22- Beretta LTLX7000
No, the reason for this is because the marines need a bullet that can be used for all ranges. However, if you are in close corters or you need to stop a vehicle, then i would say the Beowulf 50 caliber carbine cartridge would do the trick. But the M4A1 must be used for the Marines. PS: i think that at least one person in the Platoon should have one.