.223 ar wanting to convert it to 6.5 grendel

[Swampfox]

I personally would just build a complete upper, and there is several reasons for this. 1 the enjoyment of building a upper, 2 the pride of doing it yourself (especially for your daughter), and 3 you know what parts was used and it was done correctly. With sales of Black Friday and cyber Monday being here shortly you could save money on a build. Aero Precision or Anderson upper receiver, RTB low mass Bolt Carrier+ parts, CH, Group buy barrel and bolt, spikes gas tube, adjustable gas block, handguard, and VG6 6.5 muzzle break. Tools needed armors wrench, upper receiver block, TQ wrench, roll pin punch, and locttite. Also if you wanted to you could just swap your CH back and forth, and to be honest you could do the same with your Bolt carrier, and just add the group buy bolt when shooting the Grendel.