A chassis (or bottom metal) does not determine whether you can use AR Magazines with a bolt action rifle. AR Magazines do not sit high enough against the bottom of bolt actions to make it feed properly.
There are only a few Bolt Action rifle platforms that allow the use of AR magazines, and that is the Mossberg MVP and a specific model of the Ruger American.
So our chassis for the Mossberg MVP is made to use AR magazines exclusively. For the Ruger American, you need the specific Ruger American compatible rifle and choose our chassis compatible with the AR magazines.
All our other chassis use standard external box magazines.