Yes and no. Some box mag systems are drop in kits where others require some in-letting of your stock. For instance, Accurate Action sells the Kwik Klip box mag kit for long and short actions, this kit is a drop-in, the drawback from what I've seen is that their mags are single stacked making their 10 round mags long and difficult to deal with on the bench. Whereas Badger Ordnance sells a box mag kit that requires in-letting, this kit however is also one of the best on the market and their mags are double stacked. Double stacking makes the mags much shorter and easier to deal with with regards to bench shooting. The Badger Ordnance kit will also allow the use of Accuracy International mags.