Originally Posted By: Orry
Originally Posted By: Riprap
13.5 LOP to a checked butt.


Pretty tough to hollow out a stock with a checkered butt.


Not sure how "tough" it is, but 21s do not have through bolts. Nevertheless, if you look carefully you'll notice the outline of the plug that will be found on every M21 checkered butt. 21 buttstocks are indeed hollowed out to varying degrees.

I don't know if the plastic stock sidelock versions I've recently read about are done up this way.

Sam