Regardless, that model sure is pretty.
Who knows why the Chicoms do what they do.
I just know the darn thing is rare and from a collectors standpoint I should have bought it
You just pull the action from the stock and pull the fixed magazine completely out. Replace the action in the stock minus the magazine and the after market mags go right in the hole in the stock pretty as you please and lock in place with the original magazine latch. I run 6 sks’s for ranch guns and they all have 30 rd magazines.