Bought a mini 30 with plastic stick-bought a wood stock replacement-wood stock had holes on each side for a stock brace so I ordered one and installed it. Now receiver and trigger assembly fits much tighter but goes in-but magazines will not go in
Sure the wood stock/brace you bought was for a Mini 30? The inletting on the Mini 14 stock is almost the same but I've heard of issues fully seating the magazine well/magazines in the well when the 14 stock is used on the 30.
You likely don't have the correct brace for it. Also a good chance that you have a .223 stock. Numrich ( Gun Parts corp)Corp, occasionally gets the correct mini 30 braces in. Don't order a mini 14 brace. They are not interchangeable.