I recently purchased a Type 56 that accepts AK mags. It came with one short 5 round mag. The mag looks identical to the mags I am using with my SKS-D. It functions well during shooting. Here's the problem. The mags that I am using in my SKS-D will not lock into the Type 56. It appears if the lips on the mag for the Type 56 are about 5 mm shorter than the rest of my mags and this is preventing my other mags from locking in place. This mag does however function in my SKS-D with no problems. My question is has anyone else had this problem? Do I have to modify my current mags to fit or are there slightly different mags available for this rifle.
The mag on the left is my SKS-D mag and the one on the right with the shorter mag lips is the one that came with the Type 56

The mag on the left is my SKS-D mag and the one on the right with the shorter mag lips is the one that came with the Type 56