Hard to judge what is happening when we can't see it (BIG HINT THERE, BUB)
However, if you are trying to reinstall the factory fixed mag, the rifle need to have the action taken out of the stock first.
I have known ONE person that has changed an SKS to detachable mags, and says that it works well. But I play poker with him, and he lies there too.
The SKS did not have, nor need a feed ramp. Slight bevel of the mouth of the camber on the lower edge.