I have a sav eg 300 sav. Can I re bore this to 358 win? Will there be feed issues?

The receiver internals of most EGs cannot be modified work with a .358 size cartridge. If you are fortunate enough to have an EG with a serial no. Over 900000 it can be done.

As Jaaack stated, the earlier 99's will not accomodate the larger cases, and it will be a much more realistic conversion if You start with a 99 originally chambered in .308