7.62 what? If you mean NATO,7.62x51,its a whole different rifle.If you mean 7.62x39....I have no experience,but the case taper,mag curve factor may,not for sure,but may,have different feed characteristics.
You might 1)Sell or trade the 7.62 or2)buy an SKS,AK-47,Saiga,Ruger mini-30,etc