Can I shoot 5.45x36 in a 5.56 Rifle?

So I bought a rifle back in October and bought some range rounds and some home defense rounds. I got 5.56 for the range and 20 rounds of Hornady black 5.45x36. Now I’m in the army but when I mentioned the ammo I had gotten to a buddy of mine he said I’d destroy my receiver if I shot the 5.45 through my rifle. I’m half doubting him and half too scared to test it in case I do destroy my receiver in the process of figuring out if I can shoot the ammo through my rifle. If anyone can help give some advice for me it would be greatly appreciated.

Edit: so what I’m getting at is now I have 20 rounds of 5.45x39 tracer rounds for the laughs now….cool Also I do not intend to get ride of the ammo will just have to buy a rifle that is able to shoot it, most likely a GAR71 if anything.