500 rounds of 55gr 5.56 Winchester for other ammo or firearms

Have 500 rounds(in 20rnd brown box) of Winchester 5.56 55gr.
Looking for Frontier 223 68gr ammo or similar. Looking to try out some different weight rounds.

Also interested in a browning Auto 5, non engraved receiver(will add cash), gsg16-9", winchester 12g  97

OR $420 cash

thanks