This is an ammo question. 223 Ammo is pretty difficult to get here in my contry (Netherlands) and the only thing available at reasonable level is S&B .223 FMJ steel jacket with thin tombac walsed arount it (0.04 mm S&B has replied to my question) S&B as well as Bushmaster told be these rounds do NOT cause extra barrel/bore wear since the tombac layer would be thick enough to prevent the steel contacting the bore. So, I should feel comfortable. Nevertheless I'm not, recently I talked to 2 different rifle and ammo retailers both telling me they wouldn't sell S&B for that specific reason.
Either I would like to feel comfortable using S&B or just reject it based on solid arguments.
Thanks, leonard

Feel comfortable using it.  It works fine, and pretty accurate in my gun.

It won't fragment though, due to steel.

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