BudsGunShop.com - FMJ for 9mm.

Hi Mike, no sir, FMJ will not harm the barrel. FMJ is what you want for range/target practice.
Stay safe & have a great day!

Hi Mike and welcome. No Sir. Copper Jacketed FMJ will not harm the hardened Steel Feed ramp or the barrel whatsoever. Cheers, stay safe and enjoy!

Absolutely Not.
No, full metal jacket (FMJ) bullets are generally considered safe for your firearm's barrel and do not cause excessive wear or damage.
Here's why:
Purpose of the Jacket:
The jacket around a lead-core bullet in FMJ ammunition allows for higher pressure and temperature during firing, while preventing the soft lead from melting or wearing off inside the barrel.
Reduced Lead Deposits:
The jacket, typically made of copper or a similar metal, helps to reduce or prevent lead deposits in the barrel, which can occur with unjacketed bullets.