It's honestly one of my favorite loads. I don't find it to be the best to break in a gun, but if you've already got 500 rds through I would think you'd be ok. If you had a chronograph that'd be a good way to see if its really underpowered.
Know the status of your weapon
Keep your muzzle oriented so that no one will be hurt if the firearm discharges
Keep your finger off the trigger until you have an adequate sight picture
Maintain situational awareness