... so I would like to know that if i continue to shoot will it hurt anything? Wheres should be the cut off point? I currently do 3 shots and let it cool for 5-10 minutes.
I personally have never had the distinction of actually shooting out a barrel completely. Though I have shot enough to make for throat errosion/wear.
Your practice of 3 shots and let cool method is a good one.
Keep it up and you will have a good condition barrel for a long while. These Handi barrels are of good quality, and from my stand point the more I shoot them the better broken in they become and the better accuracy potiential they release.
Just keep up Regular and Proper cleaning.
Shoot and Enjoy your rifle, it certainly sounds like you do.
-Aaron