I've NEVER sent a weapon (rifle shotgun nor pistol) back to the mfg. In over 40 years, the factory has done little to follow what the buying public wants to do and more for the liberal gun control zealots. Think about the safetys on the pistols now-a-days.
I reload ALL my ammo and when I do buy factory stuff, it's just to get the brass mostly.
In my .300 win mag, a factory load is good out to about 400 yards realistically, and I can reload rounds that I can easily place where I want out to about 800-1000 yds. That in itself says something about factory loads. They are a compromise for the averag shooter and average gun. I custom load my stuff for the gun, specifcially... so my ammo is better than factory in that regard.
The warranty thing is to cover their butt from people wanting to insanly load up to and beyond the max allowable charge thinking faster & hotter is more accurate and better, which anyone who loads their own will agree is just stupid.
If you drop a hotter & faster load from a friend who has been able to shoot it in their gun into yours it might just be TOO hot and TOO fast and the pressures might just be beyond what your gun will take and any damage is on you.
I don't worry about reloaded stuff because I ONLY shoot my own stuff in my own guns but you might want to think long and hard about your decision. If you're the kind of person who NEEDS the factory warranty, then maybe you should only shoot factory ammo in order to be safe. After all, being safe is better than being dumb.