To my my knowledge, all pistol manufacturers have the disclaimer on hand loads. They kill the warrantee.
I worked for Glock GA for two years. So became friendly with some of the staff.
Officiating at an IPSC Ontario Canada match, at an indoor range near Orlando, one Sat. afternoon. An older shooter, he was 80. Fired the course, with quite the horrendous report from his Glock 17. He was new to the reloading game.
(I am 84, 80 isn't old!) He asked me could I adjust his rear night sight, I had the tool in my shooting bag. It was shooting to the left. Yes, 7" to the left, at 10 yds! I fired one shot, just like shooting a .44 Mag! Stripped it down, the slide was cracked at the bottom of the ejection port.
After cleaning up, locking up, off to Tim Hortons for coffee and doughnuts.
I know, real men go for beer! Canadians, what can I say.
He explained his reloading technique. He was using 115g hardball rounds with the max. charge of 700X (we bought that Dupont powder in Buffalow in 12 lb kegs) lasted a long time. We were supposed to declare it at customs?
I am an American now, more honest?
Back to his re-loading. When he used up his 115g bullets, he switched to lead cast 169g bullets he bought from a friend. No, he did not change the powder throw! I sent the slide back to Smyrna, with a note, asked that they send me a new slide. They had my credit card on file.
A funny phone call! And a new slide turned up, no note! No charge. Another buddy who had been loading for .45 & 9mm for years took our new loader under his wing. Done.