When we were issued 5904s there were the stories the aluminum frame guns wouldn't hold up to our 115 gr +P+ load. One of our range officers decided to shoot his 5904 with the +P+ round until it broke just to see how long it would last and if it would be a problem. At 50,000 rds he changed barrels because he'd shot the rifling out of the old one. He replaced springs but I don't recall round count. When he retired he had documented over 80,000 rds of +P+. He bought the same gun when he retired and continued shooting it.
That's roughly 1600 boxes of +P+. If you could find a deal on +P+ at $25 a box then he would have spent $40,000 on ammo thru that 1 gun.
Not to say that all aluminum frame 5904/5903 will go 80,000 rds. Had he been issued another gun it might not have gone a fraction without breaking. But at least one randomly issued 5904 did.

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183rd FBINA