I have a 20 ga Grade 5 that I use for pheasanting hunting. Bought it many years ago off a fella who just like to look at and never fired it. Beautiful gun, however the first fall I used it, it was the nicest single shot 20 ga in existance. Dam thing would not cycle shells to save its soul. The bolt stuck shut as a permanently peened in place pin in the bolt assembly wasn't so permanently peened over which came loose and jammed the bolt in a closed position. All this happened at Pelee Island during a pheasant hunt. Come dam close to throwing the gun in Lake Erie. I sent it back to Browning in Montreal at the time with a letter expressing grave disappointment and the guns issues. I also stated I never wanted to see the gun again if they couldn't make it function 100%. Seven months later Can Par shows up at my door with the gun. Note inside stating it was repaired free of charge for "customer good will", also a list of all the brands of ammo they put through it.
No mention of what exactly the issue was but it has worked flawlessly since. A great pheasant gun as long as it's working properly, knock on wood I hope it stays that way. This one probably was an isolated case of leaving the factory improperly adjusted.