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The big problem with not only the BPS but ANY pump shotgun is the NUT BEHIND THE BUTT PLATE. In other words, Operator error. People tend to get excited and short stroke the pump gun, thus ending up with a shell or an empty case in the chamber, and the second one jammed behind it on the lifter. Of course, it is ALWAYS the fault of the shotgun and not of the person who did not operate it properly by pulling the fore end back fully to cycle the action.
I have two BPS shotguns that I use. A short field gun I bought back in the 80s with the 22 inch barrel and straight English style butt stock, and a higher grade BPS that had two barrels with it and some fantastic wood on it. Never had a jam with either of them for almost 30 years of use. I had a friend who consistently jammed his 870 Remington, even though he was aware of what he was doing. He just got too excited when he cycled the action when the shooting action was hot and heavy. He just short stroked it and it was not the gun's fault. I finally took it and drilled two holes in the lifter, about two inches apart, then used a Dremel to make a slot between the holes. That way, when he ended up with a shell jammed in the action, he could take a knife, insert it into the slot, and push the offending shell back into the magazine. Saved having to disassemble the trigger group each time.
The biggest thing with any shotgun is FIT. This is where it pays to handle a gun, especially in a gun shop or store. There are minor differences in guns, even in the same models. You could buy two models of the same shotgun in a store and they may or may not shoot the same for your build and shooting style. What to do when looking at a prospective purchase is to have the gun in your hands, about waist level. Then pick out an object, say a picture on the wall, face it, close your eyes, and raise the shotgun to a shooting position. Your eye should be aligned with the barrel, and the muzzle somewhere near the object you selected. The important thing is FIT as a Shotgun is POINTED and not deliberately AIMED like a rifle is. Your eye must be aligned with the barrel or rib on the shotgun.
Another big mistake people make is to buy a shotgun in the summer, when they are in light clothes. Then, they go afield in the fall in heavier clothes or sit in a duck blind with long underwear, heavy shirt and parks. This can change your shooting dramatically.
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