Originally Posted By: ninepointer
L. Brown,

Thanks for you excellent explanation above. Sadly I've seen people put cheap promo shells into short chambers with the mistaken belief that they are low pressure loads.


While "promo" loads are typically light in shot charge, that does not mean that they are light in terms of either pressure or velocity. They are made with enough "punch" so that even dirty autoloaders will function, which means they're not really "light" at all. Thinking they're fine in short-chambered guns is indeed a mistake. I can load up 1 1/8 oz 12ga field loads which, although they have a heavier shot charge, will be lighter in terms of both pressure (down close to 7,000 psi, in the specific load I use) and velocity than your typical cheapo big box store load.