You must be 21 years or older to order I purchased 5000 Cheddite primers. He said nope, they wont increase the pocket size at all. Primers 209 for sale are constantly and rigorously tested for consistency and sensitivity at temperatures and conditions far beyond the range of normal usage. Due to Now that BPI has been selling the RIO unprimed hulls Ive been using these to prime those hulls with great success. To improve ballistic performances with most available powders, Cheddite has developed its dependable and powerful Clerinox primer (US type). I do use an o/u, so maybe different in a semi. Service. buy 209 primers at discount prices 100% safe delivey order from the best 209 primers suppliers today, which can be used under all conditions, are non-corrosive. selling ammunition, reloading supplies and accessories. Happy just to be able to keep shooting during these times. To improve ballistic performances with most available powders, Cheddite has developed its dependable and powerful Clerinox primer (US type). Cheddite 209 Shotshell Primers (Box of 1,000) - Precision Reloading Primers undergo rigorous testing to ensure consistency and sensitivity even in extremes of temperature and conditions. To improve ballistic performances with most available powders, CHEDDITE has developed its dependable and powerful CLERINOX primer. Cheddite load data | Shotgun Forum There's just not a whole lot of data for 2 3/4" loads using steel shot and Steel powder so it's hard to get a sense of how the powder behaves with various primers. I would be buying them from BPI but I have a local source which saves me the HazMat fee and we are all trying to save money. Ive shot well over 10,000 of these primers and havent had 1 problem. I found some Rio primers to put in the cheddite hulls after I shoot them.