If you are shooting a Remington 700ML you will need a 209 primer conversion to reliably ignite pellets.The Remington conversion is often available on eBay for around $50 although it has been discontinued by Remington.Or you can purchase the Canadian made conversion from Cabelas for $42.It is easier to remove the fired primers from the Cabelas conversion than it is from the Remington conversion.The nipple on the Remington conversion uses a small circular spring that can be easily lost if you are not careful removing fired primers.Without it the primers canback out enough to cause a misfire.I prefer the Cabelas conversion.I have had good luck with the Winchester 777 primers(1st choice) and the Remington Kleanbore muzzleloader primers(2nd choice).