SB
I am checking for a crud ring when loading the shots after the first. With the standard primers, it is there and the bullet will stop just a little short and some extra effort is require to seat the bullet the last 1/6 - 1/8". Also when running a wet patch down the barrel, you can feel the crud ring and it takes an extra couple of passes in that area to get rid of it. These two signs of the crud ring were not there with the 777 primers.
Before doing some other things a few years ago to minimize the crud ring, I have seen it bad enough in my gun that I actualy stuck a patch in the crud ring and had to remove the breech plug to push the rod through beacuse it would not back out.
alleyyopper
You are right, the 777 primers are a little pricey, I bought mine at Gander Mnt and do not remember what I paid. However, if you buy the standard primers in the blister pack they are also over priced compared to what I used to pay for a 1000 at a time when I reloaded shotgun shells. I only use about 100 primers a year for my muzzleloader and do not reload shotgun shells anymore, so I am not going to lose any sleep over the extra couple of bucks a year.