Originally Posted by
Landshark9025
emphasis mine
I would question this. You may be right and it would be worth checking, only because my experience has been different. I have a S&W Mod. 66 that I shoot mostly 38 SPL loads out of. I use CCI-500 religiously. At one point during "The Drought" (I think it was 2015) I tried some CCI-550 and got a lot of light primer strikes. This was the only time I experienced that. I was trying to do some load workups to see if there would be a difference and it happened often enough to make it not worth it. I'd say at least one every 10 rounds.
This particular revolver is old, I acquired it second hand and it had been shot a lot. So it's possible it has a light spring or a worn firing pin. All I know is that with this particular firearm, in the several thousand rounds before and after, using CCI-500 I never had a failure, but with the few I tried with CCI-550- it was pervasive.
Naturally, this was all using the same cases, same press, same everything else.