In general it's a bad idea to use the softer standard primer in a gun with a floating firing pin. That's what the #34's are for. Read the posts by Slamfire in this thread
to see why. I have no clue what the fellow at CCI was thinking, but the article is by Alan Jones who worked for CCI and you could probably write him for a second opinion. Very odd. All I can think is he meant you should not substitute a magnum primer into load data for a standard primer, and that's so. You want to knock an extra 5% off the starting charge weight for it, just to be sure. Mostly though, with large rifle primers they wind up making surprisingly little difference; less than you see with small rifle primers.
If you want a military hard primer that is not magnum, then look for the TulAmmo KVB762.