It’s not risking anything other than a stoppage. I have one sitting on my counter at home. It’s just a little bulged and won’t go fully into battery. AND the shelf brass easy to spot during normal brass prep and loading… you may not have any.
As far as crimped 9mm brass, I toss that in the recycle bucket if I catch it. Not worth the effort like 5.56 is.
There is way too much good 9mm brass out there to worry about using stepped brass. I didn’t know about them when I started 9mm loading and loaded up a bunch of different brands. Now I have junk ammo to blast through as some brass is tighter and not as suited for plated and lead bullets. I now sort brass by headstamp and the harder euro stuff and stepped brass go in the junk pile. The press runs so much better when the brass matches.
I’d think loading a 147 in brass with internal shelf would bulge case so badly it wouldn’t chamber.
But I’m not desperate enough to load one to prove a point.