Yep -- have only had a chance to put 100 rounds through mine at an indoor 25-yard range thus far, but those 100 fed flawlessly (50-50 CCI Maxi-Mag solids and HP's).
As with the .22 LR version, most 597 mag shooters don't top off the magazines from what I can tell. People seem to keep it to 5-6 rounds. Actually, I've only heard of one 597 owner who reported being able to completely top off his magazines without any trouble. The mags are very inexpensive (about $10 online), so IMHO, you're better off having extra magazines rather than trying to cram in rounds (I have 11 of them...).
Using a Nixon Prostaff scope, the rifle was shooting spot-on at that admittedly short range, until the shots started drifting. I realized the screws were coming loose on my Weaver rail.
Haven't had a chance to try it out again since Loc-tite-ing the screws.
My admittedly limited impressions are that the 597 mag is a decent semiauto rifle, with a good "big rifle" feel and solid reliability, especially if one doesn't push the mags.
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