Gartenmeister:
A few years ago I was told by a Winchester factory rep that they cannot officially sanction the use of the 980 fps AA loads in any old gun (think Damascus) but that they "would probably be safe."
Take that for what it's worth. At 980 fps., I don't think you'd have a problem.
The reason they won't sanction those loads is because they don't necessarily use the same powder from lot to lot. They're working to a specified velocity. Their only concern with pressure is that they stay within SAAMI standards. As Kensal says, with sub-1000 fps loads, chances are pretty good pressure will also be low. But you don't know for sure. A few years back, Federal did a special run of low pressure 12ga loads that were sold through Midway. But other than exceptions to the rule like that case, there's no pressure guarantee on shells from the big outfits like Win/Rem/Fed. Best thing to do is to buy those AA's, shoot them in a gun proofed to SAAMI standards, and then work up low pressure reloads in the once-fired hulls.
