I have not yet run into a Ruger double action revolver that would lock up if shot fast in DA. But it is certainly true that if you don't release the trigger far enough forward between shots, the next trigger pull will won't do anything other than waste effort.
Most of the time, when the trigger is not allowed to travel far enough forward on the return, the next pull will just let the trigger move all the way to the rear without doing anything at all. However, if you get things just right (or just wrong, I guess) you can end up with a situation where if you pull the trigger, it will abruptly stop short midway through the pull and the action will feel like it's locked. It can be something of a surprise to the shooter if that happens, but it's really not a problem--simply releasing the trigger fully will immediately clear the apparent lock and return the gun to normal function.
There's actually a warning in the manual that not fully releasing the trigger can cause the revolver to not fire on the next trigger pull.
This "feature", by the way, is another reason I'm not a fan of putting reduced weight trigger return springs in the Ruger DA revolvers.
Most of the time, when the trigger is not allowed to travel far enough forward on the return, the next pull will just let the trigger move all the way to the rear without doing anything at all. However, if you get things just right (or just wrong, I guess) you can end up with a situation where if you pull the trigger, it will abruptly stop short midway through the pull and the action will feel like it's locked. It can be something of a surprise to the shooter if that happens, but it's really not a problem--simply releasing the trigger fully will immediately clear the apparent lock and return the gun to normal function.
There's actually a warning in the manual that not fully releasing the trigger can cause the revolver to not fire on the next trigger pull.
This "feature", by the way, is another reason I'm not a fan of putting reduced weight trigger return springs in the Ruger DA revolvers.