Epj, you might be okay with Clays if you stay with really wimpy loads. I have friends who load Viht N-310 in their .40s, behind 155gr. bullets, for use in IDPA matches where they know they won't get chronoed. (Yes, I sometimes run with a shady crowd.) N-310 is a few notches faster than Clays. I've shot some of them, and it's about like shooting a .22 WMR.

Be careful, though. One of the reasons so many .40s have kaboomed over the years has been reloads that had insufficient neck tension or crimp, allowing the bullet to get pushed back in the case deeply enough to dramatically increase pressures. Case capacity in .40 S&W is not a lot, anyway, and it doesn't take a whole lot of reduction to spike pressures.