According to Lafayette Parish Sheriff Office website it says it open to the public on Saturdays, but you have to "qualify", not quite sure what they mean by it, I sent an email to their info center but I'm still waiting on a response.
I am a Range Safety Officer at LPSO. It's open 8-1:30 ish on Saturdays to civilian shooters. The only 'qualify' is that if you are new to the range you must sit through a short safety demonstration and sign a waiver form. It is a great place to shoot, very friendly RSO's and has 15 pistol lanes, a 50 yard range for rifle/pistol/shorgun, and a 100 yard range for rifle. Only drawback is that the 50 and 100 yard ranges are like a swamp after a rain, so count on wearing your white rubber boots.
Almost forgot...no laser sights (outdoor range under air traffic flight lane), no armor pericing/incindiery/tracer ammo and NO BUMP FIRE.
The LPSO range is on Michael Ann Drive in north Lafayette Parish.
Take Pinhook Road towards the Breaux Bridge Highway, cross the BB Highway, drive past FR. Terulings HS, cross the tracks, take the first RIGHT on Lajaunie Road, cross the bayou, take an immediate RIGHT. Michael Ann Dr will be the first road on your LEFT. Go all the way to the end of Michael Ann.
If you go to Mapquest.com you can see the range in the satellite photo...
Open to the public Saturdays, 0800 - 1400 Central, except holidays or the Saturdays after holidays if the holiday is on Friday.