Peugeot UO-8 (early 70's). removed cottered cranks and BB. French threaded obviously.

Friend had this bottom bracket: Campagnolo 68-SS-120, French (112 mm), Nuovo Record Strada, BB-NR68SS120F.

fixed cup goes on smoothly. lockring cup, however, will spin on about 5 threads deep and then near impossible to get tighter in there. Old BB seems not to have a problem though...

Are these not compatible? Did my BB threads get ****ed up somehow? I'm a fairly naive DIY bike hobbyist, fyi. HELP!

thanks