what would i need to convert my 9mm 24/7 to .40?
(ps dont say just buy another pistol, looking for a combo)
i'm guessing a slide assembly, barrel, recoil assembly and maybe an ejector.
i think the 9mm mags may work.
Yes, you will need a complete Slide Assembly, as the 9mm Slide boltface and extractor are sized to accept only a 9mm sized case head. Trouble is, by the time you get done buying the parts, you may have spent the same money as another complete handgun.
Having all those extra parts will not add much to the value of your existing handgun, unlike Europe, where Caliber Conversions are much more popular, due largely to the Red Tape involved in purchasing just one handgun!
One possibility, should you wish to persue it, is that I have seen 24/7 parts kits on Gunbroker.com, but I believe that these may be salvage from Police Confiscation distruction.
The way it is usually done is to buy a 40 cal gun then buy a 9mm conversion barrel. You can't do it with just a barrel change the other way around because the 40 barrel is bigger around than a 9mm to start with. jwc007 is right that to buy a top end will cost you probably as much as a gun if it will work. Mark