Originally Posted by sweeper22
Going from 40sw to 357sig would be "going down" in caliber...not the other way around. A 357sig is a 40sw case necked down to meet a 9mm bullet. If the 357 was larger, it (obviously) wouldn't have any need to be "necked down". That's why 357sig's standard weight is 125gr, while 40sw's is 180. A 357sig shoots a 9mm bullet, while a 40sw essentially shoots a 10mm.
Regardless, you can (in almost all cases) go either way on these calibers when it comes to conversion barrels and bi-caliber mags...because the butt end (70% or so) of the 40sw casing applies to both.
I don't mean to be rude at all, but... DodgerBlue, I'm going to excercise an opportunity to call you out a bit here- based on some of your previous posts claiming that Glocks are the be all/end all...and that archaic guns like the BHP can't hold a candle to them. Well, your limited experience is now officially confirmed. Glocks are very good and very reliable guns BTW, and I wish you nothing but the best in your experiences with them. But you have a great deal to learn. I should know, as I'm in that boat myself. But maybe keep a bit more of a humble, open-minded approach going forward.
Nobody likes a know it all.
"if you're going to barrel swap you can only go down in cal. it might take some research but I think you need the .357 and then pop in the .40. I don't know
with the .40 will take a .357 barrel.
I simply pointed out what might need to be taken into consideration.
Hope this helps or if you already knew all this maybe it'll help someone eles