I really want a heavy bullet that I can use for hand loading at least a 200gr FMJ Flat Nose, but larger if at all possible!
The heaviest 10mm loading I know of is Double Tap's 230grn WFNGC, but it uses a cast bullet so an aftermarket barrel would be needed to shoot it in a Glock. Really, a 200grn or even 180grn FMJ is going to give you plenty of penetration out of a full-power 10mm. Remember that while the .45 does offer slightly more weight, the 10mm's smaller diameter will offer a better cross-sectional density for a given bullet weight.
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