[jetrecbn]

I know that the Glock 23 neutered magazine(10) will hold/function with more 9mm ammo. I wanted to know if this is true for other firearms, especially a 40sw Sig 229 in a 9mm 228.

[SouthpawShootr]

As a recall, the 229 .40 frame is a bit wider than the 9mm in the magazine well (I don't know this for a fact, don't have a .40, but I'm certain there was a thread on this over at www.sigforum.com). Bottom line is that the .40 mags are just a tad too wide to go in the 9mm's magazine well.

Really, there is not much of a point to doing what you suggest for Sigs. Pre-ban 228 13 round mags fit and function fine in 9mm 229s. There are lots of these around and you can pick ones up in excellent condition for about the price of new 229 10 rounders.

XD-40 mags will work in XD-9 pistols in the manner in which you suggest.

[10-Ring]

As long as the grip dimensions are the same, the mags should work ;)

[Tacblack]

I do not know about the Glocks, but I can say this works for the Sig 229, Beretta 92/96 and HK P7M13-P7M10

[PCRCCW]

MOST guns that have identical models in 40 and 9mm will cross over and offer an additional 4-5 rnds depending on the mag setup. CZ, Taurus, S&W, Beretta and a few others Ive tried work flawlessly and are a very common and reasonable HI Cap..........
Shoot well