The XD-45LE magazines and how they compare to the:
9mm,  40sw and 357sig magazines.
By James Nicholas

Use this information if you need a 45gap magazine in a pinch!

The twelve round XD-40/357 magazine will hold nine rounds of 45gap ammo just like the dedicated 45gap magazine. Any stock XD magazine will hold and can feed the 45gap round including the 9mm magazines. Please notice how high the 45 gap round sits in the magazines made specifically for the 45gap. You can slightly bend open your feed lips on your 9/40/357 magazines to match how the dedicated 45gap magazines hold the ammo helping with reliability. To help with smooth feeding Springfield Armory has a round cutout on the front top of the 45gap magazine (center red arrow). Without this round cut, the 45gap round is so fat that the case can catch and makes a ka-chuck sound as it feeds from an unmodified 9/40/357 magazines. This clearance cut can easily be made to any unmodified XD magazine with a roto-tool or file. I was able to successfully get several 9/40/357 magazines to reliably feed an XD45gap without any modifications at all. Although as I said the case can catch and it does not sound pretty. With two simple modifications, a clearance cut and opening the feed lips you can make a magazine that feeds as good if not better than the purposely made magazines. You may not ever try these modifications but the information is good to have just in case.