I converted my standard capacity XD(M) magazines to comply with the California state required limit of 10 rounds. The magazines need to be PERMANENTLY modified to the new capacity. I use a two-part hobby epoxy and two pieces of metal per magazine. These items cannot be removed or changed without the use of several tools.
Disclaimer: These modifications have not been legally approved by the CA DOJ. Use at your own risk!
Here is how I went about doing it:
1. I bought some 1/2” wide angle braces at True Value
2. You also need: A hacksaw to cut the metal and some two-part epoxy.