Here it is:
"The CZ hornet uses the same magazine body as the .222 versions. There is a plastic spacer pinned inside the magazine to compensate for the difference in COAL�s. Strip the magazine, look inside and you will see it.
The front of the spacer is tapered, and the rear (the side that goes against the mag body) is flat. Drive out the two pins and remove the spacer. Remove .010� to .015� of material from the flat side of the plastic spacer (I used an end mill, but it could easily done on a disc sander if you take it easy and keep the heat down). Reinsert the spacer in the mag body, level the mag in a drill press, and re-drill the pin holes using the original holes in the metal magazine as a guide. Insert the pins and flair the ends using the appropriate size pin punch, or a dab of locktite to keep them in place.
Usually, that is all there is to it.
Occasionally, a magazine modified this way can cause the top round in the mag to �nose down� a bit which can cause feeding problems. If this happens, it may be necessary to add a spacer or shim to the back of the follower to make up for the angle change. Cut a piece of shim stock the same thickness as the amount of material removed from the spacer, and fasten it to the back of the magazine follower. I have silver-soldered copper shims on them, and TIG welded stainless shim stock to them, and both work equally well. I imagine a fellow could even use epoxy and a shim made from a nickel or quarter coin.
It is easier to do than describe."