If all you want is the performance of the Hornet, keep the 223 and load accordingly. The 223 brass is cheaper by far, readily available at any shooting range for the picking up, and it seems you are already set up for it. Hornet brass is delicate, and sometimes hard to find. You can get up to a dozen loadings out of 223, more if you don't step on them too hard and use cast bullets. Hornets usually split after 3 or 4 loadings. If you are drawn by the nostalgia of the old load, go for it. I have 2 of the hornets and only one handi in 223, so I can't preach too much.