I recently got a 223 Rem. to go along with my Swift and have yet to reload my first round for it. I have a box of Hornady 50gr SX's and would like to use them but have no experience with the 223. The only powder I have for its range would be W748 right now. It has a 22" barrel and 1-12" twist and shoots the cheap Win/U.S.A. brand 45gr. ammo into .9-.7" groups. I'd like to stay with the 40-50gr bullets as this is only carried for my 250 yard and less shooting. Dies come in next week so I have plenty of time.

W-748 is an excellent powder for the .223 with 50 gr bullets. Along with H-335 and BLC-2, it is among my favorites. I don't have my load data with me, but will post a load later if someone doesn't beat me to it.

My CZ527 likes that bullet over Benchmark. I can't remember the exact load, but 26 grains sticks in my head for some reason. Check your manual (or several) before using that though.

My 700 VS in 223 really likes AA2230. 24.0g with both 50 & 52 grain bullets have worked very well.

Hollywood

Try 28 Gr of 748 under any 40 Gr bullet. You won't be sorry.
Pete

Sounds like your set. If you get a chance later try some H4198 with that 50 SX. My 223 loves it.
David