Originally Posted by fredj338
Not really. Powder combustion is what it is. Slower powders are still burning when tehy exit the bbl, hence larger muzzle flash. A flash suppressor would be the way to go & reload w/ a slightly faster powder.
As usual, Fred gets it correct. You can download a powder burn rate chart off the internet, get appropriate load information from any number of sites and give it a go. Don't forget the flash supressor.
I used to load 223 in a Thompson Contender, 10" bbl. I used IMR 4198, IMH 3031, Win 748. BL-C2 works also if you can find it. Best results for me accuracy-wise were with IMR 4198 in that particular gun. Glad I saved the notes.