I agree with Stats Shooter on powders. I've had some good results with H322 as well, but with lighter bullets than you are shooting. Varget works best for me with the 75 to 80-grain bullet weights. IMR4064 does well with those bullet weights, too, but in the small case volume I generally weigh loads and dispense through a drop tube for best consistency of load density. Among spherical propellants, 748 has done well with those weights, too.
You may have chosen CFE223 for the copper fouling reducing additive. Be aware you can buy copper fouling reducing additive to add to any powder you have.
G. David Tubbs sells it as TUBBDUST. Adds about $1.30 to the cost of a pound of powder.
Ignition is an issue for all spherical powders because they burn from large combustion surface area to smaller (as opposed to stick powder perforations which burn wider from the inside out, thereby increasing burning surface area as they go). So, making spherical grains burn progressively (making gas at a progressively faster rate as the burn continues up to the peak rate point in the characteristic curve) requires a deterrent gradient that starts out pretty highly concentrated at the surface and rapidly fades to lower concentration as the surface shrinks, letting the remaining powder burn faster. The high exterior deterrent concentration means adequate heat and start pressure are required to catch, spread and maintain the initial rate of deflagration.
If you look at primers made in the '80s, the flames are mostly transparent-ish in ignition photos (when German Salazar maintained The Rifleman's Journal blog, there were lots of such photos available, but alas, gone now unless you find copies of his articles elsewhere). In 1989 CCI introduced 24% hotter sparks and 16% higher pressure from their magnum primers for igniting spherical propellants through their high concentration deterrent coatings better. The heat comes from the addition of a barium compound and from metal particles that make the flame white hot and throw a shower of sparks. But that higher pressure in some smaller cases can result in increased velocity SD.
Today, standard primers made in the US typically make the white-hot spark shower, too, so formulations have changed since 1989, and you may get better velocity consistency in a smaller capacity case like the .223 Rem by using modern standard primers with spherical powders. Unfortunately, the different makers all formulate primers somewhat differently, so there is still variation in flame temperature and gas volume among them and these often change without notice. The bottom line is you just have to be prepared to try a number of primers to learn what works best. You will need a chronograph to observe the difference in velocity SD. It is the only convenient way to select one.
I had the experience with Accurate 2520 years ago of my M1A groups with it being half-again bigger than my stick powder groups. I tried a number of things, but found deburring flash holes actually got the groups down with the stick powder groups. So, in addition to the best primer, a clear ignition path may help.
Carefully seated primers will almost always help. One way is to use a tool that lets you feel when the primers just kiss the bottom of the primer pocket, and when they do, measure how far below flush with the head they are, and then go back and push them in another 0.003" to compress the priming mix with the anvil of the primer by that much (called either Setting The Bridge, or Reconsolidation). You will quickly learn what it feels like to get them the right depth and be able to do it without stopping to measure the kiss point.
That 0.003" number was found to be ideal by Naval Ordnance at Indian Head in the 1980s and remains a good general recommendation today. Since primers keep changing, you can call the maker of the ones that work best for you to confirm that recommendation is valid with their product. Most primer makers have their products in commercial ammunition for which they have determined best seating for setting up their machines. Just be aware they will often just tell you how far below flush to seat them and that they will have made that determination with their brand of bulk brass, so you want to know their average primer pocket depth as well to compare to your own.
There are different ladder approaches.
Newberry's OCW method works for most folks.
The original Audette ladder works most of the time. The
velocity flat spot ladders have gained popularity but based on Dave Milosevich's description of their limitations in the 1995 Precision Shooting Reloading Guide, they aren't guaranteed to identify the very best spots without checking them against an Auddette ladder or and OCW ladder for synchronization.
