Got a 12T 527 223 as well,it's the LUX model. Have a scope for it but only use it for load development.... then it's back to the factory irons.
It is my favorite iron sighted rig. I shoot milder cast loads out of it. The one 223 bolt that is the go-to for scoped rigs is a '16 R700 ADL sporter. It is stupid accurate,like bragging groups @100 with.....
Lee 225-55RF loaded to a med hard jam with mostly "hardball" but with about 20% range scrap thrown in. Water quenched running the mold hot enough to just get some frosting. I don't size the whole bullet in a Lyman 4500...
I run a custom top punch that covers the whole nose section. The GC is installed on a beautiful little jewelry C frame press,which very nicely centers the check on the base. A lot of attention is paid during this initial install,to include rolling on a flat plate making sure the GC is deadnuts. THEN,it goes to the 4500 where only the check,and half of that lowest drive band get run in. BTW,the handles on my 3,4500's are torque wrenches. These allow "setting" not only the check but insures any manipulation of the bore ride section is controlled through extreme repeatability.
On this ADL,the as cast nose is deadnuts for diameter so dosen't need to be bumped or taper swaged..... love this Lee mold. It is also one of,if not THE most perfect round dropped as cast. The torque wrench is pretty durn slick.... once you note the yield point on that batch of bullets. Then stay under that #. I also use clicker style torque wrenches. They're faster,once you have your yield #'s.
OK,where were we....
Back to the flat plate for another check on the GC. No lube gets applied with the lube sizer... just gets the GC crimped. Next is knurling,and roll sizing of the body... a process I developed a few years ago. The knurling plays a part in holding,or slowing down the release point of the lube. It's also part of the roll spinning process. Look at 22 rimfire bullets,along with swaged target 38 bullets. Way too complex to discuss here.
The lube is ONLY applied to that tiny space above the GC... and done with a small Schrade pen knife that's been on my loading bench since the 1970's. I use BW/vaselatum (vaseline base product) in a 3-1 ratio.
H4198 to about 2800fps. I won't even tell you what typical 100 yd 5 shot groups are except..... you're gonna want a moving backer cause nobody will believe it otherwise.
A little more to it but that's the gist. I'll look for a pic. Look at the land engraving,they're all exactly the same length,tough to photograph.