I always get such great advice here. I have 6mm PPC barrel laying around. I think the twist is 1-14. I want to build a 6mm/223. Is this the correct twist? What would be my ideal bullet choices?

With a 1:14 your likely best off with 75 gr and under slugs, mostly the 1:14 is used for shortrange (100-200yds)benchrest bullets in 66gr.or 68gr. I have 1:14 and 1:12 twist barrels and can stabalize up to about 80-85grainers with the 1:12. 90gr's if I can drive them fast enough but they are on the borderline. A 6mm 223 will not give you the speeds you can get with the 6br so your going to be stuck with the lighter bullets in that 1:14 twist.

I have a 6MM-.223 (aka 6 X 45) with a 1:14 douglas XX barrel and shoot the 55-58 grain bullets as well as the Hornady 70 grain SX. All is fine with this and I like it.

If I was to do this again I'd use the 1:12 barrel for sure.