I've been well satisfied with my 16" WOA SPR in .223 Wylde. It was a little picky in handload development but is a great shooter. Thanks MarkM for the H322 powder recommendation.

Actually my very best MOA grouping out of this barrel was .685 MOA at 400 yards or 2.74 inches. It will consistently shoot between .75" to 1.0" at 100 yards all day long.