For .22 BPCRA silhouette I use a Steven's 44 that was rebarreled with a Shilen Ratchet Barrel. I was checking out the throat & bore of my rifle after the match on Saturday. No carbon found in the throat after soaking with a patch of C4. Just thought you’d like to see what ratchet rifling looks like with a bore scope. See the photo below. This is a right-twist 4-groove bore & the leading edge of the rifling is the upper darker edge. Since the grooves are cut with a tapered cutter, the deeper edge casts a larger shadow. It supposedly gives less deformity to the bullet and makes the barrel easier to clean. Less deformity means the wind will not affect the downrange trajectory as much. When researching a lot of Internet articles on the subject the consensus is ratchet rifling offers no benefits over high-quality barrels with conventional rifling. But many bench-rest target shooters would disagree since Shilen ratchet barrels are one of the two main barrels used. The other is Muller minimally invasive (MI) rifling. With a high-quality barrel, I believe the key is to have a tight match-grade chamber that forces the bullet nose into the leade. So far I've been very happy with the ratchet barrel & match chamber.

BTW, the new barrel & chambering work was done by Tom Klinger out of Florida.

Wayne