I want to do a 18 or 20" build. I have 5.56 in 16 and 10.5. And 300blk in 10.5 Anybody got a long barrel in 300blk or is it not worth it for that caliber. I have/had barrels in steel and stainless from BCM, Andersen, Bear Creek, CMMG, and Bushmaster. All seemed similar in quality and performance. There are some silly deals out there now. What kind of experiences/recommendations does anybody have with the longer barrel platform?