IMO accuracy lies within a barrel more so than the action so no your howa isn't going to hurt anything. 6XC is a fine choice! I've been wanting one for some time now but have decided to rebarrel my rifle to 6.5x47L and have a 6XC built down the road. Almost all cartridges created with the 30 degree shoulder stand out as accurate cartridges, 6mmBr, 6XC, 6x47L, 6.5x47L, 6mmSLR, 6.5SLR, etc.
I like the 6.5 bullet a lot but if were talking 6.5x.284, scrap it and go .284 winchester or .284 norma. The 140gr 6.5s get outpaced by the .284 180gr berger VLDs. 7WSM and .284 winchester have very comparable ballistics, and i've seen people take them out to 2000yds and take Elk at 1380yds. It's ridiculous.
I like the 6.5 bullet a lot but if were talking 6.5x.284, scrap it and go .284 winchester or .284 norma. The 140gr 6.5s get outpaced by the .284 180gr berger VLDs. 7WSM and .284 winchester have very comparable ballistics, and i've seen people take them out to 2000yds and take Elk at 1380yds. It's ridiculous.