I've noticed differences even between identically-patterned models of the same make. I'd recently posted in the Buck sub-forum about a Buck 110LT, regarding an unrelated issue. I was contemplating sending that knife back to Buck for a weak closing pull issue, but didn't want to part with it. That knife's blade has taken the most absolutely wicked slicing-sharp edge, with more 'teeth', than the same-patterned blade in my Buck 111. The 111's blade trends more toward a finer finish (a little less toothy), using the same exact sharpening method I applied to the 110LT. When I'd found the magic sweet spot for sharpening the edge on the LT model, I kept trying to duplicate it in the 111. But they're noticeably different in how they each respond to the same method, using the same tools. Both are very good - but each has its own character of 'sharp'.
Buck advertises their spec for 420HC at HRC 57-59. I'm of the assumption that the slightly 'softer' blades probably take & hold a more toothy edge a little better than the harder ones, for which I guess their 'teeth' might be a little more brittle and prone to breaking away a little sooner during sharpening & refining. Sort of like burr behavior under the same circumstances. I've noticed the same tendency in comparing Case's slightly softer stainless directly to Buck's blades - the Case blades take a toothy finish better than the Bucks, which hold a more refined, but still very stable, cutting edge.
