Tweaking my flies a bit and was wondering before I bought a bunch of meerger hooks, does anybody tie their dry flies on emerger hooks? I read an article some time ago in maybe Fly Fusion that the author claimed he tied his dries on emerger hooks in the smaller sizes for better hookups. I tie spent patterns mostly like x caddis and comparduns with an occasional bettle or ant. Another question, what size emerger hook matches up with a tmc 100 22, 20, and 18 dry fly hooks shank length.
The term “emerger hook” to me is a bit misleading because any dry fly or even standard wire hook can be used to tie an emerger. I would hazard a guess that the article you read was simply alluding to the fact that if you use a shorter hook style, you get a larger gape. For example, a Dai Riki 135 is a 2XS hook, and therefore has a gape in the neighborhood of a dry fly hook two sizes larger. Now proportions are rarely constant so if you get out your ruler and find this is not 100% accurate, do not be surprised, but it is a reasonable rule of thumb.
I also use DaiRiki 125 for small dry flies. If you tie the fly on the straight part of the hook shank (ie, not into the bend), you end up with a small fly size that hooks much better than a standard hook. In small sizes, #18 and smaller, I don’t think it impacts floatability.