The broadhead has to have thicker blades for it to be resharpenable for sure. I shot Thunderhead 125's for many years when I shot a compound. They had to be THE sharpest blades out of the box of all the replaceable blade heads I ever tried. I'd still be shooting them, but when I went to a recurve, I wanted a head that had a lower blade angle, and a cut on contact tip for the increased penetration. The Razorcaps were my choice.
Originally they were billed as a "ready to hunt" replaceable broadhead that were one piece (or actually two.....a ferrule, and then a three blade single unit that fit over it.)
They were all that EXCEPT for the "ready to hunt" part. But they are VERY easy to get extremely sharp. I use a mill bastard file, and a fluted butcher's steel, and set the arrow shaft in a wooden jig I made. Believe me, if I can do it, anyone can! The key, I believe, is in the three blade arrangement, which eliminates the potential for the idiot human doing the sharpening to mess up the blade cutting angles. All you need to do is lay the file or steel across two edges at a time, and with even pressured strokes, push the file forward on a slight angle. Even I can do that and not mess it up!
It's not a "have to do" thing for a bowhunters by any means. But I do believe it helps extend my hunting season, as it has me working with my hunting tools, and doing something that will have a very direct effect on the next animal I loose an arrow at.
Offer No Apologies.....
NRA Endowment Life Member