Obviously this question is for companies that do not make practice tips. What works good to keep the blades from deploying on a mechanical head without throwing off weight or balance? I'm just looking to take a couple shots into my field point target to verify their flight characteristics. I also don't really want to dull the blades on a head simply for this purpose but I will if I have to. I'm in possession of only one three pack right now so that's the reason for me being stingy about the blades. If I had more tips on hand, there would be no issue with setting one back as a practice tip.
Sharpening blades is a bowhunter skill we should all have so dont fear dulling the blades and with the proper tool to rehone the blades you dont have to fear shooting the heads into foam or deer and unless they get bent, you dont have to spend $ on new blades, just resharpen. I happen to know a guy that sells a great broadhead sharpening guide for broadhead blades that costs less than one pack if replaceable blades and is fool proof in its ease of use..
If they don't have practice blades to use, I'd pick one head to use as practice and leave the others for hunting. Or get some replacement blades and keep one set of blades for practice.
^THIS^ I sacrifice one broadhead to make sure they fly like my field points when I face the same thing. A necessary evil, but it pays to be sure.