Ya I have used them on a couple bows, worked fine as sinew. They were a little crusty on the outside of the sinew, a tiny bit harder to beat out, but not by much. Worked fine. I suggest you degrease it all though, I didn't, but they were really greasy and I really should of. Different brands probably do different things to them, some probably cook theirs, etc. I don't know about all brands, but I bought the moo brand cow tendons. I used a couple individual achilles tendons you can buy, and I bought a couple 1 lb bags of them too for pretty cheap over the internet. It's definitely better getting them from a butcher, but it works too. The glue seemed to crack a bit when I used it, but I think I made the glue too thick. I'm thinking it's my fault, not the sinews. They bows were snappy and held (and gained over time) reflex like any other sinew backed bow, so I give em a thumbs up,
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