I've been using aluminum (front) inserts for nocks for years. Just polish off any sharp edges that might nick the serving with a piece of fine sandpaper or steel wool and they work fine.
Sorry, but I don't buy in to the super high FOC is necessary for good accuracy belief. I've never found it necessary to add weight to the front for good accuracy at hunting ranges (I set a 35 yard personal ethical limit on deer with my Phoenix). Even at 50 yards I don't shoot two arrows at the same spot when practicing. But I use aluminum shafts that are straight when I build a batch of arrows. No need to "spine" them, either.
I've used 2213, 2215, 2216, and 2219 shafts and all shot well. The heavier the shaft, the longer it will stay straight (and accurate), but most damage is usually inflicted from pulling arrows from targets IMO. A good (Danny Miller) arrow puller used carefully will add a lot to the life span of arrows.
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