I agree with S.C. on the Sitka Spruce. Considerably tougher than POC and a great shooting arrow wood. I believe the Tomahawk is cut slightly out from center, but 3RA will be able to tell you just what spine you will need. With a 70 gr point, I believe you could use a 5/16 shaft in 40-44 lb spine. I have two dozen, but they are about 300 gr shafts and on the heavy side rather than light. I would recommend not going below 8 gr/lb, or about a 320 gr finished arrow. With a 70 gr point, that would be about a 250 gr raw full length 32" shaft. Normally, I would use 4" fletch, but with the right spine and well matched you should be able to use 3 or 3.5" just fine.