I've been tuning my arrows for my 45lb at 28" recurve bow. I have 2 different weight arrows both of which seem to be bareshafting pretty well. Both arrows are 31" goldtip traditional carbon, one of the arrows has a 100 gr brass insert and a 150 head for a total weight around 510 grains. The other arrow has a 50 gr brass insert with the 150 gr head for a total weight around 466 gr. The weight dirrence between the 2 arrows is 44 gr. I can't see much of a diffence in speed when shooting these arrows with the naked eye. Will this weight difference make much of a diffence in penetration and speed?
Without chrono numbers we can't give you a KE number. Where are they hitting the target in relation to each other? How far are you shooting? Under 20 yards you shouldn't see that much difference and 8-12fps would be a normal difference in speed. If they both fly well, go with the heavier and give yourself some insurance.
Step back a little farther and you should see a difference.Both are more than enough for deer sized animals to worry about penitration.
James is right.
Shoot both at 40 yard targets and you will definitely see the difference. For deer size game, the 466 gr. would be my choice from a 45 lb. bow.