Doug fir makes for excellent shafting, too me its only downside is that its a bit heavy, Sitka spruce on the other hand( not the "german spruce " mind you- its a completely different specie) is incredibly tough, and its quite a bit lighter.
I find that this allows for a higher FOC arrow, without getting an overly heavy arrow.
from what i have used, and measured: using lighter weight shafts for my #50 RD bow
with a 125gr point i get an FOC of 13% with an overall mass of about 530 gr- still 10gr + per #
however if I
taper back 8” to 5/16, it will give an FOC of 14.3% and a mass of about 500 gr ( lighter than the parallel shaft setup)
Taper back and add 200 gr pt =FOC of 20 % and a total mass of around 580 gr.
20% to 30% FOC is considered an EFOC!
And for heavier hunting arrows, For when I go hunting back in africa regularly- i just use heavier Sitka shafts to get my overall weights up.
Sitka has an exceptionally long fiber, longer than other woods, and thats what really hold it together well- Sitka is considered to be the strongest wood for its weight in the world ( but of course they can still break on a glancing shot).
I guess thats why it was the preferred wood for airplane frames and for masts and spars on traditional sailing vessels!
I get many thousands of stumping shots from sitka shafting, but like mentioned above, premium shafting is the key. Nice clean shafts , minimal runout!