riser length

[pinecrest]

Shooting a C mag 41#@32 #1 limbs and a B mag 49#@32 #3 limbs.Both like a 2018 inserted  with a 125 grain point.What gives?

[Orion]

Though there probably is one optimal arrow spine/weight/length to bow draw weight/length set up, most of us aren't good enough to find it.  Luckily, Most bows will shoot a range of spines well, particularly if they're cut to center or past center as the mag risers are.