Go to Barnes' site. Add the W's. barnesbullets.com Click on Technical, then .224. Their data(and you need to use their data for their bullets as they're not the same as other maker's bullets) for a 36 grain bullet is there in .pdf format. A 1 in 14" rifling twist is recommended. No loads using Varget though.
It's a grenade, not a gernaid.