According to Goldtip's site, your setup could fall in group 4 or 5, with group 4 being 5575's and group 5 being 7595's. I shoot the Alphamas at 29" 70 and shoot as .340 spine with no spine issues.

IMO, it would best for you to shoot a .340 instead of a .400 spine, but I don't believe you are under spined enough to cause the problems you are having.

Since you are shooting a fixed blade bh, I believe your bow is out of tune. Have you shot field points? If so, how did those groups look? Have done any tuning to the bow at all or are you shooting it right out of the box?

I would start by shooting it through paper and seeing what kind of hole you are getting. Then you can move on to bare shaft tuning and wrap up with walk back tuning. If your bow is in tune, you should be able to shoot your fixed blade bh and have the same poi as your field tips.

If you are not familar with any of the tuning processes, I would suggest taking your bow to a good pro shop and asking them for assistance with tuning it.