Your 40's should work in a pinch. Worse case they may spin apart before hitting the target with the thinner vmax's having the most potential but I think they will be just fine. You aren't running them out of a 22-250 or creedmoor. They aren't the most ideal but I bet you get a little more action on living targets with them than before.
Your mag length isn't ideal as Stick pointed out but it isn't the end of the world. You might be able to tweak the magazine like some have done with Tikkas either filing out the front for more lateral room or if there is a spacer in the rear you can remove you might be in luck there. Otherwise you are stuck single loading or going with AR mag friendly rounds which there are a decent amount to choose from.
I would consider the Hornday 75 BHTP, or the 73 ELD or as mentioned the 77 TMK from Sierra. If you can get the RMR 69 grain or their new 75 grain which is similar to Horn's BTHP that would be a great economical option. I think Nosler has a 77 grain bullet to fit the AR mag confines as well.
