I've tried both the 39 grain Sierra and the 40 grain Hornady and found loads for both that worked very well. As far a stabilizing the heavier bullets, it is hit or miss, pun intended. Some rifles with 1-12" might like them, others might not. You won't know for sure if your particular rifle will like them until you load some up and shoot them. What rifle do you have and can you verify the twist?