SBR bullet weights

[turnandshoot4]

I have a SBR'd HK 91 coming and the previous owner told me that the barrel can't stabilize heavier bullets. I can understand that, but what wiill it stabilize?

I have some 110gr and a WHOLE LOT of 145gr bullets. Anyone know what would work well in this? The barrel is about 10 inches with 18 inches OAL with the permanent suppressor attached.