Which bullet would you choose?

[Tangent]

Remember a slow accurate bullet is better than a fast inaccurate one.

True. What if both are accurate? That's my dilemma, fast, light and accurate or heavier, slow and accurate...

 

[Rob01]

True. What if both are accurate? That's my dilemma, fast, light and accurate or heavier, slow and accurate...

Won't make much difference for your 500 yards and if you used a different powder the 178 will be faster than you have it now.