Worst case, you can forget calculating SD and just look at the raw data. Are the velocity listings pretty consistent? That's a small SD. Are they varying quite a bit? That's a large SD.
Not very sicentific, but that what SD is measuing--consistency of the individual pieces of data.
If you don't need the SD number for comparison between batches, I tend to agree with Monster. What matters is how they shoot.
But if you're a bench rester, or a scientific reloader, you have the options listed above.