I will tell you one of my favorite Benchrest Stories.
At a Nationals in Kansas City about 8 years ago, the eavening before one of the 200 yardages, Larry Bagget went to a local gun store and bought a pound of 4895. He drilled the flash holes out to the standard size, and came out the next morning and won the 200 going away.
All of his groups were nice and round, I think he might have agged in the "teens".
Keep in mind, Larry is a VERY good shooter. He knew exactly what he was doing.
It sure got my attention. Have I ever tried it? No. But I might yet.