The first 50 rounds I run down any new factory rifle are are David Tubbs Final Finish Bullets. They work as advertised. Mr Tubbs, who has probably forgot more about LR Shootimg than most on this site, doesn't claim any accuracy improvements to your Barrel but does aver that your rifle will be easier to clean and harder to foul after using them on top of shooting with less pressure when you are done. Like Boron Nitride coating, you may have to bump the powder Charge to get back to velocity when you are finished, but your bore will be much smoother when you are finished. I've run them down several 223, 270 7mm 338 bores with excellent results and have NEVER run into averse effects. Anyone that equates shooting these bullets with "running sandpaper down your barrel" obviously has no experience with them. It's a lapping compound. 5 different grits of very fine lapping compound. Only gun I haven't shot them down is my 30 Nosler with its Hand-Lapped Pac Nor 26" Barrel. But I have no doubt that if I did, I wouldn't suffer any negative effects. I'm also gonna try his Boron Nitride coatings and TubbDust. Everything else he's told me has been spot on. He has many good products. I called his 1-800 number one morning years ago with some questions about the Final Finish Bullets. I was talking to a man and told him that my 270 WSM was grouping 1/2 MOA already with my reloads so I wasn't looking so much for improved accuracy as it is a "light weight factory hunting rifle and I'm no David Tubbs." The man replied "That's great accuracy from a light weight factory rifle and I AM David Tubbs"! He then went on to relate just what these bullets would do for my rifle- "they won't make your rifle more accurate, but the will make you Rifle more accurate for a longer shooting session." He was right on that statement too. Unless you have a Hand-Lapped Barrel, buy some, follow the directions and you'll be happy. You must start with a very clean barrel. You must clean your barrel every 5 shots. Every time you run a subsequent patch down your bore, you will notice less resistance. When you have finished your 50 shots, the patch will slide down your bore like a ski on snow.