David Tubb's
Final Finish
This product looked interesting, and I wanted to see how
well it would work on my Browning A-Bolt rifle (300 Winchester Magnum). The Final Finish instructions recommend using different
procedures for factory production barrels, according to their level of accuracy. I have used other firelapping products before with fairly good
results, but I thought this product might be even better. I've found that when shooters like David Tubb (10 time Highpower record holder)
suggests a shooting related product .... you should try it. Final Finish first got my attention because unlike other lapping kits, their
abrasive lapping compound covers the entire surface of the bullet. This includes the ogive which is the first part of the bullet to contact
the rifling.
After completing the fire lapping procedure, I'm sure that the entrance
of the rifling is now the exact same shape as my bullets. However, I found that the rifling is now about .016" farther away. This is
logical, but it was a bit more than I expected. I chronographed my favorite handload both before and after the fire lapping, and found that the velocity
was increased by about 40 fps, but the accuracy was noticably reduced with this particular load. I was prepared for this to happen, because the barrel went through
some major changes. My barrel now is 10 times easier to clean, but I discovered that I now have to work up a "new" favorite handload. The
factory tool marks in the bore have been polished out, and there is about 98% less copper fouling (even after firing 20 hot handloads).
This rifle barrel used to copper foul very badly after just 3 shots. I was confident that the accuracy would improve after I could shoot
a few groups with different bullets. This firelapping process only removes about .0003" form your bore diameter (that's about one tenth the thickness
of a human hair). I was determined not to quit on this rifle until I found a new handload that would out perform my original favorite handload. Be sure to read
the directions that come with Final Finish. It is far better if you use a borescope during the firelapping process. You should expect your rifle to perform
better, but don't expect miracles unless you are willing to take the time to work up a new favorite handload.
My next few trips to the range were even more encouraging. I shot a few (5) shot sub MOA groups with the 180 grain Hornady SST
bullet.
This was great news because this rifle had never performed well with bullets over 150 Grains. I now have two new "favorite" loads that consistently
deliver almost 3/4 MOA accuracy (that's outstsnding for a factory rifle). This Final Finish is a great product. Very impressive!
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