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View Full Version : Barrel/Throat break-in w/ Superior Shooting System, from David Tubb


GripItRight
October 21, 2008, 17:22
Anyone here use the Superior Shooting System (SSS), from David Tubb, for their barrel break-in?
http://www.davidtubb.com/about_sss.html and http://www.superiorshootingsystems.com/

Your competent gunsmith chambered this handlapped barrel with his (hopefully) sharp reamer with a floating pilot matched
to your barrel. He likely even polished the large diameter (body wall portion) of the chamber in order to uniform and smooth
it, which will aid in extraction of a fired case. He did not attempt to polish the lead area of the chamber (this is the portion
between the chamber and the full height of the rifling). (If he used a solid pilot reamer to cut the chamber, you now have some
slight tool marks in front of the lead/throat area on top of the rifling from the pilot not turning with the barrel.)
http://i310.photobucket.com/albums/kk440/gripitright/SSS.gif
With the barrel turning in the lathe and the reamer held stationery, the chambering procedure has effectively put little “speed
bumps” (tool marks) into the leade/throat area, much like how drilling a hole through metal typically leaves large, circular
rings. These are found in every newly chambered barrel. These tool marks need to be smoothed out before the rifle will begin
to shoot its best groups. One idea exists to go shoot the heck out of it with full power loads and never look back, while others
recommend the tedious process of clean and shoot, clean and shoot, clean and shoot, clean and shoot some more. The idea here
is to send one bullet down a clean bore in hopes that it will remove the tool marks, but this process is going to take a while. I
have seen several barrels broken-in using this method that still exhibited tool marks throughout the leade/throat, even after having
been shot several hundred rounds.
Why did your custom barrel maker lap their product to begin with? This process was done in order to uniform the internal
dimensions with the end goal being an accurate rifle barrel. Why wouldn’t you want the same for your newly cut chamber
throat?

After several hundred rounds, it’s likely that the tool marks will have been removed from the leade/throat. However, during this
same time/use period the barrel is now exhibiting a stress-cracking presence in the throat and down the barrel a few inches.
This is normal and occurs in every barrel. (There likely could be cleaning rod wear marks appearing in the rifling too from all
that cleaning — remember, shoot clean shoot clean shoot clean…) After several hundred rounds, you now need to think about
some sort of scheduled maintenance on the roughened throat (from the fire/stress cracking). This is what TMS (Throat Maintenance
System) was designed for. Use of this product is kind of like changing the oil on the car that you broke in correctly
(and those first 500 miles/rounds came quickly) and is now being run/shot at high speeds (with full power loads).
Arough throat in a barrel compromises the bullet jacket’s integrity as it travels down the barrel (kind like all of those tool marks
in the leade/throat when the barrel was new). When the throat becomes rough enough to tear or mar the bullet jacket the barrel’s
accuracy will deteriorate.
Again, one certainly doesn’t want to start his new barrel off with full-power loads since high pressure and velocity equate to a
fouled barrel (the bullet jacket material left in the barrel is not our friend). This condition is not conducive to accuracy, and,
again, is kind of like driving that new car at 120 miles per hour from the start.
Two things need to occur for optimum barrel break-in —
FIRST STEP
Handlapped Barrel (use TMS kit)
Remove the tools marks in the leade/throat of the handlapped barrel. This can be easily done using about 10 TMS bullets.
Factory Barrel (use Final Finish kit)
Remove most of the tool marks, imperfections, and reamer smudges in the factory barrel by using the first four grits of a Final
Finish kit (compartments 1-4). That is done by firing 40 bullets loaded with a light starting-charge load. The first two grits (located
in compartments 1 & 2) do about 70-percent of what is needed, and if I had only 20 shots to use these would be my pick.
All right, we have done the above according to the type of barrel we have. The barrel’s tool marks are either removed or greatly
lessened.
NEXT STEP
Handlapped and Factory Barrels
We now need to burnish in this now uniformed barrel.
“Burnishing” is the metal-to-metal finish that acts like a hone on a razor edge. It doesn’t remove metal but smoothes its finish
and also, in a rifle barrel, orients the finish in one direction. Some relate this to a feathering effect — the feathers on a bird all
lay the same direction for ease of aerodynamic flight. We burnish the barrel by shooting Final Finish #5 (bare) or your own
handloaded bare bullets through the bore, best accomplished with a starting-charge load (lower pressures) from your reloading
manual. This puts a finish on the barrel, which is conducive to minimize fouling. (This is now basically the process that all the
clean-and-shoot group recommends — but they need to remove the tool marks first!)Anyone here have experience with this product?

Grip

GripItRight
October 26, 2008, 21:06
Bump

And here's the product: 308 TMS Ammo (http://www.superiorshootingsystems.com/DTAC_TMS-308_TMS_Ammo.html) and 308 FF Ammo (http://www.superiorshootingsystems.com/DTAC_FINAL_FINISH-308_FF_Ammo.html) and what it does (http://www.youtube.com/watch?v=T6p4mM489B4&feature=related).
http://i310.photobucket.com/albums/kk440/gripitright/18108114.jpg
Grip :shades: