01-21-2014, 06:51 PM
LongRanger Wrote:I have solved my AR-Stoner barrel short chamber problem on one of the two 18" barrels that I have and expect this solution to correct the second one also. My original OAL with Hornady 6.5 mm 123 grain bullets with this barrel was measuring out at .2445 to 2.446". Factory A-Max measured 2.252" with my caliper so I felt it was unsafe to shoot that load. I loaded up 50 Tubb's final finish bullets at 2.20" and at minimum loading as directed. I fired 5 rounds at a time and then cleaned the barrel. I ran through the five grades of finishing compound totaling 50 shots. After the Tubb's final finish, the measured OAL for that chamber had increased to 2.300". Must have had several rough spots in the throat that got polished out. I also picked up an increase of 23 fps to 2443 average with the Wolf MPT 123 grain ammo (2.23" OAL) that I tested before and after the above treatment. ES and SD before was 22 & 11 and went to 9 & 4 after the Tubb's final finish. The overall length of this chamber is now identical to my original 6.5 grendel 24" barrel. I will be ordering another Tubb's 6.5 mm final finish kit to shoot through the other 18" AR-Stoner barrel when I get back from working offshore for the next two weeks. It cost me around $50 total to fix this problem which should not have been at my expense to begin with. Tubb's FF is around $38 at MidwayUSA and you must be a reloader to take advantage of those bullets.
Thanx for your post.
It would be nice if Saturn would get some at a volume discount and send to those with any barrels that are problematic.
The Tubb's FF is a good remedy for these barrels.
If it's just a rough throat and not being able to reload I think shooting a few bullets(hornady 123SST's) and cleaning with JB's or flits every 3 shots might smooth things out after a box of ammo.