Interesting results w/ JB Bore Cleaner

[SS427]

A couple of the people helping me learn the ropes about precision shooting recommend cleaning with JB. One cleans with it all the time and another on this forum, Frank, suggests a through cleaing every couple hundred rounds after the accuracy edge drops off to get out stubborn carbon that routine cleaning with solvents don't remove.

I recently cleaned a factory Remington .223 with JB bore Cleaner because as Frank described, it wasn't quite grouping as good as it had been. Saturday at the range my first group measured .806, with none of the bullets touching. Normally this gun shoots around half inch. I was a little concerned about what I might have done to it. The second group measured .730, however three of the rounds were in a nice tight group with all holes touching. The next three groups measured .322, .344 and .379. I'd never gotten three groups in a row in the .3s with this gun. In fact out of five groups I'm lucky to get one in the .3s or even the .4s.

Any comments about why the first group was so big and the final groups were so tight? Could JB have gotten the barrel too clean and the first few rounds had to fill in the tiny imperfections before the accuracy returned?

I'm anxious to get back to the range to see it these groups in the .3s continue.

 

[Steve Blair]

I have several barrels that need 20 rounds after a thorough cleaning before they shoot optimally. Almost all of my rifles shoot better after 5 initial fouling shots.

If I see that a rifle is not performing as well as it once did and nothing else has changed, I get out the bore scope and inspect the full length looking for problems.

Glad to hear that JB did the job for you. It has also worked for me with stubborn fouling, particularly in factory or high-mileage barrels.

 

[xtightg]

JB saved my 243 win from being re-barreled.
Back to all touching at 100 yards. ;D

 

[Travelor]

I ahve a friend that when he gets a new gun, if it soes not shoot well, he will dip 5 rounds (bullets only of course) in JB and shoots one and cleans, etc., until he has fired al 5. He swears that this has helped his guns.

I have never tried this.

Compass Lake Engineering makes custom AR-15's for service rifle competition using Krieger and Douglas barrels. They recomend cleaning with JB every few hundred shots.

George

 

[fdshuster]

otter: My results are the exact mirror image of yours after a thorough cleaning with JB: the barrel then requires 5 to a maximum of 10 shots to again produce the usual small groups. I would never JB clean & then go directly into a match where the results "count".

 

[LHSmith]

otter: My results are the exact mirror image of yours after a thorough cleaning with JB: the barrel then requires 5 to a maximum of 10 shots to again produce the usual small groups. I would never JB clean & then go directly into a match where the results "count".

Same experience here......with factory barrels.......however with premium custom barrels, I find it takes a lot less ( usually 1 or 2) "conditioning" shots after JB or Iosso, once in a while you get a barrel where the first shot from a ultra-clean bore is right in with the rest of the group.
To me this confirms Otters conclusion about the need to fill-in those nooks and cranny's with copper and carbon in a factory barrel to bring back peak accuracy.

 

[SS427]

Appreciate the replies guys. I will be giving some of my other guns this treatment now.

 

[15Tango]

JB is awesome stuff. You think those initial fouling shots are interesting on paper you should see what they do through a chrono!

JB has really helped me out.

Wayne

 

[acloco]

Believe barrels are like women, have to learn what each individual likes and dislikes.

My 300 win mag takes 9 to 11 shots to settle in after a good cleaning. After that, groups are always half moa, regardless of yardage. Also of note with this rifle, don't look at the 100 yard groups with 208 gr AMax's...it will be 1.5". Start looking at 300 yards on out.