SmallCaliberCentral

I have a Tikka T3 Stainless Steel Varmint (heavy barrel) rifle in .204. I have been reloading the Sierra 32 and 39 BK's behind RL10x (2.260 overall length) for several years, the rifle has always been a tack driver. All of a sudden the 39's are all over the target, including some keyholes, the 32's continue to shoot great. I clean the barrel religiously after shooting.
Any ideas on this? Any feedback/comments on this issue would be appreciated.

How many rounds do you have down the barrel? When my last barrel went south it too started to tumble the 39rs. Might wanna have someone look at the throat with a bore scope.

Probably around 2000-2500, it's made a few trips up to Cedarville.

What have you been using to clean the barrel? Have you used any aggressive cleaners such as JB's lately? I second the idea of using a borescope to look at the barrel.

Look at the tube. If it has been shooting great and suddenly opened up I third the motion to get the barrel bore scoped because with the way components are now why keep wasting the $$$ for fruitless cause.

HTH

I use Shooter's Choice followed up with BoreTech C4. I'll take it in and have the barrel checked out, thanks for the replies.

I do agree with previous posters. I am not familiar with Bore Tech C4. Is this product a copper solvent? Another question I have is, do you shoot this rifle HOT? It is really easy for a lot of people shooting in the rat field, to let their barrels get TOO HOT, myself included at times! This will shorten barrel life too. It does sound like you are getting close to the end of barrel life. Also you might try seating the SBK's a little longer and see what happens. You just might get one more season out of your barrel. Rat season is already here, and you may not want to take this rifle out of action right now.

The Bore Tech C4 is a carbon remover. After the initial cleaning with Shooter's Choice, the Bore Tech typically shows that Shooter's Choice did not get get all of the carbon. I will probably try Sweet's 7.62 and see how the patches come out, in addition to getting the bore scoped. As I first mentioned, the SIerra 32 BK's still shoot great in this rifle. As you noted, the action in the rat field's certainly will warm up the barrel, this one has been there. I usually alternate shooting three rifles in order to let the other's cool down.

My question here is, why use 2 different carbon cutting solvents?
You need to be using a copper solvent to eliminate copper build-up. Shooters Choice will eliminate some copper fouling, but is meant for carbon cleaning mainly. Sweets 7.62, as far as I know is a copper solvent. My personal choice is CR10. With that many rounds down the tube, and not using a copper solvent, did you not notice a loss of accuracy, with either bullet?

Finally got a look down the barrel with a borescope, appears copper fouling is the culprit. I had assumed (and after what i had read) that the Shooter's Choice would take care of the copper, not so, especially after I took some CR10 to the barrel and many blue patches later. Will get out this weekend to try it out.
Thanks for the replies from everyone.

That has to be a relief knowing the barrel is not shot out.

I have about 3600 rounds down the barrel of my 204 and it is still going strong.

Hopefully you are using nylon brushes with the CR10. Any copper solvent worth its salt, will start destroying a brass brush, and continually show up as copper on your patches. Sounds like are going in the right direction. Great thing about 204 forum, most all of us here are willing to help each other with our problems. There is a great wealth of info from our fellow members. We all make mistakes at times, but hopefully learn from our experiences.

In addition to using the CR-10 on that copper fouled barrel as Kevin suggests, I'd also suggest some JB Compound on a barrel fouled that much. Use an old bronze brush, then wrap it with a patch soaked in your SC solvent, then smear on the JB and short-stroke it in the barrel a few hundred laps, keeping it wet with both solvent and JB.

In place of the JB, and actually better is Holland's Witches Brew.....THAT stuff will really get the copper out, and get it out to bare steel. It was designed by both Darrell Holland and Chris Ditcher of Pac-Nor Barrels. Highly recommended.

After repeated scrubbing, this method will remove copper from even the most fouled barrels, and get them back to shooting as they should.

Thanks for all of the advice from the experienced shooters on this forum. I'll have an idea how the cleaning went after I shoot it this weekend, might be trying Rick's recipe next if I am still having issues. Need to get this rifle back on track for an upcoming trip to NE CA to visit skippy. Will alos be taking my newest addition along, a 20 VT in a rechambered CZ 527, turning into one of my favorites.

In addition you can wrap a piece of cloth called "Lead Away" around you brass jag and scub the barrel. If your gun is blued, DO-NOT rub on the blueing because it will come off.