Thread: Dirty or Clean barrel?

Originally Posted by Magnus

I brought a tikka t3x chambered In 300 win mag, I took it to the range to dial it in at 200 yards. Started sending rounds down range and the first 10 were flyers all over the place, wasn't till about the 20th the group tightened up to1moa at 200yards which I was more then happy with.
Got it back home thought I'd to it a favour and give a a good cleaning and ended up removing the copper fouling from the barrel, decided to take it back to the range to check it with a different load and hello she's flying all over the place again till it gobbled up another 20 rounds and same again back to 1 moa at 200 yards. Now I just use a solvent that removes powder residue, only to ensure the corrosive component is taken care of and only clean the copper fouling out when accuracy starts to drop away.
Lesson learnt is copper equilibrium in the barrel is very important to accuracy.

The following vid is from a guy that does a heck of a lot of extreme long range precision shooting and explains the importance of fouling etc.

https://youtube.com/watch?v=_KRUAv3Byp4

Great link. Lays it out in detail. Thank you.