Dirty Barrel

[BZR]

Can someone explain to me why my factory rifle shoots better groups dirty vs when it is clean?

Clean I am lucky to get a 1" group at 100 yards once I have 10-15 rounds through it the grouping comes together very nicely!!

Cheers
BZR

 

[fdshuster]

BZR: Just another one of those mysteries of life, I guess. I have an older Remington 700BDL, 222 Rem. and as seen with my "Hawkeye" the barrel is far from nice looking, but as you have experienced, the dirtier the barrel gets, the smaller the groups become. First 5 at 200 yd. will just barely make moa, and after 40 or 50 rds. fired I'm looking at 3/4" to 1" max. On the other hand, my Hart, Shilen & Krieger barrels must be cleaned every 20 rds. or so to produce the typical 1/4 moa groups.

 

[tenring]

Carbon and copper build up make for a tighter seal in some, not all, barrels. But this will reach a point of diminishing return somewhere down the line. When those tight groups open up again, better swab the tube.

 

[fdshuster]

tenring: I suspected what you said in your response, but hesitated to post it, since it was only my opinion. It's kind of nice though to take just such a rifle and go out and shoot the thing, without being concerned about keeping the bore squeeky clean, and still have it produce good groups & nail the occassional g'hog. That is the main reason there are several rifles that I will not re-barrel 'til the groups start to open up to an unacceptable level. Also agree with your thoughts about cleaning being eventually req'd. In the case of the 222, 40 to 50 rds. is approaching the limit.

 

[BZR]

Now the hard part is figuring out when to clean and even worse...

Once it is clean I will know my first dozen shots are only good for getting the barrel dirty again...

Thanks for the replies!

 

[kelbro]

I have an old 243 barrel that acts like that. I have found that running a boresnake,with the brush removed and a couple of drops of CLP on the head) through it gets it back in shape without needing 10-15 foulers. Clean but not 'too clean'.

 

[BZR]

That is a great idea! I went shooting today and I really didn't want to clean it but know I need to.

I will give the bore snake a try. How many times do you run it through like that?

 

[gatewood]

You never said but are you shooting moly bullets? Thats a typical moly reaction as the moly gets worked back into the bore after you clean. thats why I quit with moly in a ppc i tryed it in. it took at least 15 fouling rounds!

 

[BZR]

I am not shooting moly bullets...

I understand why people shoot them but it seems that you will never have two shots the same when you use them... What is the point in that?

 

[kelbro]

That is a great idea! I went shooting today and I really didn't want to clean it but know I need to.

I will give the bore snake a try. How many times do you run it through like that?

Usually every 10-20 rounds.