How to stop cold bore shift?

[Earnhardt]

Jump up and down…and fart twice…that fixes alot of things.

(Yes, that's a joke)

 

[Ol' Red]

Jump up and down…and fart twice…that fixes alot of things.

(Yes, that's a joke)

I think that is to get rid of stomach cramps, but it could cause a cold bore shot if not careful.

 

[Jeffrey Van Zandt]

I'm getting cold bore shifts in the 300 Win Mag, it has some fire cracking in the throat, but not much. Using H4831 and 200 Accubonds for big game hunting, Cold bore is an inch high at 12 o clock, and remaining rounds are in a group an inch right and low at 2 o clock. Happened on three sessions when testing. How to I stop this cold bore shift?

dry fire fo a bit may be 10 dry fire then shot most cold bore is cold shooter and do not strip all the copper out when cleaning no cleaning till over all group opens up.

 

[Laelkhunter]

Interesting I might have to try that.

Greg Tannel sells a colloidal graphite solution for this purpose. It is extremely fine graphite suspended in a solution that evaporates after you push a patch through the bore before firing your first shot. The concept is the graphite fills in the cracks and voids in the chamber/leade/barrel and prevents that first shot from being "out of the group".

 

[Beluebow]

Captain Obvious here...Have you tried zeroing for your cold bore shot? Typically, on a fouled bore the first shot will have a higher velocity and reflect that on target. In my experience a fouled cold bore is more predictable than a clean cold bore. A clean barrel cold bore will typically go low. "Every barrel is different" so there is no hard and fast rule.

Greg Tannel sells a colloidal graphite solution for this purpose. It is extremely fine graphite suspended in a solution that evaporates after you push a patch through the bore before firing your first shot. The concept is the graphite fills in the cracks and voids in the chamber/leade/barrel and prevents that first shot from being "out of the group".

Same as NeoLube#1/#2 or Lock-Ease. I think Kroil makes a product that is similar called Kroil Penephite that may work in a similar fashion. But I haven't had the opportunity to test it yet.

 

[338 dude]

 

[Stadoc]

View attachment 630547

What rock have I been hiding under that I didn't know about these products

 

[FireFlyFishing]

Do you dry fire before shooting a string? Give that a shot…pun intended.

 

[Laelkhunter]

Jump up and down…and fart twice…that fixes alot of things.

(Yes, that's a joke)

I don't know about this advice. At my age when I fart, sometimes I have to change the underwear. Not so sure about the jumping up and down either unless I can hold onto my walker. You youngsters can give it a try.

 

[Horse1]

Jump up and down…and fart twice…that fixes alot of things.

(Yes, that's a joke)

Can you please define precisely how many jumps and at what point in the jumping phase the posterior emissions are to occur?

 

[340 in Va]

The late JE Customs had a post here I saved. We all miss him. Front first, 20 in lbs, rear, repeat going up by 20 in lbs. Since you have pillars, go to 65 in bls. Check after a few rounds

Thanks, good info, printed a copy to put in shop.

 

[Hugger-4641]

I had an Ar-15 that had a similar issue, but just the opposite. It shot the cold bore shot about 2" low and left and then shot a 1-1/2 MOA group about 1" to the right. Chronograph showed the cold bore shot was over 100fps slower than subsequent shot and the barrel continued to speed up slightly for the next few shots. I tried loading a cold bore rd with a grain or so more powder and it did tighten up the vertical some but never fixed the left/right dispersion. Wish I'd known about the graphite trick, I would have tried that, but I traded off that gun.

 

[TackDriv3r]

Dropped the 200 Accubonds, and went back to my old load with 180 Accubonds, did not get the cold bore shift today, cold bore in the same group with the remaining shots. I'll check again another day to confirm.
I did retighten the action screws yesterday as well.

 

[RYEWSKY25284]

I would try a couple of wet patches of Lock Ease graphite powder. I learned the trick from hall of fame bench rest shooter Speedy Gonzales and have had good luck with it minimizing cold clean bore shift in center fire. It also works well on match 22 Rimfire barrels.

Great idea. It can be found on.: YouTube /

Barrel cleaning by Speedy (Hall of fame BR shooter)
Originally posted by, Erik Cortina.