Terrible day at the range ! UPDATE

[garandman]

So went to the range today .... the last decent looking day for about 2 weeks to finalize some loads that had showed promise.

The 8 different loads I shot were all above 1" groups at 100 yd. Stuff that had showed potential for 1/4 to 3/8 of an inch.


This is on a new build with about 300 rounds down the barrel. Now doing post mortem it reminds me of about a 150 rounds ago that also had terrible groups.

After that I cleaned the barrel with copper remover and the accuracy returned so it got me to asking questions. (I usually clean the carbon fouling after every range trip)

Do fast twist 1 in 7 barrels copper up faster than others?

Is there a way to condition the barrel to minimize coppering?

Use bore paste/polishing the barrel common place in new barrels?

Flitz or JB paste?

Any other ideas ?

 

[JFrank]

Stop cleaning so much

 

[garandman]

Stop cleaning so much

Accuracy went away when I did that. It came back when I cleaned.

 

[Big Mc]

So went to the range today .... the last decent looking day for about 2 weeks to finalize some loads that had showed promise.

The 8 different loads I shot were all above 1" groups at 100 yd. Stuff that had showed potential for 1/4 to 3/8 of an inch.


This is on a new build with about 300 rounds down the barrel. Now doing post mortem it reminds me of about a 150 rounds ago that also had terrible groups.

After that I cleaned the barrel with copper remover and the accuracy returned so it got me to asking questions. (I usually clean the carbon fouling after every range trip)

Do fast twist 1 in 7 barrels copper up faster than others?

Is there a way to condition the barrel to minimize coppering?

Use bore paste/polishing the barrel common place in new barrels?

Flitz or JB paste?

Any other ideas ?

SS or CM barrel ??

 

[garandman]

SS or CM barrel ??

SS.

 

[JFrank]

If you have a good load I honestly believe it’ll shoot clean or dirty.

 

[garandman]

If you have a good load I honestly believe it’ll shoot clean or dirty.

With carbon, maybe. If the bbl is coppered up, I doubt it.

Still testing it tho.

The way it was described to me… if there are copper patches/smearing in the barrel, it will actually squeeze the Projectile and deform it slightly such that it flies out of round and group size opens

 

[JFrank]

Well
You asked for ideas, that’s mine.
Please report back when you figure it out.

Shoot Small
J

 

[garandman]

Well
You asked for ideas, that’s mine.
Please report back when you figure it out.

Shoot Small
J

Mostly I'm looking for the significance of the effect of copper in the barrel, how to deal with it and how to minimize it.

 

[golong]

With carbon, maybe. If the bbl is coppered up, I doubt it.

Still testing it tho.

The way it was described to me… if there are copper patches/smearing in the barrel, it will actually squeeze the Projectile and deform it slightly such that it flies out of round and group size opens

If the copper is not filling a void, then yes it is taking up room. Copper drags on copper, resulting in more copper. I have seen some pretty interesting results on the Labradar and on paper with barrels that were copper fowling. Warm (not hot) barrel with copper fowling was close to normal speeds with slightly exaggerated ES/SD. By shots 4 or 5, barrel is past warm and velocities would drop close to 75 fps on some shots. Still, if you pull out too much (clean out the voids) then you get almost the same - bullet is dragging going down the barrel to fill to voids.

So back to you question on twist, yes and no as far as I am aware. Fast twist with a light projectile, yes, it wants to form a hard carbon ring pretty quick. That ring then starts to crack and fill the cracks with copper. A real mess if you don't stay on top of it. Fast twist is mainly for heavier projectiles, but you can shoot a slower node with a lighter bullet as well.

What caliber we talking about with a 1:7? 22, 243, 264? What projectile? Velocity?

 

[garandman]

@golong .... THATS the info Im looking for

Its 224 Valkyrie.

The other thing that definitely happened today was SD's went wonky.

The barrel has been consistently giving me anywhere from 2 to 5 fps.

Today along with terrible groups SD's went up to the low teens.

Velocities are in the 2700 - 2900 range for 80.5 and 85.5 Bergers. AR- Comp powder.

 

[golong]

Yeah, based on your combo you should not be having problems. Guessing you got it warm early and started a carbon ring an inch or so past the OGIVE that is now cracking and filling up with copper. If you feel your patch grab at all there then you have one. I screwed up a 6 Dasher barrel early in the round count that way. Barrel turned into a high maintenance barrel, but I still got the full shot count out of it. If that is what you have, hopefully you are catching it early enough (I did not) to where you are able to get the entire ring out without drastic measures. I did not want to go to drastic measures, so I had to do semi-deep cleanings earlier than normal.

The 224 Valkyrie is a hardy barrel. Guessing you will be able to fix it given your low count.

 

[garandman]

@golong ... what cleaning techniques are recommended to get the carbon ring?

 

[gman47564]

I tend to agree with spj… if the load is good it should shoot good clean or dirty to a extent... if you had over a hundred or a hundred and fifty rounds down it it could go south on ya.. but it should hold good to at least a hundred rounds down it... it could be your barrel is still speeding up and it has sped up enough to get you out of your node...

 

[garandman]

I tend to agree with spj… if the load is good it should shoot good clean or dirty to a extent... if you had over a hundred or a hundred and fifty rounds down it it could go south on ya.. but it should hold good to at least a hundred rounds down it... it could be your barrel is still speeding up and it has sped up enough to get you out of your node...

I clean carbon every 50 - 75 rounds. But I hadnt cleaned copper in 150 or so.

 

[DirtySteve]

Who made the barrel? or did I miss that....?
If the barrel is coppering up fast you may want to use Tubb's Final Finish to smooth out the barrel.

I clean about every 150-200 rounds or so...

 

[K22]

With my Tikka 223 Rem, 8" twist, I've been shooting 55 and 60 grain bullets with excellent accuracy, groups under 1/2" at 100 yards. I've discovered at least with my rifle, that the lower charges of powder are more accurate with the faster twist for these bullets.

I clean every 35 to 40 rounds with a carbon remover first, i.e. Bore Tech C4, then with a copper remover, Bore Tech Cu+2. I use a bronze brush with the carbon remover. The key, I believe, is to not let the carbon and copper built up.

 

[garandman]

. I've discovered at least with my rifle, that the lower charges of powder are more accurate with the faster twist for these bullets.

Same here.

I clean every 35 to 40 rounds with a carbon remover first, i.e. Bore Tech C4, then with a copper remover, Bore Tech Cu+2. I use a bronze brush with the carbon remover. The key, I believe, is to not let the carbon and copper built up.

Agreed.

 

[LCazador]

I've seen similar problems like what yer' havin' and it's always turned out to be my choice of powder ! You can't believe what a maroon I felt like!

 

[garandman]

I've seen similar problems like what yer' havin' and it's always turned out to be my choice of powder ! You can't believe what a maroon I felt like!

Yeah, CFE turned out horrible. AR- Comp seems better. H4895 is next.