Weatherby copper fouling

IK-NWhunter

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I have a 257 Wby Mag and a 300 Wby Mag and have noticed some severe accuracy issues (2-3x MOA) I chalk up to copper fouling after sending about a dozen rounds downrange in the 257. The 300 is brand new, so I'm still learning how it responds. I know a lot of you out there have more experience shooting and reloading than I do. I'm wondering if anyone else has had this experience with the Weatherby cartridges and can offer some guidance or advice? I really like both rifles and should probably invest in some reloading equipment and a chronograph to get the most out of them.

Although I would prefer the shoot accubonds given the superior ballistics profile, I've found the 100gr barnes TTSX seems to work really well in the 257 with slower fouling. The barnes website states the lateral grooves on the side of the round minimize fouling because it gives displaced copper somewhere to go. Should I expect the same for the 300 Wby Mag? Does increased velocity equate to faster fouling? The cartridges for sale on the Weatherby website have higher listed muzzle velocities than any other manufacturer I've found, i.e. Nosler, Hendershots, etc.

Also does the manufacturer of the rifle itself make a difference? The 300 is a Weatherby Mark V while my 257 is a Remmington 700 CDL.

What methods work best for cleaning your fouled rifles and how often do you clean when shooting at the range?

THANKS!!!
 
I own both .257 and .300 in Mark V Weatherby models and have used both exclusively (with the exception of my phenomenally accurate and deadly Remington XP100 7mm08 'Bear Slayer') for many years and both have performed flawlessly, accurately and without any problems or malfunctions. I use Weatherby ammunition exclusively and my maintenance is usually limited to an annual 'spring cleaning'. All three Mark V rifles were purchased new.
 
Clean the rifles with a copper cleaning solvent until they are clean. Then shoot them again and see how they group. Some rifles especially factory barrels take a few shots to settle in on a clean bore.
The 257wby and 100gr TTSX is a great combo!
 
I don't know how much difference it makes but the jacket material on the Accubond and TTSX are different. TTSX is supposed to be solid copper. Accubond is gilding metal. I would imagine what is happening to you happens in other cartridges too.
 
Have dozens of Bees and never had that problem after 12-15 rounds if anything the opposite. After I give them their annual copper removal cleaning I have 1 300 that takes 12 rounds to foul enough to get best accuracy (1/2moa). Barnes bullets seemed to foul faster and cause accuracy issues but that was still after at least 20-30 shots and could be very accurate when clean barrel. I no longer shot Barnes bullets. I haven't found a weatherby mark v that wouldn't shot moa, might take some effort with ammo and bedding but always got it accurate if barrel was in good shape. Handloading bees pays for itself fast, if you buy ammo buy nosler or weatherby not Hornady or rem crap
 
I don't understand the whole "gotta get the copper out" thing.

I have never cleaned the copper from any of my rifles. Just some Hoppes #9 to get the carbon out.

If your groups are opening up after 12-15 rounds i'd suggest looking elsewhere.
 
I don't understand the whole "gotta get the copper out" thing.

I have never cleaned the copper from any of my rifles. Just some Hoppes #9 to get the carbon out.

If your groups are opening up after 12-15 rounds i'd suggest looking elsewhere.

Eventually, you will understand the copper "thing".
 
I don't understand the whole "gotta get the copper out" thing.

I have never cleaned the copper from any of my rifles. Just some Hoppes #9 to get the carbon out.

If your groups are opening up after 12-15 rounds i'd suggest looking elsewhere.

Copper fouling is definitely an issue with many rifles and especially rough bores. The issue is group size will open when to much copper is built up in the rifling.
 
I read your question fairly quick so I might not understand your problem but I wouldnt jump to the conclusion that copper fouling is the problem. Individual rifles prefer their own bullet. Even rifles that are from the same manufacturer and one serial number off can shoot differently. If youre shooting .5in groups then open up to 2xMOA after 300 rounds then it might be fouling.

If you are shooting under 400 yards I wouldnt put too much credit into ballistic coefficients.

I would buy some different ammo brands and test them before investing in reloading equipment.
 
I don't understand the whole "gotta get the copper out" thing.

I have never cleaned the copper from any of my rifles. Just some Hoppes #9 to get the carbon out.

If your groups are opening up after 12-15 rounds i'd suggest looking elsewhere.

You will. And when it does you will be scratching your head thinking you burned a barrel out. Took me three days to get one of my rifles un-fouled. Thats when I learned about having to get the copper out thing, unfortunately it cost me a nice 6 point bull elk and three days being rifle-less during elk season. I now clean every 100 shots with a butchs bore shine.
 
Std7mag

What kind of accuracy are you getting? I'd be interested in what the patches might look like if you ran some copper solvent through one of the rifles only cleaned with hoppes.
 
I'm not sure my Weatherbys have more copper fouling than my other rifles, but I do know they get dirty quicker. My guess is that it's the keg of powder I'm burning with each shot more than the copper. I use the Montana Xtreme products and just clean more regularly.
 
Cahunter,

I'm still holding 0.72" 5 shot at 100 yards. Prone, bipod, rear bag. That with the PP2000 and 140gr. Berger VLD Hunting.
RL17 and 139gr. SST opens up to just under an inch. This is a factory Stevens 200 rechambered to 7mm-08AI.
Pencil barrel, plastic stock. Has about 4,000 rounds through it.
Time for a new tube, but only because the throat is worn to the point where i'm seating the bullets out too far for my liking.

BTW 7mm Rem Mag 2,00+ rounds, 257 Roberts unknown( bought used) estimate 1, 500 rounds.

Tomorrow is last hoorah for Stevens barrel. Shooting 600yard match with it.
 
Gotcha

Sounds like you have a great barrel and good use from it. Carbon build up is usually a factor that many people overlook also but routine cleaning usually takes care of that. Seems the more overbore calibers and dirty powders are more susceptible to carbon buildup also.

Good luck in the match! Will you be going aftermarket tube as a replacement?
 
Thanks!

The Stevens action is going to be a 250 Savage build that i already have a barrel for.
Planning on building a designated range rifle on a Savage Axis action. Again 7mm-08AI.
Torn between getting a heavy barrel from E.R. Shaw (local to me), or a polygonal from Pac-Nor.
 
Thanks a bunch everyone! I've had success using the extreme copper killer before, and currently use it every time I'm finished at the range with either of these rifles. It's working well enough to maintain MOA accuracy out to 600 yards. I'm going to try the Dyna-Tech kit Tjay suggested and see how that works. If all goes well I expect I'll be making the transition over to accubond rounds whenever I hunt outside of condor habitat!

I noticed some folks here seem to not know what I'm talking about when I refer to copper fouling issues. I have several other non-magnum rifles like 30-30 and 30-06 that never seem to have this issue. My understanding is that the Weatherby barrel/bullet tolerances are tighter than many other calibers and the pressures from there cartridges are fairly extreme, which leads to this issue. Interesting some people with Mark V's in these 2 calibers don't experience much fouling, or it happens slower than what I've seen anyway. I wonder if it's a difference between the factory barrel quality of Rem vs. Wby?
 
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