copper on barrel wear?

[clockwork65]

Years ago I recall guys talking about how mono copper bullets fouled barrels much quicker than bonded, etc. I'm assuming, given the current popularity of monos, that this is no longer the case due to new tech/design?

 

[jmr40]

I doubt if that were ever a real problem. All standard bullets have copper jackets. The barrel doesn't know if it is a copper jacket or solid copper. As near as I can tell some rifle barrels foul with copper more easily, but I don't see the bullet as the cause.

 

[std7mag]

It's got to shoot paterns instead of groups for me to clean the copper out of my barrel.
Carbon is a different story.

There are several myths from the bad ole days that people are finding out now were unjustified.

 

[Mobuck]

Early "copper" bullets were quite soft and tended to smear off in even moderately rough bores. Then the "copper" was made harder to lessen this problem inciting some to claim excessive bore wear. Considering that most "copper" bullets were designed primarily for big game hunting(at that time), it would be surprising if most shooters fired enough of the "harder" copper bullets to make any diff. Early "copper" bullets also tended to raise chamber pressures requiring load adjustments(and some "monolith" bullets still do).
I suspect that a lot of the copper we find left in rifle barrels is on the trailing edge of the lands and really has little to do with overall accuracy until a truly significant amount has built up.

 

[Scorch]

All standard bullets have copper jackets.

Not really. Most have jackets made of "gilding metal" a copper alloy similar to brass, which is 95% copper and 5% zinc. Gilding metal fouls much less than copper.

Pure copper was responsible for the early Barnes bullets fouling barrels so much 20 years ago. Some of the fouling issues were alleviated by adding grooves to the bullets to reduce surface area of the bullet in contact with the bore, and reduced even further by using gilding metal in some other bullets. I don't know if any company uses straight copper any more.

 

[reynolds357]

I doubt if that were ever a real problem. All standard bullets have copper jackets. The barrel doesn't know if it is a copper jacket or solid copper. As near as I can tell some rifle barrels foul with copper more easily, but I don't see the bullet as the cause.

The alloys of TSX and jackets are different, but I think what causes the notable fouling is the higher velocity of the solid bullets, Tsx, Ttsx, Gmx, etc. Most move way down in weight when they go to a Tsx. With that weight drop comes velocity and more fouling.

 

[Red Devil]

Harder Materials - will cut (wear) softer materials.

Barrel Steel - is considerably harder than copper or gilding metal.


What erodes bores is Ablation - the hot gasses vaporizing the surface of the hot/soft barrel steel, usually at a 3:1 throat/muzzle ratio.

The hotter/softer the steel - the more rapid the erosion.




Red

 

[Art Eatman]

Ablation occurs at the throat, but since accuracy degrades with that, barrels are replaced long before any ablation occurs "downstream" from the throat.

Shooting is lapping, just in normal usage. Whether lead or gilding metal, the bore gets polished.

 

[LineStretcher]

Ablation occurs at the throat, but since accuracy degrades with that, barrels are replaced long before any ablation occurs "downstream" from the throat.

Shooting is lapping, just in normal usage. Whether lead or gilding metal, the bore gets polished.

Perfect Art. A new barrel will foul more until it's groves (not lands) are sweetened. That's a little old school term for the somewhat inaccurate term of today "broken in".

 

[Red Devil]

Ablation occurs at the throat, but since accuracy degrades with that, barrels are replaced long before any ablation occurs "downstream" from the throat.

Shooting is lapping, just in normal usage. Whether lead or gilding metal, the bore gets polished.

As stated - ablation also occurs at the muzzle, at roughly a 1/3 rate of the throat.




Red

 

[stillquietvoice]

Sometimes it is the bullet. When I got my rem 700 in 7-08 I fired factory rounds from hornandy, privy, federal and Winchester then reloaded several different manufacturers bullets in 139-140 gr. Weight with no issues. Bought rem 140 corelockt and after only 15 rounds my bore looked like a copper mine, it took a week to clan it out. I've never shot them again and have not had an issue like that since