Cupronickel use?


Why is cupronickel no longer used as a jacket material as much as it was many years ago? Seems as if it was a common material during the first half of the 1900’s. I’ve heard that it could cause bore fouling that was very difficult to remove. Is this why it fell from favor?



Cupro-nickel can leave a very heavy and difficult to remove fouling, especially with the higher velocities. Evidently it wasn’t a serious problem in the U.S. with the .30-40 cartridge, but with the .30 M1906 loading serious metal fouling became an increasing problem. Removal required stern means, including ammonia dope, which was potentially a worse problem than the fouling if incorrectly employed. Jack


Another reason might be that over the years, nickel has become increasingly expensive…at about $10 a pound now…as opposed to copper at about $3 - $3.50…

I agree with Jack also that the copper/nickel alloys caused nasty barrel fouling…

Also. I seem to remember that when a copper alloy was used in the early days, jacket stripping was a problem, leading to the use of the nickel to create a harder jacket material…



CN bullets were indirectly responsible for problems far more serious than the damage done by improper use of ammonia dope. Army guys thought that the fouling problem could be lessened or eliminated by lubricating the outside of the bullet, so it was routine for the well equiped shooter to carry a small can of grease in which he dipped his bullets before loading. If a little grease was OK, a lot of grease was even better. When locking lugs started shearing and some rifles blew, the culprit was found to be grease that was getting onto the case and inside the chamber. This increased chamber pressure to danergous levels. The use of grease was prohibited but it didn’t stop the practice completely. In 1922 Frankford Arsenal began loading National Match ammunition with a new GM jacketed bullet and the CN fouling problem was history.

Randy - I wonder about copper being too soft and stripping. The well known Newton and Barnes bullets had jackets of pure copper and they didn’t seem to be a problem. Today’s modern hunting bullet designs include many made of solid copper. Maybe those early bullets had jackets that were simply too thin??



Yes, Ray…
I thought of that also…many bullets for many years have had jackets of copper alloys and no problems, but back in the day, I seem to remember FA having problems, and I’m not sure why…a good research project, I suppose…



I’ll go along with nickel fouling being hard to remove. We used to get old .303 ammo with nickel bullets and its very hard to get fouling out of a barrel. There used to be a cleaner called Motty Paste which was a form of jewellers rouge which had to be used along with a lot of elbow grease to scrub it out.