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I can't think of any reason why the bullets (alone) would be harder on a barrel. Some of the loaded ammunition using FMJ's might be.

Why do you ask? Where did you hear/ read that?

Cheezywan
 

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I'm no expert but I would say it depends on what the jacket is made of, "metal" as in "full metal jacket" is a broad term. If the jacket is steel then it would probably be harder on a barrel, if it is copper I don't see why it would be different than our hunting and target bullets. All the fmj bullets I've used were copper.:)
 

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All rifle bullets are jacketed in copper. The barrel doesn't seem to care what the tip of the bullet looks like as it never touches the rifling anyway. So no, FMJs aren't going to wear a barrel any faster than a hollow point, or a soft point.
 

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The Troll Whisperer (Moderator)
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a steel-core FMJ is probably a different matter, though.
 

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I'm no expert but I would say it depends on what the jacket is made of, "metal" as in "full metal jacket" is a broad term. If the jacket is steel then it would probably be harder on a barrel, if it is copper I don't see why it would be different than our hunting and target bullets. All the fmj bullets I've used were copper.:)
I've never heard of a bullet with a steel jacket...ever. I would think it would be incredibly dangerous if one were to be fired in any kind of firearm, as it would result in a radical pressure spike.

I have heard of solid copper bullets being harder on barrels because they do not have a relatively soft lead core that will "give" slightly if the bullet jacket meets any type of barrel constriction. Solid copper, or gilding metal, bullets have tighter tolerances than conventional jacketed bullets, which in turn have tighter tolerances than cast bullets: The more lead in the bullet, the more it will give as it is fired, making them somewhat of a safeguard against higher pressures.
 

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Broom-jm
Most comblock mil-surplus bullets are steel jacketed with a copper wash. Never heard of any wear due to the steel jacket, so I would say its a non-issue.
 

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The Hog Whisperer (Administrator)
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Yup. I've got some steel 6.5x55 surplus. I think there is a tin wash over the jackets, but they stick to a magnet.

Some European hunting bullets are mild steel jackets with a copper wash. Also old Norma .44 mag ammo was the same.
 

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I've never heard of a bullet with a steel jacket...ever. I would think it would be incredibly dangerous if one were to be fired in any kind of firearm, as it would result in a radical pressure spike.

I have heard of solid copper bullets being harder on barrels because they do not have a relatively soft lead core that will "give" slightly if the bullet jacket meets any type of barrel constriction. Solid copper, or gilding metal, bullets have tighter tolerances than conventional jacketed bullets, which in turn have tighter tolerances than cast bullets: The more lead in the bullet, the more it will give as it is fired, making them somewhat of a safeguard against higher pressures.

Most of todys big bore FMJ bullet do indeed have a steel jacket to prevent deformation with a guilding metals over the steel. They do tend to be hard on "old" British double rifle barrels that are not as thick as the barrels on more modern doubles. The "steel" jacketed solids have been know to break the barrel solder and seperate the barrels.
I see no problem with bolt or single shot style rifles
 

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Bullet jackets (US Military Manf) are copper jacket or CCGM (copper clad gilding metal) and the copper is approximately .006 thick so the rifling (approx .004" high wont cut through the copper and contact steel jacket so the theory goes but I have examined recovered projectiles fired at long range on military ranges and note the grooves in the bullets are rusted proving the jacket material was not necessarily all protective.

Foreign military ammo is not necessarily not so well engineered and is copper washed which means it is thick enough to keep the steel jacket from rusting readily but when fired the the steel jacket material contacts barrel rather quickly. Though it is soft material it will tend to wear the barrel with sustained shooting. I like to use pulled 7.62 COMBLOC bullets to break in new 30 cal barrels that have lots of tool marks left during manufacture and hopefully smooth them down. It will take several thousand rounds to have any major effect on barrel surface but a few early in the game is nothing.

LC Match bullets jackets have a higher hardness rating than commercial soft copper jackets and this is an advantage when you have a barrel in bad shape. The hard copper doesn't tend to deposit material on the rifling as does one with a soft jacket.

Next time you go to a gun show take a metal scribe that looks like a pen with a marking scribe on one end and a magnet on the other. Touch the magnet to bullets here and there and see which ones attract.

Most all the Russian ammo I have seen including 308 Win hunting ammo is steel jacket.

Beware of older 30.06 ammo (early 1900s) with cupronickel jackets and steel cores. They left massive amounts of jacket material in Springfield rifles. They were a bad scene for sure.

It actually takes a lot to damage a barrel with steel jackets as they are so soft. Case in point is I have a barrel that was button rifled and it looks like someone used a mill bastard file and a brick to cut the rifling. It is extremely rough so I decided to see if I could smooth out top of riflling. I turned some .300, .301 and .302 diameter bullets on lathe from oil hardening drill rod. Heated them up and quenched them in oil and shot about five of them getting bigger as I went. I kept running bore scope down barrel after each shot and to my great surprise even the .302 bullet did not affect the top of the rifling anywhere near what I had hoped.

I finally pulled the barrel and decided to wait till another time to make some .303 diameter bullets and try to smooth it up. This barrel took off massive amounts of bullet jacket material and accuracy was never better than 2.5" at 100 yards. Not any where near acceptable performance.
 
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