Difference between copper plated and copper jacket bullets?

[jays]

What's the difference between copper plated and copper jacketed bullets?

[bladeracer]

What's the difference between copper plated and copper jacketed bullets?

Copper plated bullets are basically cast lead with a protective coating.
Jacketed bullets are soft lead encased in a hard copper shell.

[Turkle]

Jumping in... difference between cast lead and soft lead?

[juststarting]

Hard cast, not cast lead. I think it boils down to velocities you can shoot them at?

[bladeracer]

Jumping in... difference between cast lead and soft lead?

None.
I mean't a cast lead bullet dropped from a mould as opposed to lead poured or swaged into a jacket.

[bladeracer]

Hard cast, not cast lead. I think it boils down to velocities you can shoot them at?

Yep, hard cast refers to the alloy used and/or heat treatment to allow higher velocities without excessive leading, and/or better penetration of game.

[Oldbloke]

Difference is this
Copper plated or washed as sometimes used is simply electroplated, only a few microns thick. Only there for good looks. Is effectively just a lead projectile

Copper jacketed is: The jacket is made from sheet copper, perhaps 10 or 15 though of an inch thick, (sometimes thicker) then the lead is "swaged" or pressed into the jacket. Or perhaps the reverse order.

This one is jacketed.

Hornady.jpg (4.3 KiB) Viewed 5200 times

[Oldbloke]

Difference is this
Copper plated or washed as sometimes used is simply electroplated, only a few microns thick. Only there for good looks. Is effectively just a lead projectile

Copper jacketed is: The jacket is made from sheet copper, perhaps 10 or 15 though of an inch thick, (sometimes thicker) then the lead is "swaged" or pressed into the jacket. Or perhaps the reverse order.

This hornady interlock is jacketed.

Hornady.jpg (4.3 KiB) Viewed 5199 times

[brett1868]

I'll have a crack of combining all the info in 1 post....
Copper Jacketed as Oldbloke points out consists of a copper cup punch from copper alloy sheet into which a lead slug is inserted before being shaped with a series of dies (swaging) They originally developed jacketed bullets to overcome the limitations of velocity with lead. A lead bullets fouls rifles barrels and increases fouling exponentially with velocity meaning that as velocity increased barrels had to be cleaned more often which was not an ideal situation to be in when trying to shoot the enemy or practical for use in machine guns.
https://www.youtube.com/watch?v=Hkr1NS7bEUU

Copper Plated / Wiped / Coated (same thing) is generally done via electrolysis to deposit a very thin layer of copper. The reason behind this is mainly for lubrication and it's just thick enough to allowing slightly higher velocities than plain uncoated lead. Lead needs to be lubricated to reduce fouling, older style lubes were a wax/grease type but that isn't conducive to mass production. Newer style coatings using polymers or 2 pak style paints are popular but require multiple applications and drying time between coats so the next big thing was copper plating as it was a single application and thousands of projectiles could be plated very quickly in one application with minimal drying time.

Cast lead / Hard Cast lead - Lead hardness can be measured in Brinell units (HB) and depending on the use of the projectile you may want a slightly harder projectile for use in say a rifled barrel to reduce lead fouling where as in a smooth bore gun you can use a softer lead. Hardness can be controlled by "Alloying", mixing lead with small amounts of Antimony and or tin to achieve the desired Brinell hardness. I think Noisydad does a lot of casting and maybe he can add more info if required.

[juststarting]

How does gas checking come into this equation and how is it compared to other fouling reduction methods?

[Lorgar]

I'm by no means an expert on this, but my understanding of gas checks is they're only useful when you start to drive cast bullets faster.

With too much *bang* behind them, heat and gas damage the bullet and increase fouling.

The stronger gas check at the base lets you drive the bullet faster without the deformation and fouling you'd get at higher velocity without one.

That's my understanding.

[in2anity]

Raw lead has a brinnell hardness of ~5 bh. Hard cast lead is usually in excess of 15 bh (there's no standard so it's really up to the manufacturer's discretion/marketing strategy). Gas cutting will occur on both of these at certain pressure levels. Obviously the softer the lead, the lower the pressure needs to be to avoid gas-cutting. Copper gas checks mitigate this problem by sealing the base of the projectile, so you can push lead faster (without gas cutting occurring). Lubing will also help mitigate gas-cutting.

Then comes fouling; all lead will foul badly if you push it too hard. Again, the harder the lead, the faster it can be pushed before leading occurs. This is where coating and lubing also come into play - both help prevent leading. Coating is predominately for preventing leading, whereas lubing is both preventing leading and a gas sealant.

This is an extremely complex subject - but also a very interesting one

[bladeracer]

Raw lead has a brinnell hardness of ~8 bh. Hard cast lead is usually in excess of 15 bh (there's no standard so it's really up to the manufacturer's discretion/marketing strategy). Gas cutting will occur on both of these at certain pressure levels. Obviously the softer the lead, the lower the pressure needs to be to avoid gas-cutting. Copper gas checks mitigate this problem by sealing the base of the projectile, so you can push lead faster (without gas cutting occurring). Lubing will also help mitigate gas-cutting.

Then comes fouling; all lead will foul badly if you push it too hard. Again, the harder the lead, the faster it can be pushed before leading occurs. This is where coating and lubing also come into play - both help prevent leading. Coating is predominately for leading preventing, whereas lubing is both leading prevention and a sealant.

This is an extremely complex subject - but also a very interesting one

Gas checking the bullet also helps minimise the leading as it scrapes the bore.

[Chickenhawk]

Raw lead has a brinnell hardness of ~8 bh.

Aaaah, the old Brinnell hardness, something we're all familiar with

[in2anity]

Raw lead has a brinnell hardness of ~8 bh.

Aaaah, the old Brinnell hardness, something we're all familiar with

Wow did i make some mistakes when I first started shooting lead. My initial reasons for shooting lead were simply to cut costs, but now the subject absolutely fascinates me - I love shooting lead. Shooting and reloading lead has taught me so much more than I would never have normally been exposed to.

[Joom]

Mods said they might do a dedicated black powder and casting forum soon