FMJ/plated?
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Make a lead bullet and add a thin copper layer, plated bullet.
Make a copper jacket, squish into it a lead core, fmj.
FMJ tends to be a much thicker which allows it to withstand higher rotational velocity.
For me, and speaking in general terms, I find plated to be less accurate.
Make a copper jacket, squish into it a lead core, fmj.
FMJ tends to be a much thicker which allows it to withstand higher rotational velocity.
For me, and speaking in general terms, I find plated to be less accurate.
Plated was a way to appease the ranges that didn’t allow exposed lead ammo. IMHO
Dale Gribble
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@JimB answered the question...
I think the exception to this is Speer’s line of TMJ (total metal jacket) projectiles. IIRC, the copper jacket on the base of the bullet is the same thickness as the rest of the jacket.
I cannot speak for their line of TMJ handgun bullets, but their .224 75gr TMJ performs great.
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Speer TMJ handgun bullets are plated, I believe all Speer handgun bullets are, but it is much thicker than most bullet plating.
FMJ refers to traditional cup and core as JimB described.
For the purposes of range regulations/rules in my limited experience plated is treated as FMJ. For the purposes of reloading it's debated some, but generally agreed that you shouldn't load max jacketed bullet loads under most plated bullets. Performance wise plated usually isn't quite as accurate.
Cost wise, I think powder or polymer coated is the way to go, especially if your only reloading for handguns.
I shoot a lot of plated bullets. Generally speaking, plated may not be as accurate as FMJ, but that isn’t to say that all FMJ will be more accurate than all plated. I’ve had some plated loads that have been very accurate.
The Speer TMJ are thick plated. If you call Xtreme and ask them about load data for their plated bullets, they will say to use the Speer TMJ load data, and I have found their data to correlate closely to my measured results.
One of the most accurate loads I’ve had for 357 mag were with TMJ bullets.
The Speer TMJ are thick plated. If you call Xtreme and ask them about load data for their plated bullets, they will say to use the Speer TMJ load data, and I have found their data to correlate closely to my measured results.
One of the most accurate loads I’ve had for 357 mag were with TMJ bullets.
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The basic answer is above, No, they are not the same. And as such,, can't be loaded to the same velocities as jacketed bullets.
In general,, most plated manufacturers suggest loads similar to cast bullets,, or MAYBE a little higher.
I shoot some plated,, as well as powder coated bullets a lot. Currently enjoying some 100 yd shooting in a .357 Maximum, at 100 yds with a powder coated cast bullet. 4"-5" groups are fun,, and running about 1200 fps.
Owning a range,, I get to see & recover a lot of fired bullets. Many copper plated bullets will show signs of the plating partially off the core bullet,, or even completely stripped off. Yet the powder coated bullets,, often appear to almost reloadable.
Copper jacketed bullets are a different design. It's a copper jacket, and a lead core (mostly).
FMJ stands for Full Metal Jacket.
In general,, most plated manufacturers suggest loads similar to cast bullets,, or MAYBE a little higher.
I shoot some plated,, as well as powder coated bullets a lot. Currently enjoying some 100 yd shooting in a .357 Maximum, at 100 yds with a powder coated cast bullet. 4"-5" groups are fun,, and running about 1200 fps.
Owning a range,, I get to see & recover a lot of fired bullets. Many copper plated bullets will show signs of the plating partially off the core bullet,, or even completely stripped off. Yet the powder coated bullets,, often appear to almost reloadable.
Copper jacketed bullets are a different design. It's a copper jacket, and a lead core (mostly).
FMJ stands for Full Metal Jacket.
No....
Five types of projectiles:
• Cast
• Plated ( over a core )
• Powder Coated ( over a core )
• Swaged Jacket " FMJ" ( over a core )
• CNC Machined Billet
Cast is simply that. Liquid lead poured into a mold. Generally, the better quality ( precision ) molds yeild better product.
Plated is short for Electroplated. Cast lead projectiles are electrically charged and sprayed with liquid copper in a specialized process. There are varying degrees of quality in plated bullets. Plated projectiles can not be pushed as fast as a jacketed bullet. Simply because the plated projectile is softer. The plating process is somewhat complicated by gravity. Liquid copper can "puddle" if the application process is not carefully controlled. We have spun plated projectiles in a CNC lathe collet and checked diameter runout. We have found plated projectiles with .0009" - .0015+" of runout. A "high" spot on a plated projectile can cause accuracy problems when they leave the barrel at tens of thousands of RPMs. Sort of like a tire out of balance.
Powder Coated (PC) are cast projectiles that have been coated by the powder coating process.
PC coatings are hard, durable, and viable in firearms projectiles. As long as the mfg and the coating process are controlled in a quality manner, they seem to do well for plinking and practice.
Swaged projectiles have a thin, precision sheet of copper ( or brass ) drawn over a precision lead core in a forming/swaging die.
This process produces a durable, precision, projectile that can generally be pushed faster than cast, plated, or coated. This process also lends itself well to mass production of precision components. Some of the best quality precision jacketed handgun projectiles are from Montana Gold. They use a brass jacket instead of a copper jacket. Brass is harder than copper, it "bites" the rifling harder. Sealing is supurb with these.
CNC Machined billet projectiles are the ultimate in precision and performance. Projectiles are turned from billet round bar of copper, or, brass. Modern CNC Swiss type turning machines have made ultra precision medical grade volume manufacturing possible. The CNC turned projectiled can be pushed harder than any of the above types, and the consistency between projectiles is amazing. They generally have less than .0002" runout.
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georgel
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The important part is that load data is not the same. Plated data is generally closer to cast and regularly maxes out at around 1100fps before the plating will strip. But, some manufacturers produce "heavy" plated to handle higher velocities. Consult the company. Also, be aware that low pressure pipsqueak loads can cause the plating to stick in the barrel and strip from the bullet. The core travels out from momentum, but the plating stays, blocking the barrel. Generally, want to stay above 800fps.
You can usually score a plated bullet with your nail, if that's an indicator to you of it's hardness. That's the old school Brinell test.
You can usually score a plated bullet with your nail, if that's an indicator to you of it's hardness. That's the old school Brinell test.
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Yes.
Plating is only as hard as the material it is applied to. Liquid copper sprayed on lead is not much harder than raw lead. The plating is micro thin.
I suspect the "heavy" plated projectiles are the ones most prone to being coated "out of round". They have more liquid copper material that can "run" & "puddle".