Are "JHP" ("jacketed" hollow point) bullets for reloading "jacketed" or "plated" ???

[valleyforge.1777]

I'm confused about some terminology (and the implications of that terminology for selecting load data):

Are "JHP" ("jacketed" hollow point) bullets for reloading "jacketed" or "plated" ???

I have a bunch of 9 mm FMJ from Montana Gold that are open (i.e., lead showing) at the bottom, and I am assuming that means what the label says, full metal jacket.

I think total metal jacket means that there is a metal jacket on the bullet that covers all surfaces of the bullet (is that correct?), although I've also seen TMJ bullets referred to as "plated" instead of "jacketed" so I am confused about that. Or, am I thinking of Complete Metal Jacket, CMJ, and is there any difference between TMJ and CMJ???

Then we get to HP bullets:
I have a whole bunch of Montana Gold 38/357 125 grain JHP bullets to load, and they have metal all around the bullet, including the bottom of the bullet. There's metal everywhere except in the hollow point cavity. They list them as "JHP", which I take to mean "jacketed" but are those really "plated" and anyway does it really matter for loading? I was going to use FMJ loading data for them with Titegroup since there is no published data specifically for these bullets and I thought they were "jacketed". Should I be using data as if they are plated, i.e., should I be using lead data?

 

[moxie]

Think of JHPs as sort of upside down FMJs, with the exposed lead on top instead of on bottom. They are jacketed.

Whether TMJs are jacketed or plated is an ongoing discussion, but I've always used jacketed data with them with good results.

 

[LiveLife]

Before ATK/Speer registered the term "TMJ" for Total Metal Jacket, some used TMJ to describe bullets that had jacketing/plating over the entire bullet. After ATK/Speer registered "TMJ", it now describes their plated bullets.

Montana Gold Bullets uses CMJ for Complete Metal Jacket which is a FMJ bullet with a disk that covers the exposed lead base.

I have a whole bunch of Montana Gold 38/357 125 grain JHP bullets to load ... I was going to use FMJ loading data for them with Titegroup since there is no published data specifically for these bullets and I thought they were "jacketed". Should I be using data as if they are plated, i.e., should I be using lead data?

Although Montana Gold jacketed bullets have brass colored jacketing instead of copper, they are jacketed bullets and I use jacketed load data with them. Although Speer Gold Dot bullets are plated bullets, the plating is thick enough to essentially consider them jacketed bullets and when a load data lists Gold Dot HP bullets, I use the load data for jacketed bullets.

Since HP bullets are longer than FMJ bullets (due to the cavity at the nose tip), HP bullets will often get seated deeper than FMJ bullets which will increase chamber pressures. When using JHP bullets, I would stick to using load data for JHP as FMJ load data often has higher start/max powder charges than JHP load data.

 

[Hondo 60]

I think total metal jacket means that there is a metal jacket on the bullet that covers all surfaces of the bullet

That's a common misperception.
Speer has trademarked the phrase Total Metal Jacket (TMJ).
It's just their version of FMJ

It may or may not mean the lead is totally encapsulated.

The difference between plated & jacketed is the process of getting the copper on the lead & the thickness of said copper.

A plated bullet is bathed in an electrically charged tank & copper is introduced.
One part is negatively charged while the other is positively charged.
I forget which is which. But opposites attract, covering the entire lead core..
The copper plating is as thin as .0005"

A jacketed bullet, has the copper wrapped around a swaged lead core & is therefore thicker than the copper on a plated bullet.

 

[Chief 0652]

I think of plated bullets as merely lead bullets which are less likely to cause lead fouling in the barrel. For reloading, I always use the lead loading data for plated bullets.

 

[Walkalong]

Using starting lead load data can result in stuck plated bullets. They have a lot more friction than lead.

Berrys

Plated bullets occupy a position between cast bullets and jacketed bullets. They are soft lead, but have a hard outer shell on them. When loading plated bullets we have found best results using low- to mid-range jacketed data in the load manual. You must use data for a bullet that has the same weight and profile as the one you are loading. Do not exceed mid-range loads. Do not use magnum loads.

Ranier

We, at Rainier Ballistics, recommend using lead bullet load data when loading our bullets. There is no need for adjustment when using lead bullet load data. Our bullets are jacketed using an electroplating process and are softer than traditionally jacketed bullets; hence the recommendation to use lead bullet load data.

If you only have access to traditionally jacketed load data, we recommend a starting powder charge directly between the listed minimum and maximum load, and you may use published load data found in reputable reloading manuals.

Rainer contradicts themselves with these two statements, and I can say for a fact some starting lead data will stick their plated bullets, especially long for the caliber bullets. They used to publish data and it was not starting lead data.


X-Treme

Load Info:
Our Copper Plated Bullets can be run at mid-range jacketed velocities or higher end lead velocities. We do not recommend velocities over 1500 FPS (Feet Per Second) and only a light taper crimp.
Any velocities over 1200 FPS we recommend either our Heavy Plate Concave Base or Hollow Point products for superior accuracy. We do not recommend velocities over 1500 FPS (Feet Per Second) and only a light taper crimp.
- All of our Hard Cast Lead Bullets are approximately 18 on Brinell, our Cowboy lead bullets are approximately 15 on Brinell.

Powerbond

Our proprietary plating process electro-chemically bonds the copper to the lead core. Our copper is thicker and tougher than other bullets...between 10 and 11-thousandths. Proper adhesion is continuously monitored and tested to ensure uniform, maximum bonding.

A thick copper plating and folks are pushing Powerbond bullets as hard as jacketed.

 

[ljnowell]

That's a common misperception.
Speer has trademarked the phrase Total Metal Jacket (TMJ).
It's just their version of FMJ

Thats a misconception too. Speers TMJ isnt a jacketed bullet at all. It is most definitely a plated bullet. They are very thickly plated, and are loaded with jacketed data, but the process of manufacture is most definitely plating.

 

[Chief 0652]

Thats a misconception too. Speers TMJ isnt a jacketed bullet at all. It is most definitely a plated bullet. They are very thickly plated, and are loaded with jacketed data, but the process of manufacture is most definitely plating.

I don't think the Speer FMJ bullets are plated. The Speer Reloading Manual gives the same load recipes for the .357 Sig FMJ and the .357 Sig Gold Dot. The Speer Gold Dot is definitely not plated. It the FMJ was plated, the copper would disintegrate at .357 Sig pressures. I'll try to cut one in half and see how thick the copper is. The FMJ resists crimping like jacketed bullets. By contrast, Ranier plated can be crimped very deeply and even indented. The copper on a plated bullet is typically only about as thick as a couple of sheets of paper.

 

[ljnowell]

I don't think the Speer FMJ bullets are plated. The Speer Reloading Manual gives the same load recipes for the .357 Sig FMJ and the .357 Sig Gold Dot. The Speer Gold Dot is definitely not plated. It the FMJ was plated, the copper would disintegrate at .357 Sig pressures. I'll try to cut one in half and see how thick the copper is. The FMJ resists crimping like jacketed bullets. By contrast, Ranier plated can be crimped very deeply and even indented. The copper on a plated bullet is typically only about as thick as a couple of sheets of paper.

I didnt say anything about FMJ. I said TMJ. You can cut as many of them in half as you want, Speer themselves will gladly tell you that they are a plated bullet. Thats the method of manufacturing. Yes, they are thick plating, but its still plating. Its not a drawn jacket type manufacturing. Also, speer gold dots are most definately plated also. When they say "Speer Gold Dot®. Using our proven Uni-Cor® technology, we bond the copper jacket to the lead core one molecule at a time. We've virtually wiped out the cause of most bullet failures — core-jacket separation" they are referring to plating. One molecule at a time. Not jacketed. Plated.

 

[ljnowell]

This is a good picture of gold dots going through their stages of manufacture:

 

[LockedBreech]

This is a good picture of gold dots going through their stages of manufacture:

Those are what I keep in my HD guns. Very neat!


Sent from my iPhone using Tapatalk

 

[Chief 0652]

The below is from the Speer website. For the product I mentioned, it says:"TMJ® - encased-core full jacket. Same loading data for the Gold Dot. You may be right. I don't think there are any regulations covering what manufacturers call their bullets.

Thanks for the pictures. I carry Cor-Bon personally. Don't know it they are jacketed, but they sure are fast.

#4731 - TMJ®
357 Sig - 357 SIG/38 Super TMJ FN (Value Pack)
Part Number Caliber
Grains/Grams Box Count Use
4731 357 Sig 125 / 8.1 600 3

Ballistic Coefficient Sectional Density Diameter Inches Diameter mm
0.147 0.142 0.355 9.017

4731

Usages:
1- Hunting, 2- Varmint, 3- Target / Plinker, 4- Personal Protection

Abbreviation Key:
BT - boat tail, CANN - cannelured, DC - DeepCurl™, FMJ - full metal jacket, FN - flat nose, GD - Gold Dot®, HP - hollow point, J - jacketed, L - lead, SB - Short Barrel®, SP - soft point, TMJ® - encased-core full jacket, RN - round nose, SWC - semi-wadcutter, WC - wadcutter, HBWC - hollow base wadcutter

 

[ljnowell]

The below is from the Speer website. For the product I mentioned, it says:"TMJ® - encased-core full jacket. Same loading data for the Gold Dot. You may be right. I don't think there are any regulations covering what manufacturers call their bullets.

Thats basically what it comes down to. There isnt anyone to set standards and thats fine, no government oversight is best! Speer refers to their plating as jackets. Which for all purposes they are. It serves the same purpose and is a thick plating. Its still plating though.

 

[hunterwinco]

I will carry what Chief 0652 said one step further...i think of plated bullets as cast bullets that have been essentially "spray painted" (even though it is "electro-plating")

 

[Canuck-IL]

The lack of standardized nomenclature is an ongoing issue that causes debate all the time ... IME, Rainier's have the thinnest and least even plating; Berry's double-struck are better in terms of even distribution of the plating and slightly thicker. The primo plated bullets that approach drawn-cup jacketed come from Speer, Extreme and Montana Gold.

Bottom line re accuracy is - you'll never see a plated bullet from any manufacturer on the 50 yard Bullseye line. For other purposes, most are fine - certainly cleaner than lead and, in normal times, reasonably priced.

 

[LiveLife]

Canuck-IL, good post illustrating plating vs jacketing thickness - http://www.thehighroad.org/showthread.php?p=8931306#post8931306

Speer TMJ: .015"
X-Treme: .010" - .012"
PowerBond/HSM: .010" - .011"
Berry's Thick Plated (TP): .012"
Berry's regular: .006" - .008" (thickness varies for caliber)
Rainier: .004"

I did a comparison thread showing what bullet bases and powders/charge weights were and TMJ bullet definitely looks like plated bullet - http://www.thehighroad.org/showthread.php?t=706260

Here's Blazer 9mm 124 gr TMJ

Speer/CCI isn't the only manufacturer using plated bullets in their factory ammo. Here's Remington 45ACP 230 gr factory round with plated bullet.

Bottom line re accuracy is - you'll never see a plated bullet from any manufacturer on the 50 yard Bullseye line. For other purposes, most are fine - certainly cleaner than lead and, in normal times, reasonably priced.

With plated bullets sized same as jacketed bullets, I wonder if excessive gas leakage around the bullet base is a factor that affects accuracy? I do know Berry's plated bullets come sized slightly larger than typical jacketed diameters (Berry's website advertises them to be larger sized) and notiiced some X-Treme plated bullets come sized larger depending on the caliber/bullet weight (Example: 9mm 147 gr RN come sized .356" and .357"). Perhaps the slightly larger bullet sizing helps produce more consistent chamber pressures for greater accuracy?