Ammo Hunt, FMJ v.s. TMJ

[Good Ol' Boy]

Ok I think I know the differences between the two, total is the entire bullet plated versus full the bullet is plated to the casing.

My question is there any reason not to by TMJ for general shooting use? IE comps, practice, training.

I see some of these ads for TMJ saying "NOT" target ammo but training ammo.

I just wanna make sure if I buy some TMJ I'm not going to be shunned at my next match or have issues shooting my steel at home.

 

[Buzznrose]

https://ammo.com/bullet-type/total-metal-jacket-tmj

“
Shooting Properties: FMJ vs. TMJ
Both types of ammunition are [URL='http://www.differencebetween.net/object/difference-between-tmj-and-fmj/']almost identical when it comes to accuracy and velocity. The TMJ round is suitable for target shooting, as is the FMJ. But when it comes to hunting, the TMJ is not always the best choice, as it won't expand as well as other bullets like the hollow point. However, for hunting large game that requires deep penetration, the TMJ (like the FMJ) could be the best choice.”[/URL]

I use Speer Lawman TMJ sometimes...shoots fine for me

 

[DairyVet]

https://ammo.com/bullet-type/total-metal-jacket-tmj

“
Shooting Properties: FMJ vs. TMJ
Both types of ammunition are almost identical when it comes to accuracy and velocity. The TMJ round is suitable for target shooting, as is the FMJ. But when it comes to hunting, the TMJ is not always the best choice, as it won't expand as well as other bullets like the hollow point. However, for hunting large game that requires deep penetration, the TMJ (like the FMJ) could be the best choice.”

I use Speer Lawman TMJ sometimes...shoots fine for me

I don’t think this accurately addresses the difference. Most FMJ bullets I’ve seen have exposed lead in the base of the bullet (nose and sides are jacketed. TMJ by comparison have the jacket completely surrounding the lead core - including the bullet base.

Edited to add: can’t see a reason NOT to use TMJ other than slightly higher cost.

 

[mcb]

Those terms like FMJ and TMJ are far from a clean cut and defined terms/abreviation. FMJ is a fairly well defined and accepted and yet we do see variation in construction bunched under the term FMJ. TMJ is even more nebulously defined. I have seen TMJ used for both jacketed and plated bullets so you need to do some research into the exact construction of a particular brand that uses the term. There is also CMJ (Complete Metal Jacket) use by Montana Gold and maybe a few others.

As for its use, have at it. If the price is right and they shoot good in your gun use them.

 

[CDW4ME]

At least with TMJ/FMJ it is not slang.
Know what is annoying? Referring to 45 acp FMJ as "hardball". Oh, you got some 45 "softball"?

 

[Jim Watson]

There is another thread on the subject but...
TMJ (Total Metal Jacket) is a Speer trademark for bullets so thickly plated all over as to amount to a jacket.
When not to use? Well, I have not heard of anybody shooting TMJ at 50 yard line slow fire. I conclude that drawn jackets are more accurate.

FMJ (Full Metal Jacket) is a non-trademarked term for bullets with mechanically drawn jackets over the lead core. These days, some have separate base closures to keep lead away from the powder flame. The Montana Gold CMJ (Complete Metal Jacket) is one. I have shot Hornady bullets made this way but they don't have a catchy name for it.

 

[MistWolf]

At least with TMJ/FMJ it is not slang.
Know what is annoying? Referring to 45 acp FMJ as "hardball". Oh, you got some 45 "softball"?

Yes. Yes, we do. There are reduced loads for the 45 ACP colloquially known as "softball" because they have softer recoil.

 

[labnoti]

Speer's TMJ have a thick layer of plating that allows higher velocity than thin plated bullets. They should be good for ~1500 fps, whereas Berry's and Rainier are rated for closer to ~1200 fps. RMR also produces plated bullets that are rated for higher velocities. I have not had leading issues from any of these when used at suitable velocities. I shoot heavier bullets from handguns so exceeding 1500 fps is not likely.

I do not test for accuracy. My revolver is very accurate and I would need a Ransom Rest and magnified optic etc. to eliminate things that aren't related to the bullet's accuracy. Basically, all these bullets can produce tight groups at 25 or 50 yards but comparing the groups fairly would involve a lot of work. I do measure velocities and this is where my experience with plated bullets comes apart.

Speer TMJ, RMR plated, and Berry's plated all produce wide extreme spreads, 50 or even 100 or more fps when tested with more than 10 different powders. There are only a few combinations where I can get SD < 20 fps and only for 5-shots. The more I shoot, the more it comes apart.

If I use the same exact reloading procedures but switch to jacketed hollowpoint XTP, my ES shrinks and SD is 25 fps or less for all the powders I test. For the most consistent loads (HP-38), I can get the SD down as low as 4 fps for 5-shots, and it stays low as I shoot more.

My conclusion is that plated bullets (TMJ) aren't as consistent from my gun as JHP. I still shoot plated bullets by far more than anything else because they're cheap and they're still accurate enough within 50 yards that they easily meet my needs for practice. They're also lead-safe. I won't shoot FMJ with exposed lead bases.

 

[Buzznrose]

I don’t think this accurately addresses the difference. Most FMJ bullets I’ve seen have exposed lead in the base of the bullet (nose and sides are jacketed. TMJ by comparison have the jacket completely surrounding the lead core - including the bullet base.

Edited to add: can’t see a reason NOT to use TMJ other than slightly higher cost.

You obviously didn’t go to the article at the link I posted.

I cut and pasted the part I thought addressed the OP’s question, but also the link to the article with more info.

 

[DairyVet]

You obviously didn’t go to the article at the link I posted.

I cut and pasted the part I thought addressed the OP’s question, but also the link to the article with more info.

That is correct. I apologize but I did not follow the link.
Didn’t see the relevance to the OP with the hunting/hollow point reference without mentioning difference between FMJ and TMJ.

That said, your quote was accurate with respect to suitability for target shooting.

OPs understanding of the difference in construction was close except for the extent of the jacket in an FMJ (all the way to the base) and the fact that plating and jacketing aren’t equivalent processes.

 

[CDW4ME]

Yes. Yes, we do. There are reduced loads for the 45 ACP colloquially known as "softball" because they have softer recoil.

I was a new shooter about 32 years ago, it was common in gun magazines for writers to refer to 45 "hardball".
If one went to buy 45 "hardball" good luck finding a box with that description.
I've never seen 9mm FMJ referred to as "hardball" - slang applied selectively.

 

[Jim Watson]

I make up my own slang. Cheap roundnose ammo is "econoball."

 

[MislMan]

At least with TMJ/FMJ it is not slang.
Know what is annoying? Referring to 45 acp FMJ as "hardball". Oh, you got some 45 "softball"?

Cast lead 45 cal ammo (45 ACP) would be ‘softball’. Just lead with no jacket allows for bullet expansion and less penetration while jacketed 45 ACP (hardball) does not expand and pretty much punches right through with heavy penetration.

 

[Good Ol' Boy]

OPs understanding of the difference in construction was close except for the extent of the jacket in an FMJ (all the way to the base) and the fact that plating and jacketing aren’t equivalent processes.

I've always used the terms jacket and plating interchangeable. So what is the difference?

FWIW after reading the responses here (all very appreciated) I went and dug a few bullets out of the sand in my backstop and found some had plating or jacket all the way around the entire bullet and some had only to the bottom of the side, the bottom of the bullet was exposed. I've never bought anything but FMJ labeled ammo for practice so that was interesting to find out.


I dont reload so I originally posted the question because some sites I've been seeing TMJ ammo for sale was cheaper than FMJ, and of course what the actual difference was between the two.


Much thanks for the responses.

 

[jmr40]

TMJ is designed to reduce the amount of lead dust in the air inside of indoor shooting ranges. Other than that it works just like FMJ

https://www.bing.com/search?q=tmj+b...7002e4d099218a3da22d16bcf&cc=US&setlang=en-US

 

[Outlaw75]

I've always used the terms jacket and plating interchangeable. So what is the difference?

Plating is causing a layer of metal to adhere to a conductive surface (in this case a lead bullet) using electrical or chemical means. Jacketing is done by drawing or swaging a metal skin over a lead bullet and is a physical process.

This will explain swaging vs. drawing in more detail: http://www.corbins.com/intro.htm
(Also give you some swaging presses to lust over. )

But they are two different processes giving different results.

 

[DairyVet]

Plating is causing a layer of metal to adhere to a conductive surface (in this case a lead bullet) using electrical or chemical means. Jacketing is done by drawing or swaging a metal skin over a lead bullet and is a physical process.

This will explain swaging vs. drawing in more detail: http://www.corbins.com/intro.htm
(Also give you some swaging presses to lust over. )

But they are two different processes giving different results.

I came here to post something explaining the jacketing process, but the corbins link was 10x better than what I'd found. Thanks for sharing!