TMJ vs FMJ

It makes absolutely no difference whatsoever whether the bullet is completely jacketed or everything but the base is jacketed. What Berry's Bullets are you afraid of exceeding the maximum velocity? I suspect it is more the way they're manufactured than any performance issue. The only place you may run into an issue is with .44 (.429") bullets designed for a pistol and you shoot them out of a .444 Marlin. That could maybe lead to some sort of failure, but you're never going to get there with even a 12" barreled pistol. You would blow the gun up before you could hit those kind of velocities...


A common problem in handguns is the terminal balistics of bullets not achieving sufficient velocity fully open hollow points. With the possible exception of riflelike handguns no pistol cartridge is going to reach a velocity close to coming apart even if it's an unjacketed cast bullet.

IMHO
 
The reason some plated bullets have a velocity limit is because the plating is very thin. Berry thick plated bullets have a higher velocity rating. Speer TMJ bullets are thicker still. This is important because there are a myriad of firearms out there with different types of rifling and some will cripple a plated bullet under certain circumstances. Berry doesn’t know if you’re going to shoot them out of an older deep rifled gun at high velocity or a polygonal barrel at low velocity. So they make both.
 
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It makes absolutely no difference whatsoever whether the bullet is completely jacketed or everything but the base is jacketed. What Berry's Bullets are you afraid of exceeding the maximum velocity? I suspect it is more the way they're manufactured than any performance issue. The only place you may run into an issue is with .44 (.429") bullets designed for a pistol and you shoot them out of a .444 Marlin. That could maybe lead to some sort of failure, but you're never going to get there with even a 12" barreled pistol. You would blow the gun up before you could hit those kind of velocities...


A common problem in handguns is the terminal balistics of bullets not achieving sufficient velocity fully open hollow points. With the possible exception of riflelike handguns no pistol cartridge is going to reach a velocity close to coming apart even if it's an unjacketed cast bullet.

IMHO
Thanks for your input… very thorough 👍
 
The reason some plated bullets have a velocity limit is because the plating is very thin. Berry thick plated bullets have a higher velocity rating. Speer TMJ bullets are thicker still. This is important because there are a myriad of firearms out there with different types of rifling and some will cripple a plated bullet under certain circumstances. Berry doesn’t know if you’re going to shoot them out of an older deep rifled gun at high velocity or a polygonal barrel at low velocity. So they make both.
Great info… thank you.
 
The reason some plated bullets have a velocity limit is because the plating is very thin. Berry thick plated bullets have a higher velocity rating. Speer TMJ bullets are thicker still. This is important because there are a myriad of firearms out there with different types of rifling and some will cripple a plated bullet under certain circumstances. Berry doesn’t know if you’re going to shoot them out of an older deep rifled gun at high velocity or a polygonal barrel at low velocity. So they make both.
That said i shoot a ton of plated bullet out of my 16” 9mm AR and I can’t say I’ve ever had an issue.
I’m guessing it’s just a regular button barrel.
 
It makes absolutely no difference whatsoever whether the bullet is completely jacketed or everything but the base is jacketed. What Berry's Bullets are you afraid of exceeding the maximum velocity? I suspect it is more the way they're manufactured than any performance issue. The only place you may run into an issue is with .44 (.429") bullets designed for a pistol and you shoot them out of a .444 Marlin. That could maybe lead to some sort of failure, but you're never going to get there with even a 12" barreled pistol. You would blow the gun up before you could hit those kind of velocities...


A common problem in handguns is the terminal balistics of bullets not achieving sufficient velocity fully open hollow points. With the possible exception of riflelike handguns no pistol cartridge is going to reach a velocity close to coming apart even if it's an unjacketed cast bullet.

IMHO

There is a fairly substantial difference between FMJ and TMJ with regard to pistols and how they are loaded. Pistol powder burns hot enough to vaporize exposed lead resulting in leaded comps and ports. The primary reason you see JHP used with major power factor in USPSA is because JHP do not have exposed lead bases. Same goes for TMJ. This isn't too much of an issue with lighter loads but as the pressures rise so does the heat the exposed lead base will experience.

Coated and plated lead bullets typically have a stated maximum velocity because if you push them too hard you'll cut the jackets and lead the barrel or comps/ports. As mentioned by someone else, thicker plating is used to mitigate the problem.
 
That said i shoot a ton of plated bullet out of my 16” 9mm AR and I can’t say I’ve ever had an issue.
I’m guessing it’s just a regular button barrel.

It is really only an issue if you're trying to make major power factor out of a pistol. To get a 124gr to 1350fps and higher out of a 4" or shorter barrel requires a lot of chamber pressure. Assuming you'd even want to do that with a 16" AR you wouldn't need nearly as hot a load.