Different Diameters?
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Blue68f100
Member
Jacketed normally run at 0.451"
Lead bullets can run 0.001"-0.002" larger.
Plated fall some where in between depending on mfg.
We like choices....
Not all 45 cal bullets are for the 45acp, too
Lead bullets can run 0.001"-0.002" larger.
Plated fall some where in between depending on mfg.
We like choices....
Not all 45 cal bullets are for the 45acp, too
Sam1911
Moderator Emeritus
First and simplest answer is that jacketed bullets and cast lead bullets are always sized slightly differently because of how the harder surface metal of a jacketed bullet grabs the rifling.
So you'll see that a jacketed bullet for a .45 ACP will measure 0.451" or so and a cast bullet for the same round will usually measure 0.452. The softer bare lead engraves more easily in the rifling and so can (and needs to) be a little larger in diameter to start with.
The difference is well pronounced for .44 Mag/Spc. bullets, where jacketed are always sold at 0.429" and cast are usually 0.431".
The next level answer is that guns actually measure all over the place for real groove diameter. Some are more consistent than others, but when you're trying to chase down a problem with a gun that tends to "lead up" a lot with cast bullets, you'll often find that the real groove diameter is several ten thousandths larger than you'd expect. And good manufacturers cover that problem by offering bullets of some larger diameters so you can get a good fit and bore seal.
Then, there's the fact that there are several nominal calibers which actually have completely different specified bullet diameters. For example, .45 Colt and .45 ACP are not the same diameter, traditionally anyway. Many .45 Colt guns want a 0.454" bullet, or greater. (And if you jump to .45-70s, that's getting up toward 0.459"!) Similar things happen between traditional .44-40 and modern .44 Mag. revolvers.
So you'll see that a jacketed bullet for a .45 ACP will measure 0.451" or so and a cast bullet for the same round will usually measure 0.452. The softer bare lead engraves more easily in the rifling and so can (and needs to) be a little larger in diameter to start with.
The difference is well pronounced for .44 Mag/Spc. bullets, where jacketed are always sold at 0.429" and cast are usually 0.431".
The next level answer is that guns actually measure all over the place for real groove diameter. Some are more consistent than others, but when you're trying to chase down a problem with a gun that tends to "lead up" a lot with cast bullets, you'll often find that the real groove diameter is several ten thousandths larger than you'd expect. And good manufacturers cover that problem by offering bullets of some larger diameters so you can get a good fit and bore seal.
Then, there's the fact that there are several nominal calibers which actually have completely different specified bullet diameters. For example, .45 Colt and .45 ACP are not the same diameter, traditionally anyway. Many .45 Colt guns want a 0.454" bullet, or greater. (And if you jump to .45-70s, that's getting up toward 0.459"!) Similar things happen between traditional .44-40 and modern .44 Mag. revolvers.
ArchAngelCD
Member.
In short, because of gun manufacturing back 150 years.
.451" or .452" for the .45 ACP and current 45 Colts.
.450" to .454" for older 45 Colts.
Lead bullets are usually .001" wider than jacketed bullets.
The other 45s were mapped out well above.
.451" or .452" for the .45 ACP and current 45 Colts.
.450" to .454" for older 45 Colts.
Lead bullets are usually .001" wider than jacketed bullets.
The other 45s were mapped out well above.
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Blue68f100
Member
Reloaders have bumping down to a science, seems the response always starts with "I bump ...etc.", I have two 45 ACP pistols that do not like cases that have the appearance of having swallowed a bullet, it could be said the cases have a bullet line.
To 'fix' those cases I run them through a carbide sizing die, after running the case through the carbide die the loaded ammo matches factory loaded 45 ACP ammo. I can size bullets. Increasing the diameter is a little more difficult. To increase the diameter I have to pump the bullets up in diameter.
F. Guffey
To 'fix' those cases I run them through a carbide sizing die, after running the case through the carbide die the loaded ammo matches factory loaded 45 ACP ammo. I can size bullets. Increasing the diameter is a little more difficult. To increase the diameter I have to pump the bullets up in diameter.
F. Guffey
gwpercle
Member
One size just doesn't fit all ! Kind of like shoes.
I have one 45 that likes .453 and another that will not accept anything more than .451... .452 and they will not chamber, .451 and they chamber just fine , you have to size them to fit.
I have one 45 that likes .453 and another that will not accept anything more than .451... .452 and they will not chamber, .451 and they chamber just fine , you have to size them to fit.
ArchAngelCD
Member.
That would make it very hard to seat or even start
You have a missing "0"
Yeah, this darn Kindle sometimes decided it knows what I want to write better than me. I will fix it, thanks...
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