Grain Rating Debate
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Grain are just the weight of the bullet. The ability of the hollow point to open up depends on projectile weight and speed (increasing either makes it open faster). Adding weight also tends to increase penetration, so that can be helpful is a fast opening hollow point (because the large frontal area can't penetrate as far), but if the bullet already penetrates enough there's no point adding weight. Adding weight makes a projectile go slower (assuming a max load), so there is no blanket answer to the question.
It really comes down to what gun are you shooting it in (slow short barrel or fast long one), what was the round designed for (how much expansion and penetration), and does it actually work as designed in practical circumstances (e.g. penetrating clothes first before flesh, or a barrier).
You'll need to look for various gelatin tests for the rounds you're interested in.
It really comes down to what gun are you shooting it in (slow short barrel or fast long one), what was the round designed for (how much expansion and penetration), and does it actually work as designed in practical circumstances (e.g. penetrating clothes first before flesh, or a barrier).
You'll need to look for various gelatin tests for the rounds you're interested in.
Shawn Dodson
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Adequate penetration (minimum 12" penetration) is more important than the weight of the bullet.
Choose a cartridge whose bullet reliably penetrates a minimum of 12 inches when fired from your gun.
Some suggestions can be found here: http://www.m4carbine.net/showthread.php?t=19887
Choose a cartridge whose bullet reliably penetrates a minimum of 12 inches when fired from your gun.
Some suggestions can be found here: http://www.m4carbine.net/showthread.php?t=19887
Shawn Dodson
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Double tap
481
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Since penetration is the product of sectional density and velocity, heavy-for-caliber JHPs are the best choice because they have the highest sectional density- that is, 147s for 9mm, 180s for the .40/10mm, 230s for the .45ACP.
Sectional density diminishes with increasing expansion and heavier bullets suffer less (during expansion) than lighter bullets (of lower sectional density) given an equal amount expansion between the two- that is, heavy-for-caliber bullets offer the best possible penetration for any given expanded diameter.
Sectional density diminishes with increasing expansion and heavier bullets suffer less (during expansion) than lighter bullets (of lower sectional density) given an equal amount expansion between the two- that is, heavy-for-caliber bullets offer the best possible penetration for any given expanded diameter.
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otasan56
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I like a lighter 9mm bullet
like a 115gr +p+ JHP bullet.
like a 115gr +p+ JHP bullet.
As someone else said, adequate penetration is the first priority in bullet selection, reliable expanded diameter (or, in the case of lighter cartridges that you want FMJ to meet the penetration requirements, just the diameter). Shot placement is key as well, but doesn't really apply to ammo selection unless the ammo is downright terrible.
I prefer heavy-for-caliber. They tend to do what they do more consistently. The lighter and faster rounds tend to react more to barriers or heavy clothing that something heavy and slow will just truck through. Plus if something is going too fast, it will expand more violently, result in significantly reduced penetration. I prefer heavy.
I prefer heavy-for-caliber. They tend to do what they do more consistently. The lighter and faster rounds tend to react more to barriers or heavy clothing that something heavy and slow will just truck through. Plus if something is going too fast, it will expand more violently, result in significantly reduced penetration. I prefer heavy.
BaltimoreBoy
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I prefer 'medium' bullet weight JHP.
What's medium?
.357 Light-110 LowMed-125 HighMed-140 Heavy-158
45ACP Light-155 LowMed-185 HighMed-200 Heavy-230
44SPL Light-180 Med-200 Heavy-240
Many popular rounds are quite old. For some reason the folks from 100 years back always seemed to prefer heavy weights.
You can look at bullet effectiveness either from the viewpoint of momentum (P=mV) or energy (E=1/2mV**2)
Folks who prefer momentum tend to gravitate toward the heavies. Folks who like the highest energy like the mediums.
Note that with a given cartridge that usually if one lowers the mass one tends to increase the velocity. So looking at the equations one doesn't lose much in momentum when going lighter, but one does gain energy. However there is a diminishing return factor. When the projectile becomes too light you get a sort of whiffle ball effect. In other words you start losing both mass and velocity - not good.
If you look at some muzzle energies for a given caliber, the effective energies tend to peak in the middle of the mass range.
I think that is why the Marshall & Sanow studies came up with such a strong performance for the 125 gr .357.
What's medium?
.357 Light-110 LowMed-125 HighMed-140 Heavy-158
45ACP Light-155 LowMed-185 HighMed-200 Heavy-230
44SPL Light-180 Med-200 Heavy-240
Many popular rounds are quite old. For some reason the folks from 100 years back always seemed to prefer heavy weights.
You can look at bullet effectiveness either from the viewpoint of momentum (P=mV) or energy (E=1/2mV**2)
Folks who prefer momentum tend to gravitate toward the heavies. Folks who like the highest energy like the mediums.
Note that with a given cartridge that usually if one lowers the mass one tends to increase the velocity. So looking at the equations one doesn't lose much in momentum when going lighter, but one does gain energy. However there is a diminishing return factor. When the projectile becomes too light you get a sort of whiffle ball effect. In other words you start losing both mass and velocity - not good.
If you look at some muzzle energies for a given caliber, the effective energies tend to peak in the middle of the mass range.
I think that is why the Marshall & Sanow studies came up with such a strong performance for the 125 gr .357.
In all of the standard cartridges I've seen, I've never heard of this wiffle ball effect where you lose both mass and velocity. Unless you're talking about anemic loads.
Energy is a great stat to look at for what it's worth...but the actual energy of a handgun round has very little to do with the trauma it will deal to a soft target. Bullet construction plays a much bigger role. The goal isn't to transfer the most energy into the target, it is to create a hole deep and wide enough to stop the target fast. Higher energy can help...it can also hurt. Compare many 9mm 124-grain rounds with the same 9mm 124-grain +P round, and the +P will expand more, penetrate less. Which could mean more or less effectiveness, depending on how deep it would have penetrated to begin with.
Energy is a great stat to look at for what it's worth...but the actual energy of a handgun round has very little to do with the trauma it will deal to a soft target. Bullet construction plays a much bigger role. The goal isn't to transfer the most energy into the target, it is to create a hole deep and wide enough to stop the target fast. Higher energy can help...it can also hurt. Compare many 9mm 124-grain rounds with the same 9mm 124-grain +P round, and the +P will expand more, penetrate less. Which could mean more or less effectiveness, depending on how deep it would have penetrated to begin with.
firesky101
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I prefer heavy for caliber rounds in short barrels, as they suffer less of a velocity loss compared to their zippy lightweight brethren. For a duty size handgun I am comfortable with any standard weight, but gravitate towards the mid weights.
BaltimoreBoy
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Sorry Skribs, that was a bad analogy for me to use under the circumstances. No, I am not trying to redo Newtonian Physics.
What I was trying to get to is illustrated by what happens to muzzle energy as one varies bullet mass (but not type) over a range and uses the hottest load one reasonably can.
Let's take .357 as an example.
Typically the 158 gr load will have a respectable energy.
But if you drop to 125-140 you see an increase.
Drop down to 110 and you lose muzzle energy again - usually to even below the 158gr level.
For whatever reason (perhaps the limit on pressure for a given cartridge) there comes a point where you reduce the mass and you don't increase energy. Either you are not getting extra velocity or the extra one gets is not enough to compensate for the mass loss.
What I was trying to get to is illustrated by what happens to muzzle energy as one varies bullet mass (but not type) over a range and uses the hottest load one reasonably can.
Let's take .357 as an example.
Typically the 158 gr load will have a respectable energy.
But if you drop to 125-140 you see an increase.
Drop down to 110 and you lose muzzle energy again - usually to even below the 158gr level.
For whatever reason (perhaps the limit on pressure for a given cartridge) there comes a point where you reduce the mass and you don't increase energy. Either you are not getting extra velocity or the extra one gets is not enough to compensate for the mass loss.
JTQ
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I don't think I'd call your heavier numbers listed as "heavy". I'd call them "standard". Those are the weights those rounds originally came with. You can find factory ammo in heavier weights for all three.
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