Please be Gentle Newb Question Rifle vs Handgun Ammo

[Greatwhitewing]

So fairly new to guns and shooting in general. Been focusing on 9mm handguns and have little bit better than beginner understanding of the format having a compact and full sized handgun and fired maybe a thousand rounds of various types.
Just staring to look at AR15/rifle options and 5.56mm/.223. Quite frankly taken aback by the "seemingly" low load numbers ie in 50-60'ish grain loads in rifle ammo vs the 115-174 grain loads in 9mm yet the rifle loads have higher velocity and better "bad guy" stopping power at longer distances. Obviously barrel length plays a big roll but is that the only reason.

So far web searching has shown me little but will keep looking. In the mean time any handy web references or simple "ex"splanations?

Thanks in advance

 

[240Geezer]

Physics
Smaller bullet at much higher velocity equals power.
Manufacturers list the power in ft/lbs( or metric equiv.) a quick Wiki of a cartridge will show you that.

 

[240Geezer]

5.56×45mm NATO - Wikipedia

en.m.wikipedia.org

 

[AtoTheK]

E=MC^2

The energy of any given thing is equal to its mass multiplied by its velocity squared.

There are tons of ballistic charts out there that you can compare different projectiles and their varying ft/lbs of energy. There are a million variables. Have fun! It’s interesting to me to look at different charts after many years of shooting and daydreaming and researching guns.

 

[Greatwhitewing]

5.56×45mm NATO - Wikipedia

en.m.wikipedia.org

Will review and thanks but I have some trust issues with wiked-pedia

 

[richc]

Back to physics:
E=MV^2

Energy = the mass of the projectile multiplied by the velocity squared.

It's all about the energy that is delivered by the projectile. Certainly projectile design comes into play in the wound cavity it produces. But it's really simple physics.

 

[Tinkermatic]

Watch this video, 2200 fps is what seems to separate rifles from handguns and temporary versus permanent wound cavities. Speed kills and lighter bullets are easier to get moving along with some alacrity.


View: https://youtu.be/T6kUvi72s0Y

Larger calibers (battle rifles!) such as .308, 30-06, 7.62x54r, and on up, combine speed and mass and now you have some serious stopping power. 150 grains moving close to 2,800-3,000 fps will do some damage as well ad increase effective range and recoil.

 

[SJan]

50-60'ish grain loads in rifle ammo vs the 115-174 grain loads in 9mm

that is referring to the weight of the bullet, in grains.
the ammo box may also show the bullet velocity out of a test barrel (may not exactly match your gun)
poke around wikipedia to get an idea of what some popular cartridges are capable of in regards to bullet weight / velocity

 

[walter62]

a small projo traveling at greater speed delivers more *energy* on target.

Energy is a squared function of velocity so changes in velocity yield big changes in energy.

My 68gn 9mm loaded w/ Silhouette has something like 550ft-lbs of energy whereas a
heavier/slower 9 is way down in the low 300's

which is why heavy hollow points dont make a lot of sense. (not fast enough to expand and penetrate
as well as lighter)

 

[paul73]

So fairly new to guns and shooting in general. Been focusing on 9mm handguns and have little bit better than beginner understanding of the format having a compact and full sized handgun and fired maybe a thousand rounds of various types.
Just staring to look at AR15/rifle options and 5.56mm/.223. Quite frankly taken aback by the "seemingly" low load numbers ie in 50-60'ish grain loads in rifle ammo vs the 115-174 grain loads in 9mm yet the rifle loads have higher velocity and better "bad guy" stopping power at longer distances. Obviously barrel length plays a big roll but is that the only reason.

So far web searching has shown me little but will keep looking. In the mean time any handy web references or simple "ex"splanations?

Thanks in advance

You are mixing up diff things.
The best stopping power is a 12ga shotgun slug.

 

[hpm]

Kinetic energy is mass of the object (bullet) multiplied by the square value of the speed and the result divided by two.
So speed plays a much greater role when it comes to the delivered kinetic energy (impact of bullet at target).

 

[240Geezer]

Will review and thanks but I have some trust issues with wiked-pedia

Just a quick example go for the deep dive.

 

[240Geezer]

You are mixing up diff things.
The best stopping power is a 12ga shotgun slug.

Gotta be SxS Joe says so.

 

[walter62]

If you have bullet in grains and velocity in FPS, then

energy = mass * (velocity^2)/450437

 

[thesyguy]

You are mixing up diff things.
The best stopping power is a 12ga shotgun slug.

If you like blowing limbs completely off, this is definitely the best method. Throw in a rifled barrel and it can do the same at a significant distance. Split a 13" vented brake rotor in half from 50-yards with my Mossberg.

 

[Greatwhitewing]

E=MC^2

The energy of any given thing is equal to its mass multiplied by its velocity squared.

There are tons of ballistic charts out there that you can compare different projectiles and their varying ft/lbs of energy. There are a million variables. Have fun! It’s interesting to me to look at different charts after many years of shooting and daydreaming and researching guns.

I sure get the energy thing and fully understand it. Before I shoot my mouth off I will look deeper butttttt (can't help myself) energy in a very small area has the proportional stopping power of a larger slower round?

 

[whacko]

You are mixing up diff things.
The best stopping power is a 12ga shotgun slug.

Absolutely the truth......at close range.

 

[kalash]

Fun fact: energy doesn't mean a thing in handguns.

 

[M1911]

Rifle cartridges run at much higher pressures on a much lighter bullet. So the bullet is going much, much faster.

 

[NHCraigT]

Fun fact: energy doesn't mean a thing in handguns.

View: https://www.youtube.com/watch?v=9hnaO8Dzb2Q

 

[whacko]

Fun fact: energy doesn't mean a thing in handguns.

Can you expand on this?

 

[Greatwhitewing]

Watch this video, 2200 fps is what seems to separate rifles from handguns and temporary versus permanent wound cavities. Speed kills and lighter bullets are easier to get moving along with some alacrity.


View: https://youtu.be/T6kUvi72s0Y

Larger calibers (battle rifles!) such as .308, 30-06, 7.62x54r, and on up, combine speed and mass and now you have some serious stopping power. 150 grains moving close to 2,800-3,000 fps will do some damage as well ad increase effective range and recoil.

Good video. Thanks

 

[Greatwhitewing]

You are mixing up diff things.
The best stopping power is a 12ga shotgun slug.

Don't doubt you buy why? Just as an mental exercise. Of course range is rather limited but probably fine foe home defense

 

[walter62]

Because people don't do well when they have large thru-holes in their bodies.

Rapid depressurization of their body.

WRT home defense; it wouldn't be my first choice. Maybe mix them up in the shotgun tube
along w/ some tasteful buckshot.

 

[walter62]

so, average 12g slug is 1oz (437grain) and often do around 1400FPS.

So that is about 1900+ ft-lbs of energy.

 

[fencer]

I sure get the energy thing and fully understand it. Before I shoot my mouth off I will look deeper butttttt (can't help myself) energy in a very small area has the proportional stopping power of a larger slower round?

It all comes down to "temporary wound cavity". Slow bullet, the tissue snaps right back and the channel created by the projectile is basically the same size as the projectile. At rifle velocities the wound cavity tears and rips tissue and does not close up. The magic number is about 2200 feet per second.

 

[whacko]

Don't doubt you buy why? Just as an mental exercise. Of course range is rather limited but probably fine foe home defense

Because it's a 1 ounce flat tipped slug of lead doing about 1600 fps. Under 75 yards that's devastating. 12 gauge slugs on deer anywhere near the "boiler room" and the deer hits the ground like it's anchored.

 

[kalash]

Can you expand on this?

Handgun rounds (carry calibers, not bear revolvers) don't go fast enough to reach energy levels that actually affect their performance. A rifle round packs so much energy that it tears a lot of tissue around the primary wound channel - handgun rounds can't do that, they just punch holes. This is only really important when debating defensive calibers - between 9mm, .40, .45, etc it makes no difference which one has more energy.

 

[appraiser]

Pistol barrels are not strong enough to contain the energy of a lot of powder so instead of generating energy with powder, they do it with bullet mass.

The other thing is the barrel lengths don't allow for a lot of powder.. the bullet is long gone before you can burn all the powder and get the pressures up, but again you are limited by the barrel strength.... or why you do not shoot hot ammo (+p etc) out of old guns that were not made for it.

 

[kalash]

Don't doubt you buy why? Just as an mental exercise. Of course range is rather limited but probably fine foe home defense

Multiple holes with every shot, enough power to break bones.