- My Forums
- Tiger Rant
- LSU Recruiting
- SEC Rant
- Saints Talk
- Pelicans Talk
- More Sports Board
- Fantasy Sports
- Golf Board
- Soccer Board
- O-T Lounge
- Tech Board
- Home/Garden Board
- Outdoor Board
- Health/Fitness Board
- Movie/TV Board
- Book Board
- Music Board
- Political Talk
- Money Talk
- Fark Board
- Gaming Board
- Travel Board
- Food/Drink Board
- Ticket Exchange
- TD Help Board
Customize My Forums- View All Forums
- Show Left Links
- Topic Sort Options
- Trending Topics
- Recent Topics
- Active Topics
Started By
Message
re: Help dispell a rumor: Ammo has greater penetration at further distances
Posted on 5/17/12 at 1:58 pm to C
Posted on 5/17/12 at 1:58 pm to C
I would think in regards to close range that bullets seem more likely to pass through the target with smaller expansion than at greater ranges with the slower bullet speed. Seems like I saw a show once about some WWII soldier preferring the carbine to the Garrand because the bullet was slower and had greater stopping power.
As for shooting a bullet from a height downward, the bullet will still slow down as it still has to pass through air. Gravity will just have its affect on it but a bullet will eventually slow to the same rate of fall as a rock.
As for shooting a bullet from a height downward, the bullet will still slow down as it still has to pass through air. Gravity will just have its affect on it but a bullet will eventually slow to the same rate of fall as a rock.
This post was edited on 5/17/12 at 2:06 pm
1
Posted on 5/17/12 at 2:01 pm to TigerDeacon
It just depends on the bullet construction. A frangible will definitely penetrate more at lower velocity.
For most common types of ammo higher velocity=deeper penetration. The only way that isnt true is if the bullet cant stay together at high velocity.
For most common types of ammo higher velocity=deeper penetration. The only way that isnt true is if the bullet cant stay together at high velocity.
Posted on 5/17/12 at 2:27 pm to Bleeding purple
quote:
Assume mythbusters did a show on this:
Do you think they have a chance?
We should invite them to come to the OBGT and do the show while we watched drinking cheap beer.
Posted on 5/17/12 at 3:27 pm to Bleeding purple
quote:
There are many variables involved in the fragementation and deformation of a projectile. Unless there is a reduced force at which a particular projectile has a lower fragmentation or deformation rate than it does when at the higher force of full muzzle velocity, penetration at close ranges would be higher.
unless I am missing something.
You pretty much nailed it, but I'll point out even in fragmentation momentum is conserved. Every fragment's energy and momentum simply sum up to what the bullet had just as it hit. Both are directly related to velocity, which is constantly decreasing.
In fragmentation, the mass doesn't matter, but friction due to surface area does. It's possible, if the bullet is brittle enough, for it to penetrate less at a closer range.
Think about dropping an egg into water. If you throw it, it will break and splatter on the surface. If you drop it lightly, it will hit the water and sink a little, staying whole.
Posted on 5/17/12 at 3:46 pm to TheDrunkenTigah
quote:
You pretty much nailed it,
quote:
In fragmentation, the mass doesn't matter, but friction due to surface area does
quote:
Every fragment's energy and momentum simply sum up to what the bullet had just prior to fragmenting
This does not mean that each fragment has the same energy or momentum as the inital projectile. It means each fragment has a frction of the energy. It will conceivably have nearly the same velocity with loses only to the friction of the impact but the mass of each fragment is much less. Thus, each fragment will have much less momentem. Surface area also effects the drag on each fragment and that too increases with fragmentation and deformation. However, I assure you the loss of mass per fragment does indeed effect the penetration of each individual fragment.
Posted on 5/17/12 at 3:49 pm to Bleeding purple
Correct.
If a bullet splits in two, those parts will penetrate more than the pieces of a bullet that broke up into 100 pieces.
If a bullet splits in two, those parts will penetrate more than the pieces of a bullet that broke up into 100 pieces.
Posted on 5/17/12 at 3:54 pm to Bleeding purple
quote:
It means each fragment has a fraction of the energy.
quote:
Thus, each fragment will have much less momentem.
Right, my only point was that if you summed all the fractions, they would equal the initial. The only mechanism by which any energy or momentum is "lost" is through friction (dissipated as heat), which is related to total surface area. More fragments, more surface area, more friction. The mass is constant throughout, but the more pieces it's divided by is the loss of penetration.
Posted on 5/17/12 at 4:15 pm to TheDrunkenTigah
correct. 
Posted on 5/17/12 at 4:44 pm to Bleeding purple
False, in theory but true in practice.
Shoot a deer at 30 yards with a 150 grain Hornady Ballistic Tip with a 300 Win Mag at something like 3200 or 3300 fps, and you will get a blowup on the shoulder with no real penetration and an ugly, but largely superficial wound.
Should the same deer with the same load at 200 yards where the velocity has slowed to a more reasonaly number below 3000 fps and you get better bullet performance and penetration.
Shoot a deer at 30 yards with a 150 grain Hornady Ballistic Tip with a 300 Win Mag at something like 3200 or 3300 fps, and you will get a blowup on the shoulder with no real penetration and an ugly, but largely superficial wound.
Should the same deer with the same load at 200 yards where the velocity has slowed to a more reasonaly number below 3000 fps and you get better bullet performance and penetration.
Posted on 5/17/12 at 6:04 pm to C
If yall want to donate, lets order some ballistics gel. I have a range where we can do pretty much whatever we want. We can get the GoPros out and do this all ourselves.
Posted on 5/17/12 at 8:32 pm to kengel2
Downshift, you were on the right track.
Hawgon, you're right on.
I can tell you without a fact that an expanding hunting bullet (specifically a 30 caliber Nosler Ballistic Tip) penetrates deeper at lower velocity than it does at higher velocity. It seems counterintuitive, but it's true. It's really not that complicated when one thinks about it. It really comes down to the purpose of a hunting bullet-to expand so that it creates a bigger wound channel As velocity increases, the bullet expands more, resulting in less penetration. At lower velocities, the bullet expands less, thereby penetrating deeper .
My son and I did this as a science project for 3 or 4 years. I had read of this in a hunting magazine article and thought it would make a good project. We shot a number of different weight Nosler Ballistic Tip bullets through his 308 Win, across a chronograph and into a water soaked stack of newspaper. The first year we shot the 125 gr Nosler BT at different velocities (IIRC about 2300-2700 fps). As the study evolved, we later shot 150, 165 and 180 gr NBT bullets. One year we even added a 150 gr full metal jacket bullet. I expected the FMJ to penetrate very well, but it didn't penetrate as deep as others as the bullet separated at the cannalure.
Our basic findings: Using a hunting bullet designed to expand, bullet penetration decreases as velocity increases.
Comparing bullets of like construction and muzzle velocity, bullet penetration increases as bullet weight increases.
At muzzle velocity less than 2600 fps, the 125 NBT is a good hunting bullet as it holds together well, expands nicely and penetrates deeply. He ended up killing 12 deer w/ that bullet.
The only bullet that fragmented on us (other than the FMJ) was the 125 NBT at greater than 2600 fps muzzle velocity.
ETA: This correlates w/ an expanding hunting bullet penetrates deeper as the distance increases. I'm sure there's a point at which velocity drops so low and distance increases so much that penetration drops off, but I don't know the answer to that. The year we were going to study that we didn't have to do a science fair project.
quote:
It is possible since the lower velocity might not be capable of opening the bullet up if we're talking about expanding bullets.
Hawgon, you're right on.
quote:
False, in theory but true in practice.
Shoot a deer at 30 yards with a 150 grain Hornady Ballistic Tip with a 300 Win Mag at something like 3200 or 3300 fps, and you will get a blowup on the shoulder with no real penetration and an ugly, but largely superficial wound.
Should the same deer with the same load at 200 yards where the velocity has slowed to a more reasonaly number below 3000 fps and you get better bullet performance and penetration.
I can tell you without a fact that an expanding hunting bullet (specifically a 30 caliber Nosler Ballistic Tip) penetrates deeper at lower velocity than it does at higher velocity. It seems counterintuitive, but it's true. It's really not that complicated when one thinks about it. It really comes down to the purpose of a hunting bullet-to expand so that it creates a bigger wound channel As velocity increases, the bullet expands more, resulting in less penetration. At lower velocities, the bullet expands less, thereby penetrating deeper .
My son and I did this as a science project for 3 or 4 years. I had read of this in a hunting magazine article and thought it would make a good project. We shot a number of different weight Nosler Ballistic Tip bullets through his 308 Win, across a chronograph and into a water soaked stack of newspaper. The first year we shot the 125 gr Nosler BT at different velocities (IIRC about 2300-2700 fps). As the study evolved, we later shot 150, 165 and 180 gr NBT bullets. One year we even added a 150 gr full metal jacket bullet. I expected the FMJ to penetrate very well, but it didn't penetrate as deep as others as the bullet separated at the cannalure.
Our basic findings: Using a hunting bullet designed to expand, bullet penetration decreases as velocity increases.
Comparing bullets of like construction and muzzle velocity, bullet penetration increases as bullet weight increases.
At muzzle velocity less than 2600 fps, the 125 NBT is a good hunting bullet as it holds together well, expands nicely and penetrates deeply. He ended up killing 12 deer w/ that bullet.
The only bullet that fragmented on us (other than the FMJ) was the 125 NBT at greater than 2600 fps muzzle velocity.
ETA: This correlates w/ an expanding hunting bullet penetrates deeper as the distance increases. I'm sure there's a point at which velocity drops so low and distance increases so much that penetration drops off, but I don't know the answer to that. The year we were going to study that we didn't have to do a science fair project.
This post was edited on 5/17/12 at 9:07 pm
Posted on 5/17/12 at 8:37 pm to Nodust
quote:
Until it reaches 399 yards
Posted on 5/18/12 at 9:33 am to TigerOnThe Hill
quote:
TigerOnThe Hill
Any chance you documented your results? I'd love to see it.
Posted on 5/18/12 at 12:06 pm to C
C,
Oh yeah, I've got all kinds of results and documentation (pics, spread sheets, written report, etc). We did variations on the project for 3 or 4 years. Heck, we've probably still got the presentation boards in storage! It really makes for a nice project that doesn't take an unreasonalbe amount of time to do and put together. Plus, most kids that hunt will like another opportunity to go shooting.
quote:
Any chance you documented your results? I'd love to see it.
Oh yeah, I've got all kinds of results and documentation (pics, spread sheets, written report, etc). We did variations on the project for 3 or 4 years. Heck, we've probably still got the presentation boards in storage! It really makes for a nice project that doesn't take an unreasonalbe amount of time to do and put together. Plus, most kids that hunt will like another opportunity to go shooting.
Posted on 5/18/12 at 1:27 pm to Hawgon
quote:
Shoot a deer at 30 yards with a 150 grain Hornady Ballistic Tip
It's the bullet that is the problem here. You could shoot the same load with a Barnes X, Fusion or Nosler Accubond and they will pretty much perform the same at all ranges. Great penetration and an excellent wound canal.
Posted on 5/20/12 at 3:29 pm to Zukitiger
quote:
Shoot a deer at 30 yards with a 150 grain Hornady Ballistic Tip
It's the bullet that is the problem here.
It's a given that the Ballistic Tip bullets are constructed to perform well on thin skinned big game. All bullets are designed to operate within an impact velocity. I don't think the Ballistic Tip is very forgiving at the uppper end of its' operating velocity. In other words, when pushed to impact at velocities above it's operating range, the BT can become too fragile and not penetrate very well. OTOH, at lower velocities, the BT is a VERY effective hunting round. The BT is the bullet of choice for hunting thin skinned big game w/ most of the types of handguns I hunt w/.
Posted on 5/21/12 at 4:00 pm to Zukitiger
quote:
It's the bullet that is the problem here. You could shoot the same load with a Barnes X, Fusion or Nosler Accubond and they will pretty much perform the same at all ranges. Great penetration and an excellent wound canal.
That is why I said it is false in theory and true in practice.
All else being equal, higher velocity equals higher penetration. It is simple physics. However, bullet construction is an introduced variable that changes things up somewhat.
It is most obvious with something like a ballistic tip, but even something like a Barnes X will sacrifice some penetration when expansion is overly violent due to extreme velocity. On something like deer, it wouldn't be enough to ever notice. On something like an elephant skull or a cape buffalo shoulder? It might be important.
Page 3 of 3
Popular
Back to top
Follow TigerDroppings for LSU Football News