Your thoughts on downrange energy...

[Zugunruhe]

I think it was Elmer Keith that came up with the rule of thumb that it takes 800 ft. lbs. of energy to cleanly dispatch medium sized game. What are your thoughts on this? I mean seriously, does a deer know the difference between 700 ft. lbs. and 800 ft. lbs. down range?

I ask this because I repeatedly see kills on here at ranges far greater than where the bullet "should" be performing according to the above logic. For instance, a common load of 85 or 90 grains of Pyro RS and a 240gr. XTP moves out of the barrel at a little over 1600 fps. According to the ballistics tables, this load dips below the 800 ft. lbs. of energy at around 136 yards but I know we've seen reports here of longer shots with that powder/bullet combination.

Is this just another "how dead is dead" exercise, or is the 800 ft. lbs. benchmark a useful thought for bullet selection?

I ask this partly because my gun dislikes 777, crud rings so bad that even the second shot after a wet patch/dry patch is difficult to load irrespective of bullet type (sabot or conical). I'd like the extra velocity boost that 777 offers to up downrange energy, but if it cruds up my rifle I'll stick with RS.

 

[cayuga]

Personally I do not get too excited on ballistic charts. Granted they are of value in helping to judge whether a projectile will work for the needed hunting situation, but they are not the only thing to consider. Shot placement is the big factor to me.

Also I think too much importance is placed on velocity of projectiles. I read a lot of posts about people pushing the projectile as hard and fast as they can. That is all fine and good, but make sure that the projectile you are going to do this with is designed for this kind of velocity.

For instance, I was talking to a person about the simple 240 grain XTP. He shoots them with 80 grains of powder. He says, with that simple charge, he gets excellent penetration, expansion, and has yet to loose a deer to them. BUT he is careful of his distances.

The simple roundball is a deadly projectile. Yet if you look at the ballistic tables, it makes no sense. Its shot placement, bullet expansion, and how the animal reacts to muzzleloader projecitles. I personally think they react different from a muzzleloader to a center fire. I have shot deer, that stood there, then just fell over. They never ran off. They never dropped. Yet with a 30-06 I have shot them in a dead drop place, and had them bolt off. Granted they did not go far, but still.. there is something about muzzleloaders I can not place my finger on.

 

[tooldog]

I try not to worry so much about ft/lbs. of energy and worry more about bullet performance and penetration at the impact speed. In your case, the .44 cal 240 gr. XTP bullet is designed for speeds between 900 and 1800 fps. (The .45 cal 240 gr XTP/MAG is designed for 1100 to 2100 fps.) Even at 150 yards the bullet is carrying 770 ft/lbs @ 1200 fps which is still perfectly acceptable for this bullets design parameters (assuming your example of 1600 fps @ the muzzle).

My 2 cents...

tooldog

 

[Zugunruhe]

Great point tooldog- I hadn't thought about the velocities at which the bullet was designed to perform. That is a critical element in the equation, right along with shot placement. If you put that bullet where it needs to be, theoretically it will do its job. Cool!

 

[vabowhntr]

I don't get too excited about KE, I am more of a believer in momentum and the ability of something to penetrate. If I put a bullet through both lungs and/or heart of a deer, it is going to die if it is done with 250 fpe or 2000 fpe. That is why I always have gone towards a heavy for caliber bullet. Like with my .45 cal White I shoot the 460 gr NE bullets. Even at just over 1000 fps, they seem t go through the deer every time. Sometimes I have to track em 120 yards, but with the bloodtrails from 2 holes, it is pretty easy.

Also, my favorite deer rifle is one in 30-30 with 170 gr bullets. Very accurate at the ranges I hunt and the bullets always seem to perform well.

 

[Zugunruhe]

Here is a great read I found on the subject, it answers a lot of questions about why muzzleloading bullets just seem to be so effective on game.

http://www.shootingtimes.com/ammunition/hunt_121305/index.html

 

[jaybe]

Good article, Zagunrue; it does explain a lot about the phenomenon of the slower moving, heavier bullet.
I would think, though, that a combination of both penetration AND expansion would be the best of both worlds. That's probably what most bullet manufacturers aim for, too.
Last year I shot a large doe with a 460 gr. flat-nosed conical ahead of 90 gr. T7. The slug entered just behind the right shoulder and passed diagonally through the deer, exiting the center of the opposite ham, leaving a hole very similar to the entrance hole. It was nice to not ruin the ham with lots of expansion, but it's pretty obvious that if the shot had been broadside it would have certainly gone through without any expansion at all. I've been wondering how much faster the bullet would have to travel to expand a little more without losing the ability to penetrate reliably.

 

[vabowhntr]

How far was the doe when you shot her? In shooting the .45 cal 460 gr flat nose conical I get excellent expansion with just 70 gr of pyro p. It shoots about 1160 fps from my gun if I remember right. Was it pure lead, or was it hardened?

 

[big6x6]

I try not to worry so much about ft/lbs. of energy and worry more about bullet performance and penetration at the impact speed. In your case, the .44 cal 240 gr. XTP bullet is designed for speeds between 900 and 1800 fps. (The .45 cal 240 gr XTP/MAG is designed for 1100 to 2100 fps.) Even at 150 yards the bullet is carrying 770 ft/lbs @ 1200 fps which is still perfectly acceptable for this bullets design parameters (assuming your example of 1600 fps @ the muzzle).

My 2 cents...

tooldog

That's really my thoughts exactly. Bullet design velocity is probably more important than energy. I've killed big whitetail does with 158gr hollow-points from a .357 Magnum handgun. Shots were 40-50 yards impact ENERGY was only about 450 ftlbs. Impact VELOCITY was over 1100fps, easily within the working velocity of that bullet. So I KNOW 450ftlbs is ENOUGH, but is that PREFERABLE? Not really and we all know that putting the bullet in the right place is the most important part of the shot.