Bullet weight vs. velocity and energy

[Karl Blanchard]

I have been pouring over ballistics charts and comparing loads and data.  I was always kind of blindly under the impression that a big heavy bullet hits harder than a lighter bullet.  My 06' with a 150gr bullet leaving the muzzle at 2950fps has more foot pounds of energy than the same bullet in 180gr with a muzzle velocity of 2750 fps all the way out to 400 yards!  So which bullet hits harder.  This was the norm for all calibers I cross checked Velocity beat weight for energy everytime.  I am going on an Alaska coastal black bear hunt next spring and am trying to decide on a load.  Right now I am shooting the 150gr interbond moving at the above velocity.  Just curious what people that know a lot more about the subject than I do think.  Seems pretty clear cut to me, a solid bonded bullet that has more energy is gonna hit harder than a heavier one with less energy. The only problem I could see is a lighter bullet would lose energy faster on impact than a smaller one.   Thanks in advance.

[yorketransport]

I'd say go with the 180gr bonded bullet of your choice. The heavier bullet will have a better sectional density, and theoretically penetrate better. Ft/Lbs of energy can be a misleading number. A 243 with a 100gr bullet at 3100fps has 2135 fpe at the muzzle. A 45-70 with a 300gr bullet at 1800fps ( a mid level lever action load) gives you 2155 fpe. Which would you rather use?

Andrew

[Skycruiser]

A 150 gr. and a 180 gr. are both going clear through a black bear if your shot is ok. I would tend to go with the 150 though either one will do fine.

[Curly]

I'd say a 165gr is just about right in the 30-06.  It is a good compromise between the speed of the 150gr and the weight of the 180gr.  And the BC will be better with the 165 than the 150, which may help it buck the wind slightly better than the 150gr........

[bobcat]

Foot pounds of energy is a useless number that means nothing. What is your definition of "hits harder?"  A heavier bullet will generally penetrate more than a lighter bullet. But yes, the lighter bullet generally will be going faster, thus "hitting harder." It used to be that with most conventional bullets the heavier bullet would almost always be a better choice if you were after big, tough animals. Now with the bonded bullets and pure copper bullets that shed very little weight, it's kind of a toss up. I would say go with the bullet that shoots best in your gun. If a 150 grain bullet shoots good then that's a bonus, as you will have less recoil than with a 180.

[Intruder]

Agree with everyone here about ignoring the ft pounds energy.  As for what will be better out of you gun, it is safe to say that anything from 150-180 will be more than adequate at killing a bear.  First and foremost use a good quality bullet.  I'd likely shoot 165s or 150s just to get me a little flatter shooting load.  180s in an 06.... is kinda of a lobber.  However, if you're shots are under 200 no biggy.

[JackOfAllTrades]

The only problem I could see is a lighter bullet would lose energy faster on impact than a smaller one.

BINGO! You answered your own question.

Although there have been a lot of Bear killed with the 165gn bullet, like Curly suggests...  The Bear I could not recover was hit with a couple of well placed hand loads (165gn quality bullets), that were Screemin from my Ought-6.  I've since taken a Bear at closer distance with 180gn bullet. Although, shots were through and through with that one. All you're doing by pushing that 165 to high velocity is turning your 30-06 into a 7rem mag. -This is surely going to spawn a 'little bullet going fast vs a heavier bullet going slow' argument. (I hope not though)

Coastal Blackies in AK are bigger and tougher than our 250 pound non-threatened bruins around here. I'd go with the most accurate 180 your gun shoots and still push'm as much as you can for the first three shots in the magazine. I keep the last shot as 190 or 200gn for when I'm walking up to the dead animal. If he stands up.. Even twitches an eye lash.. Bam!  -Just my opinion. As any game that can bite.. I hit with as much gun as I've got available.

-Steve

[whacker1]

coastal blackies in Alaska are generally short range, so I wouldn't be evaluating the over 400 yard scenario.  I generally shoot the bullet that shoots best regardless of weight of bullet.  But when I was in Alaska on Prince of Whales Island, you could lose bears if they got into the brush purely, because the brush was too dense to follow.  So knowing what I know now, I would shoot the best 180 or even look toward the 200's or 225 bullets if you can get them to shoot, because balistics won't be an issue at short range.  I would prefer that 225 knock them down, and that they don't have a chance to get into the thick brush.

I shot my bear at 25 yards with a 130 grain bullet out of my 270 in the lungs, and the again in the back and heart on the second shot @ 35 yards, and it dropped.   Had it gotten past another 5 yards, I wouldn't have been able to follow it. 

[Intruder]

I'm not sure I agree that you have to shoot bigger bullets to anchor an animal.  A well placed shot in the shoulder w/ a bonded bullet or something like a barnes will anchor it just as well as a bigger bullet.  In fact it's the shot placement that accounts for 95% of it.  A lung shot regardless of bullet size is likely to result in the bear making it at least a short distance. 

[bobcat]

I also don't think there is much advantage to heavier bullets, other than the higher BC's sometimes provide better trajectories and less wind drift at long range. A heavier bullet will generally penetrate further than the same bullet in a lighter weight. But if you're shooting a good bonded bullet, or a 100% copper bullet, then penetration isn't going to be an issue. I think especially with a bullet like the Barnes, you're better off on the lighter side as you will likely get slightly better bullet expansion due to the higher impact speed. With the bonded bullets I'd probaly go 165's in the 30-06 and with a Barnes I'd go with 150's or 165's. If you're using a cheap bullet like a Core-lokt, or even a Partition, then I'd want a 180 grain.

[Karl Blanchard]

i appreciate the input.  You hear so much argument on the topic and everyone has their own opinion.  I'm thinking I need an Alaskan bear gun.   Good excuse to buy an X-Bolt!

[Bob33]

My 06' with a 150gr bullet leaving the muzzle at 2950fps has more foot pounds of energy than the same bullet in 180gr with a muzzle velocity of 2750 fps all the way out to 400 yards! 

Not sure how you came up with that, but I don't compute it that way.

Foot pounds = ('bullet weight in grains' x 'ft/sec' x ft/sec') / 450400

A 150 grain at 2950 ft/second has about 2900 ft/lbs of energy at the muzzle.  A 180 grain bullet at 2750 ft/second has about 3025 ft/lbs of energy at the muzzle.  If the ballistic coefficients are the same the 180 will always have more energy than the 150 with these given muzzle velocities, and 180 grain bullets typically have a higher ballistic coefficient than 150 grain bullets.

[Jamieb]

This tread has made up my mind, I need big and fast. 378WBY for yotes and a 460WBY for big game.

[257 Wby Mag]

Check your PM Jamie, let me know if you got the pics. Later

[257 Wby Mag]

To steal one from F%@k Stick, "Fret the boolit, not the chambering"......