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Discussion Starter · #1 · (Edited)
If you look at the ballistic information below, you will see that a 175gr bullet has less velocity, less energy, and more drop than a 150gr bullet.
My question is, "why in the world would anybody load a 175gr projectile"? As far as that goes, why would a bullet manufacturer even offer a 175gr bullet, since the 150gr bullet is obviously a far superior pill for that caliber gun? According to the numbers, the only thing you gain from loading a 175gr bullet is a bigger bruise on your shoulder. I see this with a lot of calibers, and I always wonder why in the world anybody would load a heavier bullet if it is an inferior performer. I just don't get it.

Velocity (ft/sec)

Bullet 150gr Muzzle Velocity: 3325
Bullet 175gr Muzzle Velocity: 3025

Energy (ft/lbs)

Bullet 150gr Muzzle Energy: 3682 -------- Energy at 400 yds: 2254
Bullet 175gr Muzzle Energy: 3555 -------- Energy at 400 yds: 2047

Long Range Trajectory

Bullet 150gr Zero at 250yds / -11.4" at 400yds
Bullet 175gr Zero at 250yds / -14.5" at 400yds
 

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What caliber gun are you talking about.
 

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Is that at max velocity for the 175 grainer? Or the chrono speed for the same powder charge? I would suspect that at the same speeds the heavier bullet will have greater energy potential?
 

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Yup, you're missing a lot more info in there.
What caliber, what style bullets & their ballistic coefficients and sectional density, besides the stuff that Randy mentioned.

It looks like with the two particular loads that you're comparing, the 150gr does have the edge.
But in many instances a slightly heavier bullet will win out both in retained energy and ability to buck wind...even though the heavier bullet starts out slower.
A couple of those that I know right off the top of my head:
100gr vs 120gr (both spire points )in the .25-06 or .257Roberts is one.
Another is 150gr SP vs 165gr SP in .308Win.
 

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heavier bullets shed velocity less quickly and have more energy at equal velocities.

remember also force = mass times acceleration squared. So higher velocity tranfers more force than more mass.

this causes lighter bullets to sometimes have higher 'energy' at longer distances. But it's true performance may not be measured by merely looking at foot pounds. If the bullet penetrates and exits, you lose a ton of that energy. When a bullet stays in you, you absorb 100% of it's energy.

So 9mm vs 45.

also remember that any projectiles of equal diameter and velocity, the heavier will always penetrate more. So velocities being equal or close, the heavier bullet has a big advantage in terminal performance. Plus, like said, heavier bullets also resist wind better.
 

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Discussion Starter · #6 ·
So ballistic charts should show something other than energy, if energy is not a true measurement of terminal performance.
 

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not really, it's just a good indicator. Type of bullet (FMJ vs HP, ballistic tip, TSX, etc), diameter/caliber and other characteristics all make a huge difference.
 

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It's A measure. There are of course other metrics one can use. However; an accurate 175 grain bullet beats an inaccurate one and if your chosen rifle shoots the heavier bullet more accurately then that's the one you're gonna use. Obviously there are different platforms in a given diameter that can take better advantage of a heavy bullet too (think .300 RUM vs. 30-06 in a 200 grain bullet and you see what I mean).

Bullet construction obviously plays a role and the new non-toxic bullets throw some of the old school of thought right out the window. I shoot the Barnes bullet and find that it generally performs better in a lighter, faster loading than a heavy bullet of similar construction. In my .300 win mag I have killed mule deer and elk with the 200 gr. Accubond and the 168 gr. TTSX with almost identical terminal performance.
 

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You have much to learn grasshopper.. Have you ever seen a 150 grain bullet with a BC over .500?? I havent.. Thats why you wont see many people shooting a 150 gr bullet much over 600 yds, save for the Palma team that has to use 150 gr bullets, but they do it with 30+ inch barrels to get more speed.

Velocity isnt everything CharlesMan.

168 and 175 gr bullets is all i like to shoot in my .308
 

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Red apples don't go as far as oranges, it must be the color red. Time to review my ballistic chart.
 

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What ever you hit with either bullet, won't know the difference.

those who beat their guns into plowshares, will plow for those who didn't
 

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You have much to learn grasshopper.. Have you ever seen a 150 grain bullet with a BC over .500?? I havent.. Thats why you wont see many people shooting a 150 gr bullet much over 600 yds, save for the Palma team that has to use 150 gr bullets, but they do it with 30+ inch barrels to get more speed.

Velocity isnt everything CharlesMan.

168 and 175 gr bullets is all i like to shoot in my .308
+1 I look at the BC first if loading for longer range. The higher the BC the better flight of the bullet over long ranges.
 

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Blue Sea, you are missing this: Kinetic energy isn't the entire answer.

You said the 175 grain loading is harder on your shoulder? How can that be if the lighter bullet has more energy? You are realizing the heavier bullet has MORE energy in some manner, right?

The difference is the difference between kinetic (moving energy for lack of a better term) and momentum. The heavier bullet has greater momentum. Sort of (not exactly) like the difference between horsepower and torque in a automobile or truck.

In many instances, I'm a 'momentum' (heavy bullet) proponent.
 
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