Bullet grain help?

It's the weight of the bullet, bigger grain is heavier, therefore harder hitting (more recoil) and more stopping power. The best way to figure which is best is to experiment, as long as your gun can handle the grain of the bullets you use.
 
The grain is the weight of the bullet. A 115 grain bullet is lighter than say a 124 grain bullet. Weight helps with shot placement, and I imagine it could help with hitting power too.
 
rotncore said:
gushulak said:
I agree with all except the stopping power part of it.
Click to expand...

True, I guess mushrooming and bullet construction makes the difference. The heavier bullet will exert more force on the target on impact though.
Click to expand...

Not true. Kinetic Energy = 1/2 Mass x Velocity squared. Any increase in mass (bullet weight) is linear wheras any increase in velocity is exponential. That's to say, if you double the weight of a bullet, the kinetic energy is doubled. But if you double the velocity, the kinetic energy is quadrupled....
Click to expand...
 
Dragoon said:
rotncore said:
gushulak said:
I agree with all except the stopping power part of it.
Click to expand...

True, I guess mushrooming and bullet construction makes the difference. The heavier bullet will exert more force on the target on impact though.
Click to expand...

Not true. Kinetic Energy = 1/2 Mass x Velocity squared. Any increase in mass (bullet weight) is linear wheras any increase in velocity is exponetial.
That s to say, if you double the weight of a bullet, the kinetic energy is doubled. But if you double the velocity, the kinetic energy is quadrupled....
Click to expand...

Also, if you triple the velocity, the bullets *climb* out of the barrel. :p :p
Click to expand...
 
lighter bullets always have more energy then heavier once, but heavier bullets might have better penetration.

Dragoon, your formula is for Joules not for ft-lb! And you have to use Kg for mass vs grains, and velocity in m/s vs. fps. if you want to get energy in ft-lb and want to use grains and fps numbers. use this formula ME= mass x velocity^2 / 450400
 
IM_Lugger said:
lighter bullets always have more energy then heavier once, but heavier bullets might have better penetration.

Dragoon, your formula is for Joules not for ft-lb! And you have to use Kg for mass vs grains, and velocity in m/s vs. fps. if you want to get energy in ft-lb and want to use grains and fps numbers. use this formula ME= mass x velocity^2 / 450400
Click to expand...

The units of measurement are irrelevant. The formula remains KE = 1/2 Mass x velocity squared
 
So I got a price from Wolf. I was thinking their 124 grain full metal jackets. Would this be a good idea to shoot through the Beretta. I'll be buying a 1000, so I wanna be sure it'll be good for me....
 
The units of measurement are irrelevant. The formula remains KE = 1/2 Mass x velocity squared
Click to expand...
Don’t want to turn this into physics class but you’re wrong; :|

It is relevant what measurements you use, have you tried the formula? When using your formula you can’t use fps or grains.

OK let’s see 124gr 9mm @1100fps, so 62 (½ of 124) x 1100 ^2 =75020000 :shock: does this look right to you? Is that in ft-lbs? BTW the result should be 333ft-lb :wink:
 
IM Luger : the formula you are using has the 1/2 mass built into the constant of 450400. This is a "derived" formula. The actual formula remains KE=1/2m*v^2

Using your example:
124gr 9mm @1100fps
Click to expand...

where:

124gr = 8.04E-3kg
1100ft/s = 335.28m/s

KE = (8.04E-3kg/2)*(335.28m)^2
KE = 451.89 Joules

451.89 J = 333.32ft/lbs

So, you are both right. :wink:
 
You must log in or register to reply here.
Back
Top Bottom