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Discussion Starter #1
Any one know any websites that explain more about ammunition. I am a little new to buying ammo and don't know much about it. I'm looking for a site that explains about the difference in grain etc..

Thanks for the help
Jason
 

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A grain is a measure of weight. There are 7000 grains in 1 pound. As to your first post more specific questions might help get responses. What cartridge are you looking at, what gun, and for what use?

mcb
 

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Discussion Starter #4
I guess that would help huh. I am looking for mir information on 9mm ammunition. I read a lot on this forum about different grain. I was wondering what the difference is. I understand there is a power difference, but what is more powerful?
thanks
Jason
 

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I figure you're comparing factory ammo. There are web sites for each ammo manufacturer that will give you ballistic specifications for their ammo. Check out Winchester, Federal, CCI, etc.

Normally you'll find on the ammo box the weight of the bullet expressed in grains, velocity at muzzle in feet per second, and energy at muzzle in foot pounds. There is an equation to calculate this energy if your pistol produces a different velocity as the manufacturer nomally tests their ammunition in a barrel of a specific length. Manufacturer's specs will tell you this. Example: 9mm is normally tested in a 4" barrel.

You will note that bullets with the same weight but traveling at different velocities will have different energies.

Here's the equation: bullet grains x velocity squared /450400 = 115 gr x 1280 fps x 1280 fps / 450400 = 418 ft lb.

Manufacturers will produce different types of ammo by using different powders and different amounts of powders. To further the confusion you'll find ammo that's marked +P and +P+. These cartridges will exceed normal cartridge pressures. Please ensure that your pistol can handle these cartridges or you'll end up with a KaBoom.

For premium ammo checkout at Cor-Bon ammunition at www.corbon.com
Their self defense ammo for 9mm+P 115 gr JHP develops 1350 fps and 465 ft lbs.

Hope this helps.
 
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