Help with grain difference in ammunition for each caliber

[djhaycock]

Since I'm new to shooting, I'm trying to learn as much as possible. Recently I went shopping for ammo and walked out absolutely confused. I ended up buying some Federal Hydra for my XD 9SC, it seemed like a lot of people here use it.

When looking at the ammo I realize there is a difference between 115 grain, 124 etc., but what is it? What does that all mean?

Next, it seems like +P is pretty popular for home defense in 9mm as well as other calibers, what's the forums opinion of that?

Finally, are there any good books on ammunition and the hobby in general that I should be reading? What would you consider MANDATORY reading for a newbie?

Thanks.

[Fastsc92]

When buying ammmo, the grain size refers to the weight of the lead or jacketed bullet. A heavier bullet will have more energy when it hits its target.

When reloading ammo, grain refers to the weight of the powder inside of the casing. 9mm ammo can have anywhere from 4gr-8gr of powder, depending on what brand you use and how fast it burns.

+p ammo and +p+ ammo refers to ammo that produces more power and chamber pressure. (+p+ has more power than +p).

[bkelm18]

Just so you know, +p+ is not a SAAMI designation. I personally wouldn't shoot it out of my guns.

[vafish]

A "Grain" when referring to bullets or gun powder is a measure of weight.

There are 7,000 grains in a pound.

So a 124 grain bullet is heavier than a 115 grain bullet.

Here is a link to a good description of +P and +P+

http://www.frfrogspad.com/miscellk.htm#+P

[714XD]

Originally Posted by Fastsc92

When buying ammmo, the grain size refers to the weight of the lead or jacketed bullet. A heavier bullet will have more energy when it hits its target.

When reloading ammo, grain refers to the weight of the powder inside of the casing. 9mm ammo can have anywhere from 4gr-8gr of powder, depending on what brand you use and how fast it burns.

+p ammo and +p+ ammo refers to ammo that produces more power and chamber pressure. (+p+ has more power than +p).

so is there a different feel when firing between the two grain types?
would this affect sight alignment?

[fredj338]

The heavier bullet does not always deliver more energy. Energy goes up w/ the increase of vel. A 124gr+p will produce more energy than a std. vel. 147gr load. The heavier bullets will offer deeper penetration for SD. Recoil wise, the +p loads in any bullet weight will recoil more than std. vel. loads. For practice ammo, std. vel. 115gr FMJ ammo is fine.
You need to get some good instruction from a serious shooter. There are few books available & you'll have many questions. Just keep asking.

[714XD]

Originally Posted by fredj338

You need to get some good instruction from a serious shooter. There are few books available & you'll have many questions. Just keep asking.

Do you recommend any book in particular to start off with?

[agalindo]

If you want info on terminal ballistics visit this site.

http://www.tacticalforums.com/cgi-bi...ubb=forum;f=78

[Loves2Shoot]

Originally Posted by 714XD

so is there a different feel when firing between the two grain types?
would this affect sight alignment?

Yes, if you shoot a 115 grain 9mm bullet it will not impact the same as a 147 grain bullet.

[fredj338]

Originally Posted by Loves2Shoot

Yes, if you shoot a 115 grain 9mm bullet it will not impact the same as a 147 grain bullet.

Again, not necessarily. If you are talking 7yds, virtually no diff. depending on your pistol & shooting style. Out at 15yds you MAY see the heavier bullet impacting higher.
Sorry 714, there are many good books on tactical shooting but I'm not aware of any good beginners books. Hands on basic instruction would be great. Try the NRA website for instructors in your area. I used to be a cert. NRA pistol instructor. If you need some pointers or want to ask questions, shoot me a pm.