I'm so confused it's unreal. What do all the numbers and jargon mean? 30-30, 30-06, .308, 7 mm, WSM, ultra mag etc... I can't make since of it all. Do they make a balistics for dummies book? If so I'm buyin. I checked with a friend who has been an avid hunter for over 30 years and he couldnt tell me either. So can anyone here explain all this to me?

Buy a good reloading manual. Within its pages is everything you could hope to learn about guns, Ballistics, bullet construction and the whole nine yards. I like the two book set from Hornady. Manual one has the write ups and loading data and book two has all the ballistics charts and tables.

Excellent advice James...

You have to "read" what each one stands for, as there no rymn or reasonfor the names of many of them. (nothing you can relate to that is) You just have to get a book like was said and read about each one.

For instance, the 30/30 stands for a 30 cal bullet with 30 grains of black powder behind it! No, no one uses blk powder today in a 30/30. The 308 Win. stands for .308 being the bullet diameter in inches, and Win. is Winchesterwho put it on the market as a standard round.

And on it goes.............

Drilling Man

and then you take the 30-06... 30 caliber (.308) and invented and put into service in 1906... yes it can be very confusing if you've never taken the time to investigate it, etc... then folks started necking the 06 up and down and you ended up (and bumping shoulders so you can't load the wrong round in the wrong gun) with the likes of the 25-06, 270 Winchester, 280 Remington (also know as 7mm Remington Express), 338-06, 35 Whelen, 375 Whelen, 400 Whelen and probably a lot of others...
you really want to be confused... take 38 special and 357 magnum... you can fire both from a gun chambered for 357 mag but the bullet diameter is actually .357 or .358 (yes they do vary depending upon manufacturer and what not)... and the 44 mag bullet is actually .429...

reloading manuals have short write ups about just about every common round and blueprints of the cartridge along with loading data... invaluable to many people... i highly recommend spending the 30 or 40 bucks...

Rather than buying a handloading manual, get a copy of Cartridges of the World. Probably the best basic reference to current, obsolete, European, and military cartridges you can find.

I agree get this book, or a relaoading manual, they'll teach you a lots! Theres not much of a standard for caliber identification!
For instance, most double numbers, in older cartridges meant caliber, first, and then powder charge. Many of todays designations, first number is caliber, second is the "parent case caliber!"
Another good example is, "when is a .30 caliber, not a .308? When it's a .303, then its .311! whew-wee!!!!
With no real standards its confusing! Those manuals make for good reading and much learning!

More confusion: The .222, .22 hornet, .223, .22-250 all have a diameter of .224 inches!![8D]

Add to the confusion...early .22 Hornets used .223 diameter bullets. And the .22 High Power (Savage) uses .227 or .228 bullets. Buy a reference!

Don't give up hope though, once you learn some of the foundational stuff you can generally fill-in the gaps. Like the 30-06 and the 25-06...you can make a safe *guess* that it is a 30-06 (7.62X63) necked down to a .25 bullet. Also, a note of interest that has already been addressed: a .44 magnum actual shoots a .429 inch bullet and many other calibers only get "close" (You'll find that marketing has alot to with catridge names...if the competitors already make a 25 magnum...well then lets make a cartridge that shoots the same bullet and call it a a 250)
For a quick reference something that helped me mentally compare cartridges is to learn metric to standard:
8.60mm=.338
7.62mm=.308 or 7.62X51 (which is also all/most the .30 caliber bullets including all the 300 magnums)
7mm=.284 (or the .280...a necked down 30-06)
6.5mm=.260 (i think*)
6.16x51=.243
5.56X45=.223