The links below are for handgun ammo, except for the links to .17HMR, which is available only for bolt-action rifles.

General Information

Big List/Chart of Actual Bullet Sizes/Diagrams on StevesPages
The Name Game
Waterguy's Handgun Ballistics
Ballistics By the Inch (Velocities of All Handgun Ammo)
Best Choices for Self-Defense Ammo
Twoguns Guide to Reloading (Part One)
Twoguns Guide to Reloading (Part Two)
Gabe Suarez on Caliber Selection
The Myth of Energy Transfer AND the SWAG method of testing cartirdges
Italian Military Ammo and Firearms Information
Online Muzzle Energy Calculator
Handgun Trajectory Table for All Calibers
Exterior Ballistics dot Com
Ballistics for Dummies
Reloading for Small Self-Defense Concealed Carry Handguns
Old Granpa's Ballistics Forum at the USRAnge
Blazer Ammo - All Calibers -- Velocity and Drop at muzzle, 50 and 100 yards
Old Granpa's tried and true wet-pack and ballistics testing
Old Granpa's Brief History of Wet-Pack Ballistics Testing
Two Pistol Packer's Wet-pack tests for .22, .32, .380 and 9mm ammo
Cruffler's Online Muzzle Energy Calculator
Choose Your Ammo Police-Style (Ayoob)
List of Mail-order Ammo Suppliers
Interpreting FBI terminal ballistic testing data ("gelatin tests")
BrassFetcher Gel Tests on Many Calibers
ICC Frangible Bullets Tests
Ballistics Tests On DryWall (Sheetrock) Various Calibers
"Box O Truth" tests small pistols
"Box O Truth" tests small pistols part 2
Terminal Ballistics As Viewed in the Morgue
Body Armor Stops Handgun Bullets, But Not Rifle Bullets (Photos)
Glaser Ammo Discussion with Photos
Various Handgun Calibers Compared
Corbon Ballistics Info, All Calibers
Choosing A Handgun by Caliber
Handgun Cartridge Chart of Velocities/Penetration/Etc.
The Top Cartridges of the 20th Century
Federal Expanding Full Metal Jacket
Have No Faith in Your Defensive Handgun Caliber!
Gunthorp's Ammo Basics
Ammo Stopping Power/Other Specs for all calibers
GunsAndAmmo Ballistics Charts for Rifles/Handguns
Have No Faith in Any Particular Caliber
Pictures of cartridges/sizes
Ammo for Self-Defense
Speer Gold Dot Ballistic Info
Impact Force of Falling Bullets
"Stopping Power" for Beginners
Terminal Ballistics
A HARD LOOK AT HANDGUN STOPPING POWER
Pistol Ammo Ballistics from S and B
Ammo Picks for Self-Defense
Google's Directory of Ammo Makers/Sellers
Terminal Ballistics from "Steve's Pages"
TABLE OF BULLET ENERGY - PISTOL LOADS
MagSafe Negative Tests
CorBon PowRBall Review
Ammunition Articles from "Handguns"
Guns and Ammo "Let's Clean House"
Cartridge Size Measurements
Another site for cartridge measurements
Effectiveness of various calibers
Handgun Ballistics
Mini Revolver Ballistic Tables from NAA
A Wide-ranging Ballistics Discussion
Beginner's Guide to Stopping Power
Chart Comparing Handgun Cartridge Stopping Power
Speer Gold Dot Handgun Ammo Reviewed
The Fallacy of Energy Transfer
Ammunition Performance Data
Handgun Effectiveness
Recommended Ammo for Kel Tec P32
The Truth About "Cop-Killer" bullets
Personal Defense Ammunition Terminal Performance Test Data
Federal Hydra-Shok Ballistic Info
Sub-sonic ammo
Interesting Ballistics Discussion
Wound Ballistics, Step by Step
DeBunking Sanow and Marshall on Ballistics/Stopping Power
Chart Comparing Handgun vs Rife Ballistics
Kinetic Pulse Article
Rifle Ballistics Figures (You may like to compare your mousegun)
Carmon Crapson's Water Jug Tests with All Calibers
Download Ballistics Software from Stevespages

Miniatures

Miniature Calibers in German Derringers
Very Small Rimfire Ammunition
Antique Louis Flobert 5mm
Pengun, 6mm Flobert Caps or 22 Short
4mm Cartridges
6mm Flobert Short Cartridges (in Spanish language)

17 Caliber

17HMR Wikipedia Article
The .17 Hornady Magnum Rimfire
Compared: .17 HMR and .22 WMR
New NAA .17 Cal.
17HMR is Unsafe in Semi-auto Rifles
Field Testing the 17HMR
The 17HMR Forum
JesseHunting Compares the .17HMR to the .22WMR in the field against squirrels
The Magnum Rimfire Wars-.17HMR VS .22WMR

22 Caliber

22lr Velocity from Charger Barrel (10 inch)
22lr Velocity vs Barrel Length
Ballistic Gelatin Testing of Quikshok, Viper and Stinger Ammo
Descriptions of All Kinds of 22 Ammo
22LR Lethal, even at Long Range
Terminal Performance of MPB Quik-Shok, CCI Stinger and Remington Viper .22 Long Rifle Ammunition when fired from a Beretta Model 21A Handgun into Standard Ordnance Gelatin
Syd Reviews the NAA Mini-Revolver
Xavier's Thoughts: Problems with .22 for Self-Defense
.22 Pistol is Best for Self-Defense (One Man's Opinion)
WikiPedia Article on the .22 Long Rifle Cartridge
Aguila Interceptor Review
22 Long Rifle Stopping Power
60 GRAIN AGUILA AND 36 GRAIN REMINGTON 22 LR PERFORMANCE COMPARED
22 Rimfire Lethality Discussion
Early Metallic Cartridges
CCI Velocitor 40gr tests
Another CCI Velocitor Review with Test Results
Velocitor Ballistics from Muzzle to 400 yards
Velocitor Range Report
Velocitor Chronographed from Six Different Guns
V-Shrake's 22 Ammo Trials
Golden Loki's .22 Caliber Gel Tests
Six Different .22 Cartridge Styles
.22lr Subsonic Sniper Ammo (24" penetration is not born out by the GoldenLoki Gel tests-see below link)
22LR Super Maximum Hollow-Point Ammunition (1750 fps)
PMC 22 Caliber Ballistics
22 Ammunition Trials
Using a 22 for Self-Defense (Discussion)
22lr for Precision Hunting
22 Magnum As A Revolver Cartridge
22LR Gel Tests by GoldenLoki
Chuck Hawks Rimfire Articles
The .22 Ammunition Trials
Using a 22 for Self Defense
The Often Over-Looked, Under-Appreciated, Inexpensive .22 lr. Rimfires
Evolution of the Rimfire Cartridge
History of the 22 Rimfire Cartridge
Various Remington 22 Cartridges with Ballistics
22 Rimfire Cartridges/Velocities
22lr Gel Tests by GoldenLoki
22 Best for CCW
CCI 22 caliber ammo
Thirty Four .22 Ammo Discussions
22 Stopping Power
Complete Rimfire Ballistics Table
22 Rimfire Ballistics Tables
(SubSonic Sniper) 22LR Ammo

22 Winchester Magnum Rimfire

Wikipedia Article
Oldgranpa's 22 Magnum "Ballistics Blog"
Pistol packing Maggie: Winchester's Magnum rules
22 Mag in Revolvers
The .22 WMR TODAY (James)
Carrying a .22 mag for Self Defense
22 Magnum pistols and ballistics info
The Sleeper (22 mag)
22 Mag Discussion
NAA Black Widow .22WMR -vs- Wet Newspaper
More 22 Magnum Wetpack Tests
The 22 Magnum Cartridge (Chuck Hawks)
Many 22 Magnum Cartridges (Ballistic Info)

25 Caliber

Speer Gold Dot .25 Expansion Ammo Test Video
.25 ACP Wikipedia Article
.25 ACP (6.35mm Browning) Ammunition Performance Data (Firearms Tactical Institute)
Gun Nuts Comments on the .25 ACP
.25 ACP Terminal Ballistics (What Would John Wayne Do?)
Lengthy .25 acp discussion on defensivecarry.com
Dan Johnson's Article Comparing .25 to .22... PDF format with color photos
25ACP Performance Data from "Steve's Pages"
25 vs 22 Discussion - Which is Better? .25ACP Gelatin Tests
.25 ACP Berreta 21A Pistol in Ballistic Gel
Casting .25 Bullets, and Loading your own .25 Ammo
Re-Loading data and dimensions for .25 ACP (.25 Auto) calibre

32 Caliber

Ranch Dog's Ballistic Info for .32 and .380
.32 ACP Hollow Points from a Kel-Tec P32
Wetpack/Water Tests with a Kel-Tec P-32
The Resurgence of the .32 ACP
Brassfetcher's .32 ACP Gel Tests and Information
32 ACP Data from Ballistics 101
WikiPedia .32 ACP Article
Chronograph Results Comparing .32ACP, .32NAA and .380
32 Caliber Ballistics, Various Ammo Makes
32 Caliber Shootout - Four Different Guns
32 Caliber is Under-rated
32ACP Gel Tests by GoldenLoki
NAA .32 mousegun ammo
32NAA Ammunition
Kel-Tec P32 gel tests, etc.
32 Magnum Ballistics
32 ACP Kel-Tec, NAA Guardian and Beretta

380 Caliber

.380 Penetration Tests in Various Materials
Brian Orr Tests the .380 in Meat
The Elsie Pea (Ruger LCP) Forum has Many Links to .380 Ballistics Info
Gun Tests Magazine tests six varieties of .380 ammo
Oldgranpa's truly final wetpack test to compare .380acp penetration of Speer GoldDot and Federal HydraShok ammo
Brassfetcher's Extensive .380 Tests (PDF Format)
LEO "Erich" Recommends .380 Ball over Hollow Point, for Self-Defense
Brass Fetcher Tests Golden Saber .380 ACP in Ballistic Gel
Stephen A Camp Reviews Hornady Critical Defense Ammo
Steve's Pages (Updated 10/30/2009)
Oldgranpa's Goldensabr Velocity Tests and Chart at KTOG
Hornady Critical Defense Results and Photos at KTOG
.380 Data Links at the ElsiePea Forum
Article about .380 "kabooms" in Ruger LCP and possibly Kel-Tec P3AT
What is "Santa Barbara" 380 ammo?
Vectrexer Tests Various 380 ACP ammo (for feed and function) in two Kel-Tec P3AT pistols
Oldgranpa's Kahr p380 tests (phase #1)
Oldgranpa's Kahr p380 tests (phase #2)
GoldenLoki's Recent .380 ACP Gel Tests
GoldenLoki Reports on Smiley Face Preventing Expansion in .380 HP Ammo
Old Grandpa's AMT clone second chance test
Old Granpa tests the Ruger LCP
Gelatin Penetration Tests (Brassfetcher)
Big Chart of .380 Cartridges
Bobo's Big List of 380 Test Links
OG and F&S Test Varieties of Ammo in the AMT380
Old Granpa's Comments's on DoubleTap .380 ammo
DoubleTap .380 (OG's report on the Seecamp Forum)
DTWilly Tests DoubleTap 380 ammo
Oldgranpa's Bersa vs KelTec Shootout
Seecamp 380 Bone Test
380 Velocity Testing
Wetpack test of 380 DPX by "Dipped"
Nov. 2006--"Oldgranpa" does wetpack tests of .380 ammo in an NAA Guardian
Corbon DPX .380 tested in a Bersa .380
Rohrbaugh R9S / Seecamp LWS380 Shoot-outVarious Ammo Tested
Same Report with Other Pix and Comments on the Seecamp Forum
DTWilly Compares Corbon DPX to Ranger T Ammo
380 DPX Tested on A Raccoon
DT_Willy's Wet Newspaper Tests on DPX 380
Flyandscuba's DPX tests in the Seecamp LWS380
Corbon DPX 380 Gel Test Results
380 Wetpack Tests with Bersa (includes Corbon DPX)
Old Granpa's Truly Final .380 Wetpack Tests (with a Sig)
Old Granpa's Truly Final Tests with comments by Stephen Camp
Why the .380? (American Rifleman)
38 Special or .380 ACP
Winchester Ranger 380 Remarks
Corbon DPX Reviewed by Stephen Camp
Corbon Powrball in .380 Tests
380 Ammo Discussion
Makarov vs 380ACP
380 Santa Barbara and D. Nobel Chronographed
Santa Barbara Ammo Dissected, Weighed, Measured, etc!
Santa Barbara 87 grain 380 tests
Corbon 380 DPX tests (80 grain)
Corbon 380 Powrball tests (70 grain)
KTOG Discusses Corbon DPX and Powrball
380 Powerball vs FMJ test in wet paper
Popularity of the .380 is Great
GlockTalk Discussion on Best .380 load
Corbon DPX 380 tested in a Bersa
Kel-Tec P3AT testing ammo in gel
380 Defense Loads Discussion
380 Performance from "Steve's Pages"
380 Guardian Velocity Tests from NAA
380 Discussion
380 Performance Data
380 ACP discussion
Best ammo for Kel-Tec P-3AT
380 vs 9mm for Self-defense
Winchester 380ACP varieties
+P ammo for Kel-tec P3-AT
380 and 9mm in Wet Phone Books
GoldenLoki's 9x18 (Makarov) Gel Tests
Bobo's Huge List of Links to .380 Ammo Tests (on KTOG)

38 Caliber

38 Special Snubby Ammo
Pocketful of Dynamite
AMMUNITION BALLISTICS FOR: .38 Special (RifleShooter Magazine)
Ballistics Chart from Guns and Ammo Magazine
Wikipedia Article on the 38 Special
Firearms Tactical Institute Tests of the 38 Special
.38 Special (Vented Barrel Ballistics) From Sportsmans Guide

9mm Caliber

Note: 9mm is about .354 inches

Cheap Ammo (9mm) -- Testing for Accuracy
9mm Water Jug Testing of A Variety of 9mm Ammo
Winchester 127-gr. +P+ (RA9TA) ultra speedy 9mm load
Kahr PM9 Wet Pack Ammo Comparisons by JGRider on the USRAnge
Rohrbaugh R9S Range and Ammo Comparison Report
More Rohrbaugh R9S 9mm Ammo Testing
Bonded Golden Saber in 9mm through gallon milk jugs
9mm Velocity Testing on Many Brands
History of the 9mm Cartridge (Long and many pictures)
Long/Good Discussion on Effectiveness of 9mm Ammo
Corbon 9mm 115-gr. DPX +P--(Fired from Browning Hi Power w/factory barrel, w/Barsto barrel, and from Glock 26)
J.P's 9mm Wetpack Tests (Many Brands)
Firearms Tactical 9mm Ammo Performance Tests
The History of the 9mm Luger Cartridge
Photo of 8 Different 9mm Cartridges
9mm speed tests in a Kel-Tec P-11
9mm Ballistics Wetpack Testing
9MM Gel Tests by GoldenLoki
9mm vs 380 (compared)
380 vs 9mm for Self-defense
9mm ballistics discussion
9mm stopping power
Kel-Tec P11 9mm gel tests many ammo varieties
Rohrbaugh R9 Ballistic Tests
9mm High Power Velocities
Corbon PowrBall 9mm 100 grain Ballistics
9mm Aguila Ammo Velocity/etc.
9mm Various Manufacturers Performance Data
Why the 9? Advocating the 9mm cartridge
9mm Ammo Recommendations (Discussion)
9MM Ballistic Info, shot from a Rohrbaugh

357Sig

357 SIG Article from GunWeek
Pete's 357Sig Page (Lots of Info)
A 357Sig Advocacy Page

.40SW Caliber

Flyandscuba's DPX Testing/RangeReport
Gun Tests Ballistic Data from Three Compact .40's
.40 S&W Performance Data
Is .40 better than 9mm?
Extensive Ballistics of 40SW from 4.5" and 16" barrels

.45ACP Caliber

Discussion of Various .45 ammo from a "short barrel"
Kahr P45 / Taurus PT745C Shoot-out and Wet Pack Test
45 Caliber Advertised Velocities
Taurus Hex and Other .45 bullets (see photos)
The Jethro Bodine Ballistics Lab tests 45 ammo

Ammo Sales/Manufacturers

ExtremeShock Ammo
TargetSportsUSA
Bulk Ammo
Alamo Ammo
Blue Bunny Ammo
LuckyGunner.Com (All Ammo in Stock, and Ready to Ship!)
Ammunition to Go (in Texas)
Polywad Shotgun Shells
Triton Ammo (QuikShok, Hi-Vel, etc)
SouthernOhioGun
PMC Ammo
CCI Ammo Company
22ammo.com (22 ammo for sale)
Cabela's Handgun Ammo
Cabela's 22lr bulk ammo
AIM SURPLUS Low Cost Ammo
The Ammo Bank
Ammo Direct
Speer Ammunition Company
Winchester Ammunition
Buy Ammo at "The Armory"
Natchez Shooting Supply
Cabela's Handgun Ammo for sale
Sellier and Bellot USA
MagSafe Ammo
Chestnutridge Ammo for sale
Dan's Ammo for sale
The Ammo Man
RBCD Performance Plus Ammo
RBCD Ammo
Cheaper Than Dirt Ammo
Corbon Ammo Company
The Federal Cartridge Company
Remington Ammo Company
MidwayUSA Ammo For Sale
Hirtenberger Ammo
Wolf Pistol Ammo
DoubleTap Ammo