The Pouch Central Spreadsheet is the most comprehensive source of info about ammo pouches on the internet.
When I started doing carbine training I had to figure out how to navigate the large number of solutions for carrying ammo, and needless to say it was confusing. There are tons of options out there. Folks in the military and law enforcement use this stuff for work so they know this area better than a regular guy like me, but they still often have questions about specific applications. So I put together a spreadsheet to break down the different options and help people compare them.
Here's the pouch comparison spreadsheet.
The spreadsheet has separate tabs for rifle and pistol pouches. The first tab gives an overview of how to use the spreadsheet, along with definitions of the labels used in the spreadsheet. The rest of the tabs contain the lists of rifle and pistol pouches. Both the rifle and pistol pouch info is presented in two different formats: raw data, and filtered data.
If you're not very familiar with ammo pouches, start off with the raw data. It's formatted for easier browsing and helps provide a good overall picture of what's out there.
If you already know what you're looking for, go straight to the "filtered" tab. Use the dropdown menus at the top to filter the data down to exactly what you want. For example if you were looking only for Eagle duty pouches, you would choose "Eagle" from the Manufacturer column and "Yes" from the Belt Attach column.