It seems no other facet of the American firearms industry changes, updates, and shifts with the constancy and consistency, as does the world of AR-15s. Calibers number in the dozens, manufacturers double, triple, quadruple that (who can keep count), and the accessories—they are ever bolder, ever more functional, ever so much more clever than the last batch. Add to that the volcanic potential of the ever-present political climate, and you have a firearms realm that seems to morph by the minute.

How does one keep up with it? How do you buy the one that’s right for you? How do you build the one that’s right for you? How do you get it ’smithed or ’smith it yourself? How do you choose between the dizzying array of accessories, and how do you tell the difference between the ones that make a difference and the ones that are just fun (or “Why bother?” for that matter).

At Gun Digest, we’re here to help. We’re extremely fortunate to have the ever erudite Patrick Sweeney, expert bar none on the AR-15 and all its detritus, as a regular and steady author with our family. His most prolific works with us include his whopping four Gun Digest Book of the AR-15 volumes. Even today, the first volume, printed in 2005, is a top seller, as are all his books on the subject, including Volume 4, published just late last year. Why? Because each is valuable and contains unique information—just right for a firearm that changes as often as you change your socks.

We’ve now collected them all in digital format in the Gun Digest Book of the AR-15 Digital Collection. Covering everything from maintenance to functionality, the latest models and all the things you could latch on to their Picatinny rails, plus tips on parts and DIY-ing this ubiquitous gun, this is the resource—four full books worth!—for anyone owning or getting ready to purchase or build an AR-15.

Click here to download instantly!