Letter Re: Advice for an M4 and AR-15 Newbie

Hello JWR:
I recently bought my first AR-15[-family firearm], a Lewis Machine and Tool (LMT) Defender Carbine. I was wondering if you had any advice as to a good starter “book” on the AR generally, but also one that would assist in my rifleman’s training. I am an intermediate shooter on rifle, but am finding the AR to be a beast unto itself as far as “how” to shoot it.

Can you recommend any text on complete takedown, best cleaning practices, replacement parts, and marksmanship with the M4 version of the AR would be very helpful. Thanks! – JB in Michigan

JWR Replies: In terms of field stripping and general maintenance, the Army’s old standby M16 User Manual (M16A1 Rifle Operator’s Manual TM 9-1005-249-10 ) will suffice, but it is so simplistic (small format, and little more than a glorified comic book) that it is probably not worth paying more than two bucks for one. Look for these in bargain bins at gun shows. OBTW, I noticed that it is also available as a Kindle book for 99 cents.

The US Army’s M16/M4 marksmanship manual is available for free download. FM 3-22.

Walt Kuleck and Scott Duff’s The AR-15 Complete Owner’s Guide: (AR-15 Guide Volume 1) is a bit dated but still quite good, and discusses spare parts. (Note: Although I authored the chapter about AR-15 magazines that is included in this book, I do not earn any royalties from the publisher. (That chapter was based, with permission, on my AR-15.M16 Magazine FAQ which I make available free of charge.) OBTW, Walt Kuleck and Clint McKee also authored a companion AR builder’s guide, which is particularly useful in these times of scarcity: AR 15 Complete Assembly Guide (AR-15 Guide Volume 2)

You might also look for a US Army armorer’s manual: Rifle, 5.56MM, M16A2 W/E/ Carbine, 5.56MM, M4 Unit and Direct Support Maintenance Manual TM 9-1005-319-23&P

Note: In hard copies, army field manuals (FMs) and Technical Manuals (TMs) are fairly expensive to mail order, but they are often available inexpensively in PDF format in compilation CDs from folks like Survival eBooks. As I recall, this compilation CD includes FM 3-22.

In terms of weapons handling and tactical use (fire and maneuver), I strongly recommend getting a copy of The Art of the Tactical Carbine DVD. (At first glance, this DVD might look like just a promotional piece for Mag-Pul, but there are actually some real gems included!) I also recommend the book “Some of the Answer: Urban Carbine” by firearms trainer and M4 guru Jim Crews.

Spare Parts:
Ideally, it would be best to a have a complete spare carrier assembly, to provide a quick “in the heat of battle” replacement in case you break a firing pin or extractor, or you have the misfortune to gall an ejector. In-the-field swaps are possible because 99% of AR-15 bolts are “automatic headspacing”, if the bolt and barrel are both made to proper specifications. Hence bolts or complete bolt carrier assemblies are drop-in replacements. If you are on a tight budget, get just one each of these critical high breakage/high loss subcomponents from the bolt carrier group:

  • Firing pin
  • Firing pin retaining pin
  • Ejector
  • Ejector spring
  • Ejector retaining pin
  • Extractor
  • Extractor retaining pin
  • Extractor spring (with nylon insert)

The only other parts that I’ve seen break (or get lost) are ejection port cover springs and buffer retainers. However, both of those are non-critical to the function of the rifle. Buttstocks and handguards also break. (Albeit, less frequently). If you have a generous budget, get spares of all of those in addition to a complete spare bolt carrier assembly, and perhaps even a complete spare lower parts kit (“LPK”).