ARP 030 - How it's Made | AR-15 Barrels

Reed takes you on an in-depth journey discovering how a rifle barrel is manufactured.

Welcome to episode #30 of the AR15 Podcast.  I’m your host Reed Snyder and tonight I will be trying my first solo show. This is THEE podcast about your favorite black rifle! This show is for you; whether you're building your first AR or you’ve been building AR’s for years. There’s something we can all do to take our black rifle to the next level.

BREAKING NEWS: Otis has signed on to provide us with 3 months of weekly giveaways of their BONE tool and bottles of their O12 carbon remover.  And Steve has reported to me personally that the giveaways have arrived.  We will start our weekly giveaways next week and all you need to do to get a chance to be considered for a give away is to write in to the show at or  Please visit Otis Technologies at for all of your gun cleaning needs.  Make sure you tell them you heard about them from the AR15 podcast and the Firearms Radio Network!

OTHER BREAKING NEWS:  I am an idiot.  I have been telling you, our faithful listeners that my email address was  I was wrong.  It was brought to my attention that my emails was  Management has seen fit to create an account for so it works now.  Just another example of the fact that we are all human here at the Firearms Radio Network, some more than others.  However, since you may have sent me an email that did not make it through, I would encourage you to send it again and I apologize if you thought we were ignoring you personally.  We try to bring your emails up in the shows and if we can't, we try to send personal responses.  So, please try again.

AR-15 Training Tip of the Week:

By  Adam Heggenstaller

Modified Navy Qualification Drill

The drill was developed by former Navy SEAL Jeff Gonzales.

The MNQ Drill is intended to be shot with an AR or other semi-automatic. The MNQ Drill incorporates three firing positions, magazine changes, some movement and a timer to add a bit of stress. There’s a lot going on in this drill, but you’ll need only 15 rounds to shoot it.

Place a target with an 8-inch center zone at 50 yards. (A paper plate stapled to the chest area of a silhouette target works great.) Load three magazines with five rounds each. At the firing line, assume a low-ready position with the rifle loaded. When the buzzer sounds, fire five rounds from the standing position. Reload, and fire five rounds from the kneeling position. Reload again, and fire your last five rounds from the prone position. The clock stops when you fire your final shot from prone.

The par time for the MNQ Drill is 25 seconds, and only hits in the 8-inch target zone count. You start with a score of 0, and are penalized for misses and time over par. The goal is to keep your score as low as possible. Add 5 points for every miss and 2 points for every second over par. Subtract 1 point for every second under par. For example, if you shoot the drill in 35 seconds with two misses, your score would be 30—20 points for the 10 seconds over par and 10 points for the pair of misses. If you shoot the drill clean in 22 seconds, your score would be -3.

Gonzales is the president of Trident Concepts, a training academy based in Cedar Park, TX, and he uses the MNQ Drill to gauge the skill level of both his students and instructors. To qualify as a marksman, a student must score 25 to 40 points. A good goal for beginners is to make the 40-point cutoff, keeping in mind each miss hurts the score more than each second over par. At Trident Concepts, a score of 10 to 24 qualifies you as a sharpshooter. To make the expert level, you’ll need a score of 9 or lower.

Main Topic: AR-15 Barrels in Depth

  • How it’s manufactured
    • Bar Stock
    • Drilling the Bore
    • Reaming
    • Rifling
    • Profiling
    • Lapping
  • What it’s made of
    • 4150 Chrome Molybdenum
    • 4140 Chrome Molybdenum
    • 4340 Chrome Molybdenum
    • 416 Stainless
    • 410 Stainless
  • How the rifling is formed
    • Cut Rifling
    • Button Rifling
      • push
      • pull
      • Hammer Rifling
  • Special production processes
    • Heat Treating
    • Cryo Treating
    • Barrel Linings
      • Chrome
      • Nitride
      • Melonite

Listener Feedback:

DRD: One of the people writing in had asked about an "M4Chart" that was previously referenced.  I think he may have been referring to this:

Explanation of Desirable Features in Commercial M4 Pattern Carbines

I hope that helps,

Thomas G: Hello Gents, I just wanted to thank you for giving me the nudge I needed to build my first AR, I decided to chamber it in 300 AAC Blackout.  My build was based on market availability as much as chosen items (a Frankenstein to an extent).  Overall I am happy with the quality and progress made so far.  I will be able to shoot it soon, and as time goes by I will replace some parts as the ones I want are becoming available on the market and prices are stabilizing a bit.

Components so far are;

CMT TAC Billet Lower

Yankee Hill Machine Billet Upper (market availability) - When CMT TAC comes out with their upper, I like the quality of CMT TAC and will be replacing the YHM upper.

Rock River Arms Mil Spec BCG (market availability)

BCM Mod 4 Gunfighter Charging Handle

BCM Mil Spec Buffer Tube

Magpul Mil Spec ACS Stock

DMPS Trigger Kit (market availability) - I would like to upgrade in the future Geissele Super Dynamic Enhanced

Wilson Combat 16" 1:8 Barrel

Troy Low Profile Gas Block

I am still deciding on what type of rail system.  I was thinking of going with a free floating mid length Troy STRX-AL1-00812699014684  11" Alpha Rail with the integrated flip up sight.  What are your thoughts on this?  I will be purchasing an AAC  BLACKOUT 18T Flash Hider.

Keep up the great work.


Bryan Bolivar: Yet another response to rifles that can be used in Canada for hunting and accept AR-15 rifle mags. Besides the previously frequently mentioned Mossberg offering, there are numerous other rifles that are classified as non-restricted in Canada and as such, can be used for hunting

Robinson XCR

Benelli MR1

Swiss Arms (with lower conversion kit)


Remington 7615 pump action

This is off the top of my head, I think there are one or two others. Yes, that's right, there are several semi-automatic rifles that are considered non-restricted and are good to go in Canada for hunting but the AR-15 is restricted and limited to approved range use only.  What can I say? Canadian gun laws, like those in most countries, don't have to make sense. They just have to suck, eh! The listener could check out Canadian Pro-Gun forums like Gun Owners of Canada and Canadian Gun Nuts to get some more information.


Bryan Bolivar

Canadian Service Conditions Radio

iTunes Review:

Plate Carrier Giveaway:

Let me know why you think you need a new plate carrier, send me a picture via email showing me the sad state of your current plate carrier to to enter our drawing for a brand new (with tag still attached) Condor Compact Plate Carrier in Coyote Tan courtesy of Brad from the FRN IT Team.