Getting Started 

U.S. Rifle Owner’s Manual


These four are the bedrock upon which firearm safety are built – anyone telling you different needs a karate chop to the neck:


KEEP YOUR FINGER OFF OF THE TRIGGER UNTIL YOUR SIGHTS ARE ON TARGET AND YOU ARE READY TO LAUNCH ROUNDS DOWNRANGE  (Imagine every bullet you fire has a tiny little lawyer attached to it. Because it does.)


BE SURE OF YOUR TARGET AND WHAT IS BEYOND IT, IN FRONT OF IT, AND ON EITHER SIDE OF IT (Remember – if you carry a loaded gun, the whole world is downrange. Act like it. )

Congratulations on your new firearm purchase!

We’ve put a lot of effort into delivering a package that will give you confidence and satisfaction in your investment.

To help you get started we have prepared the following guide.

Familiarize yourself with the controls and operating mechanism.

Once you have identified everything we can begin a safe inspection of your gun, and get ready to hit the range.

Left Side:

  • Safety aka Selector
  • Charging Handle Latch
  • Bolt Hold Open or Bolt Catch

Right Side:

  • Ejection Port Door/Ejection Port
  • Magazine Release


  • Trigger
  • Stock Release
  • Charging Handle
  • Magazine Well

Your first order of operations is to:

  1.    Lock the bolt to the rear to verify the gun is unloaded. 
  2.   Eject the magazine if in your haste you inserted one
  3.   Then, release the charging handle and pull that sucker all the way to the rear with your right hand. With your left, press on the BOTTOM of the Bolt Catch which should then hold the bolt after you release the charging handle. 
  4.   You can push the charging handle back into place
  5.   An alternate method for the less dextrous is to insert an EMPTY magazine and then pull the charging handle to the rear. The follower on the magazine will automatically engage the bolt catch. 
  6.   Once your bolt is locked to the rear, look into the ejection port and verify the chamber is empty. An empty chamber isn’t an excuse to goof off with your gun – remember that as far as you’re concerned that thing is loaded even if you can see daylight through the barrel.
  7.   Following the FOUR RULES, we can get into the nuts and bolts of the MK15.

loading/unloading your firearm


  • Insert a loaded magazine and verify it is locked in place
  • Pull the charging handle to the rear and let it go. Really, don’t be clingy.
  • Flip the selector to the ‘SAFE’ position


  • Remove the magazine
  • Lock the bolt to the rear
  • Verify empty chamber


Despite what your father’s uncle’s brother’s former roommate who may have served in Desert Storm once said, AR’s run better when lubricated. Lubricated doesn’t mean oil leaking out and pooling on the ground like your ‘94 Pontiac. We mean applying a few drops of an appropriate lubricant on key friction points. These points will become obvious after a trip to the range – they’re all the shiny spots where the finish begins to wear, and most are on the bolt and carrier. For now we’ll define ‘appropriate lubricant’ as our favorite, Break Free CLP, until someone comes along with an endorsement gig. 

To access the ‘lube points’, pop out the rear lock pin located behind the safety. It pushes out one way, drivers-side to passenger side, unless you’re Chunk from Goonies and can mash it through the wrong way. Make sure the bolt is forward on an empty chamber or else you won’t get very far. 

Once the pin is out, the gun will hinge open like your great-grandaddy’s shotgun. You can now pull the charging handle out half way to remove the bolt carrier group. This is where all the magic happens and if you only keep this one part of your gun cleaned and lubricated, chances are it will run. 

While all your unmentionables are hanging out you may as well wipe down the trigger group and apply a few drops of oil here too. Learn how to disassemble your bolt carrier group (11-year old kids do it on YouTube) and give it some detailed maintenance every so often. Q-tips are your friend.

Put it back together in reverse, lock your bolt to the rear, and let’s talk ammo.


If you have a MK15 marked ‘5.56 NATO’ on the upper receiver it will eat any round marked 5.56 or .223. Even our .223 WYLDE barrels are safe to use 5.56 ammunition. If your cousin Ray-Ray brought some M855A1 back from the Sandbox, don’t shoot it in your MK15 if you value your warranty – that stuff is proof-round hot. 

The .300 Blackout kids can feed their gats supersonic or sub-sonic ammo. Our twist rates (1/7 or 1/8) will stabilize both in normal conditions. Normal means CONUS, not the back range of the Himalayas chasing Taliban insurgents, although the data pool on cartridge performance at those altitudes and temps is growing steadily. 

The chubby subsonic .300’s will hang up in a standard 5.56 PMAG. The solution is to use a metal USGI-style mag or the .300 BLK PMAG.


So, here we are in the middle of some world-class anarchy in the middle of a global pandemic. Some of you may have purchased your MK15 for one or both of these reasons. Some may have intended to head off the senile octagenarianwho thinks no one needs an ‘AR14’. Whatevs. The problem is 4 million of your fellow Americans have come to the same conclusion and have bought all of the guns and ammo in the supply chain. 

While milspec M193 or M855 (NOT M855A1) are the gold standard for 5.56 ammo, good luck finding it at a reasonable price. You may need to substitute. Steel case ammo has coatings that can build up in the chamber and cause stuck cases. Have a solid cleaning rod to deal with stuck cases and clean the chamber more frequently. Not like Ray-Ray preparing for inspection, but hit it after a few hundred rounds.

DON’T USE RELOADS. Just Don’t. We don’t care how long Uncle Bob has been rolling his own, it will void your warranty. Also, sticking anything in your mag that rhymes with ‘Canned Meat’ is a roll of the dice I wouldn’t take with any gun, having personally witnessed three guns blown to scrap from that stuff.

For our customers that are new or casual gun owners, some advice:

Buy a few extra mags – they can wear out, get lost, stepped on, etc. The rule of thumb is 10 per semi-auto rifle, although my Dad had an M1 Carbine with only 2 mags and considered it adequate to defend his 2-room apartment in Queens.

Get a sling – a simple 2-point is more than adequate. Single-points are for SWAT Teams, and the 90’s called and got their 3-Pointers back. A long gun without a sling is like a pistol without a holster. Amateur hour.

Stock up on some ammo when it becomes available. Have at least enough to fill all of your mags and some extra for practice. 

Sights – You can add a set of flip-up or fixed iron sights, or an optic, or both. A quality red-dot is a great choice if shooting from contact distance out to 250, 300 yards.

For greater range and precision on a rifle, one of the 1-4, 1-6, or 1-8 variable optics are the new hotness, especially the illuminated versions. 

Magnified optics on an AR-pistol are frowned upon by ATF as it may constitute a ‘re-design’ intended to be fired from the shoulder, and may land you in SBR hot water. Stick with irons or dots on the pistols. 


Check out the plethora of available knowledge in print and electronic media. I’m not saying you need to memorize The Black Rifle 1 & 2, but the USMC and Army Tech Manuals are available for a few bucks each. Stick with reputable sources – just because Ray-Ray shot a cellphone video of him cleaning his M4 with a brillo pad and a toilet plunger doesn’t mean it’s good advice. Keep checking our Blog page and our social media for updates and the occasional worthwhile bit of info.


Get some as soon as you can. A trained rifleman can do some impressive precision shooting out to the limits of the rifle and it’s cartridge. No matter where you may find yourself, you will never wish you had less training.

A hunter safety course is an awesome start even if you think hunting has no place in modern society.You’d be wrong, but Hunter Safety is a course that teaches you how to safely walk around with a loaded gun. How to transport it, and how to not accidentally shoot someone in the face with it. It is taught everywhere, is endorsed by whichever state teaches it, and is almost free. 

There are the NRA Safety Courses and NRA Personal Defense in the Home. Not a bad start, they are sort of like a Red Cross First Aid class for guns. 

If you want Paramedic-level firearm training you should start perusing the websites of the national shooting schools. The Sig Academy, Gunsite, Rangemaster, Tactical Response, and the Seattle Shooting Academy are just a few of the places out there. 

And speaking of Paramedics, take an emergency trauma class. Not a first aid boo-boo class, but one that leaves you prepared to stabilize a sucking chest wound long enough for the meat wagon to respond. The better shooting schools will offer this as well. 

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