Iron Sights and Optics

Now a days there are many different types of iron sights for your AR 15 rifle but for this paper we will focus on two, the A1 and A2 sights. The A1 type’s rear sight only supports windage (right-left) adjustments, and the A2’s rear sight has both windage and elevation adjustments. Because it is less complex, the A1 sight system is more rugged and less likely to be knocked out of zero but in theory has less granularity in adjustments.

To set mechanical zero run the rear sight in one direction, left or right, until it stops. Count the number of clicks in one direction, then again going the other direction until it stops. Divide by two. Then count that number of clicks in toward center. Record this. For the A2 turn the elevation knob to the 8/3 position and then 1 more click clockwise. Adjust the front sight until it is level with the sight post. You are now at mechanical zero.

Fire groups of three shots at the zero target from a distance of 25 yards. Find the center of your groupings and measure from there to the central vertical and horizontal lines in order to determine how far you need to adjust the sights. Lines on zero targets are in 1” increments from the center of the bullseye. To move your groupings to the left, turn the windage knob on the rear sight to the left and to the right to move your grouping to the right on the target. Looking from the top of the sight, the front sight post will need to be turned clockwise to raise groupings and counter-clockwise to lower them as they appear on the target. Repeat until you can consistently hit center mass.

Now that your Iron sights are at setup, let’s briefly discuss how to choose a scopes. First you need to decide what you want the scope for, Home defense, plinking, competition, or long range? With those questions in mind, consider the below:

 

1. A more expensive scope is usually made better.

2. A larger objective lens, the glass facing your target, can gather more light.

3. A larger scope allows more light transmission and usually enables more adjustments.

4. There’s really no reason to buy a scope that can outrange the ammo you’re shooting.

5. Lower magnification means wider field of view, which means it’s easier to acquire your target and keep on top of the situation around it.

Red dots can enhance you scope or be used alone. When used alone they allow you to remain focused on the target with both eyes opened. These sights allow you to point and shoot by placing the “dot” on the target and pulling the trigger. Red dot sights offer maximum available light transmission and wide fields of view. They are considered the fastest sights for target acquisition and also offer unlimited eye relief.

Let’s talk about the most common mount for your red dot and / or scope, Picatinny rails. The Picatinny rails are military standard MIL-STD-1913 (AR), which was adopted on February 3, 1995. They are the most common rails on modern AR-15 rifles. The recoil grooves are consistently spaced allowing manufactures to provide consistent and secure mounting hardware.

REFS:

https://info.stagarms.com/blog/bid/378263/Zeroing-the-Iron-Sights-on-Your-AR-15-Rifle

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

AR-15 Barrel Extensions Retention

Correct barrel installation is very important. An incorrectly installed barrel can cause serious injury or death. We are going to discuss the correct way to get your barrel installed. First thing we need to do is gather up some tools and supplies:

Armorers wrench, torque wrench, punch, gas tube alignment rod, receiver clamp and / or padded vise, and grease. A grease like AeroShell 33MS or MCARBO designed for aircraft and graphite free is what you will need. Without the proper grease, your upper and barrel could eventually suffer from galvanic corrosion, galling, crack and come loose.

1. Grease the barrel extension prior to installing into the receiver.

2. Align the index pin with the recess in the upper receiver.

3. Push the barrel and upper together so the index pin fits in the slot. It is OK to use a rubber mallet to install the barrel to the upper if things are too tight.

4. Apply grease to the threads of the upper receiver and hand tighten the barrel nut assembly on to the upper.

5. With your torque wrench and armorers tool tighten and loosen the nut 3 times to seat the threads. Use the torque wrench to tighten only! Use your armors wrench to loosen. The goal is to align the space between the teeth at 12 o’clock.

6. Torque from a minimum of 30 ft lbs to a maximum of 80 ft lbs. Your goal is to align a gap between the teeth to 12 o clock of the upper to permit the gas tube to slide through. Once torqued, the gap in the delta ring, weld spring, and C clamp will need to be positioned to 12 o’clock as well.

a.) If it won’t line up, the easiest, and safest method is to order a barrel nut shim. If you are going to be doing several of these, might be worth having a few on hand. These are thin shims that will be installed in the barrel nut to help align the next gap / tooth. Follow the instructions included with the kit and it should fix any alignment issues.

7. Slide the gas tube into the upper receiver.

8. Push the front of the gas tube into the front sight / gas block base. There will be two holes on the end that goes to the sight post / gas block, one hole for the gas, another for the roll pin. Align the holes and use a punch to install the roll pin.

9. Drop on your hand guards and you are done.

REFS:

https://youtu.be/ey3cIB5u7q4

https://youtu.be/h_tELLisZMw

http://www.thenewrifleman.com/ar15-barrel-installation-guide/

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

AR-15 Magazine Checks

Magazines work by using a spring to push a fresh round up in front of a bolt or slide. That cartridge is then pushed into the chamber either manually or by a compressed spring. The magazine under the bolt is exerting varying upward pressure on it and that those varying amounts of pressure change the downrange POI. Magazines have varying pressures, single stack magazines have a straight up, lighter pressure while double stack magazines will have a higher pressure as well as applying pressure from either side depending on round placement. Other factors in the magazine that can influence the bolt carrier group are springs, feed lips, and followers.

There are several ways to try and work with this. When competitive shooting never use you magazine as a rest. This will apply excessive and inconsistent pressure on the bolt. Lots of NRA sponsored events don’t allow this anyway, train as you compete. Use a reliable lead sled or rest. Try to use the same one if possible, if you cannot, sand bags or you range bag will work as long as the magazine is off the ground. Clean and maintain you magazines as shown below.

These instructions are for the military style metal, G.I. issue mags. The principal is the same for all magazines:

1.) Pry the tab at the rear of the magazine down so that the detents can clear the spine.

2.) Grab the tab with your needle nose pliers and pull the tab, sliding the floor plate from the bottom. Be careful the tab is under spring tension.

3.) Remove the spring and follower from the bottom of the magazine body.

4.) With the spring and follower out, wipe down the inside of the magazine by pulling a clean microfiber cloth through the hollow tube of the magazine body a couple of times.

5.) Wipe down the spring and follower to remove any remaining dust and sand. Depending on your environment, apply a light coat of lube if desired.

6.) Ensure that there are no dents and everything is in the shape it is supposed to be.

Save any serviceable parts and reassembly in the opposite order. 5 → 1

Match the magazine to the firearm. This can be accomplished by labeling your magazines. There are all kinds of ways to do this. Simplest is to use a white marker and a method that you can use to match the magazine to the weapon. Some manufactures have “dimples” on the magazine you can color in a pattern to label them

Using the above tips should help you improve your POI.

REFS:
U.S. Army TM 9-1005-319-10

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

AR-15 Tools, Maintenance and Repair

As either a hobbyist or professional there are some basic tools you will need to build and maintain your AR 15 rifle. You don’t need to start off with the most expensive tools out there, several of my first tools came from Harbor Freight, and it is what I could afford at the time. As you move on and figure out what you use most, you can get some better tools in needed. Sometimes you need to make do with what you have, be careful not to scratch or damage the weapon you are working on. Here is a basic list:

Ball-peen hammer
Nylon/brass hammer
Screwdrivers:
Flat Tip
Phillips
Hex
Torx
Needle-nose pliers
Bench mat, I have been using $5 yoga mats from 5 and below.
Bench vise
Padded vise jaws
Set of roll pin holders and punches in numbers 1, 2, 3, & 4
Barrel nut tool or combination armorer’s wrench
Buttstock tool (collapsible stock only)

I will call this Basic advanced. I know people will disagree, but if you are only going to do one or two rifles you can get the job done without them;

Lower receiver vise block
Upper receiver vise block set
Universal bench block
Handguard removal tool

The course material does a great job listing the more specific tools required to build your AR 15:

Barrel-Specific Tools:

Torque wrench (½” drive, 30 ft./lb. to 150ft./lb.)
Taper starter punch (3/32”)
Flat punch (⅛” to peen the swivel rivet)
Staking punch
Sight adjustment tool (specific to your type of sight, A1 or A2)
Gas tube alignment pin
Snap ring pliers
Breaker bar
Strap wrench

Upper Receiver Specific Tools:

Headspace gauge set – Field, Go, and No-Go
Rear sight elevation spring tool (for assembling the A2 sight)
Sight adjustment tool (for your type of sight)
Ejector removal tool

Lower Receiver Specific Tools:

.151 diameter punch (for locating trigger parts & installation)
Pivot pin detent installation tool
Bolt catch pin punch
AR-15 hammer trigger jig
Hammer trigger drop block (for adjusting the hammer & trigger)

Using the basic set of tools listed above will help you clean your rifle. First thing you need to do is to clear the weapon, ensure the bolt carrier group is forward and the safety is on. Push the front and rear take down pins out and separate the upper from the lower receiver. Then disassemble the upper receiver pull the charging handle back and remove the bolt carrier group. The charging handle will drop down as you continue to pull and can be removed from the receiver. On the left rear side of the bolt carrier, you’ll see what looks like a cotter pin, this is the firing-pin retaining pin. Pull the pin straight out and the firing pin will drop out of the bolt. Turn and remove the cam pin the bolt will now slide out. Make sure the gas ring gaps are not lined up and are in good shape. Next remove the extractor pin, the extractor will then come out. Inspect the extractor assembly spring and rubber piece to ensure good working order. Clean everything up with a small cleaning brush and solvent then wipe down with CLP. Re-assemble the bolt by putting the extractor and spring assembly back in the bolt and inserting the extractor pin, return the bolt to the carrier and insert the cam pin and rotate, insert the firing pin and the retaining pin. Run a couple swabs with solvent followed by CLP down the barrel. Insert the bolt group and charging handle to the upper receiver

After putting it all back together you should do a functions check:

1. Place the selector switch on fire and squeeze and hold down the trigger. You should hear the hammer striking the firing pin.
2. While still holding the trigger, pull the charging handle fully to the rear and let go to reset the hammer.
3. Release the trigger. You should hear a mechanical click. This is the disconnector releasing the hammer onto the trigger.
4. Place the selector switch on safe and try to pull the trigger. The hammer should not fall. If it does there is a problem with your selector switch and/or trigger.
Now that we have described the tools needed to build and maintain their AR-15-style rifle, listed instructions for cleaning your rifle and talked about the functions check. Let’s talk about various ways to store your rifle. Locked up and out of the wrong hands is the preferred way to store your firearms. Locking gun cabinets start at around $100 and can go as high as you wallet will allow. You can get wall to wall carpet, lights, and dehumidifiers. My thought on this is play big or stay home, I only want to make this purchase once so go as big as I can. I also want to protect my investments, firearms, from fire and theft. A locking gun cabinet might not do the job but a good quality safe can handle upwards of 1400 degrees Fahrenheit and any crow bar a thief can throw at it. You can safeguard your other valuables as well, not just your firearms.

REF:
U.S. Army TM 9-1005-319-10

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

Maintenance and Troubleshooting of AR-15 Type Rifles

Field Stripping can be done with what everyone should have out in the field, a bullet. Might not be the best tool, but in a pinch it will do everything you need to do. First thing you need to do is to remove the magazine, clear the weapon, ensure the bolt carrier group is forward and the safety is on. Set the firearm so the barrel is pointer to the right. Push the rear take down pin towards you, it will not come all the way out and you should feel the upper and lower separate when it is pushed far enough. Now do the same for the front take down pin. You can now separate the upper from the lower receiver.

To disassemble the upper receiver pull the charging handle back and remove the bolt carrier group. The charging handle will drop down as you continue to pull and can be removed from the receiver. On the left rear side of the bolt carrier, you’ll see what looks like a cotter pin, this is the firing-pin retaining pin. Pull the pin straight out and the firing pin will drop out of the bolt. Turn and remove the cam pin the bolt will now slide out. Make sure the gas ring gaps are not lined up and are in good shape. Next remove the extractor pin, the extractor will then come out. Inspect the extractor assembly spring and rubber piece to ensure good working order. Clean everything up with a small cleaning brush and solvent then wipe down with CLP. Re-assemble the bolt by putting the extractor and spring assembly back in the bolt and inserting the extractor pin, return the bolt to the carrier and insert the cam pin and rotate, insert the firing pin and the retaining pin. Run a couple swabs with solvent followed by CLP down the barrel. Insert the bolt group and charging handle to the upper receiver.

The lower assemble contains the trigger group, buffer system and the stock. To remove the buffer and spring, push in on the buffer and depress the retainer pin. The buffer and spring will come out. Clean the buffer assembly, spring, and tube with a swab dampened with CLP. The trigger assembly will require some grease at the pivot points. Inspect the stock for cracks and other damage.

The AR-15-style firearm is a versatile, modular, and easy to maintain rifle that with a little maintenance will last you a very long time.

REF:

U.S. Army TM 9-1005-319-10

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather

Steel Targets

There is a lot of talk about steel targets. You can go on line and find enough information to boggle your mind. I decided to go with ¼ inch AR400 steel gongs. These are for my personal use, nothing more. I will post pictures after I light them up.

Here is shot of the 4×8 sheet.

AR400 Steel for targets

I had to remember how to use my plasma cutter. It was not pretty, but I got it done:

With my Army back, I found it very hard to work on the floor so broke down the plate into smaller lighter sections. With help we put it up on some saw horses to make it easier to cut.

I also discovered these little gems from Swag Off Road. I put the screw and washer in one of the unused holes to create an adjustable stand off. I just adjust for the locations and tighten down the 2 nuts to keep my cutting tip off the steel.

And the bottom. Ignore the scoring:

Greatly improved my cuts:

Here is a shot of the targets for this run:

1 – 20 inch

1 – 12 inch

5 – 8 inch

4 – 6 inch

Drilled 2 holes in each, painted and setup:

Facebooktwittergoogle_plusredditpinterestlinkedinmailby feather