During my career in the military I was fortunate enough to use a wide variety of optics on the M-4 weapon system. While all of these generally performed well, each was built with a specific purpose and I routinely saw optics being mounted and employed incorrectly, and improper optic use quickly became a personal pet-peeve. Consequently, I’ve put together a list of considerations, tips, and TTPs (tactics, techniques, and procedures) to help you decide what kind of optic to place on your AR, and some things to keep in mind while you are training.
Purpose is paramount when deciding what type of optic to use, and most AR15 optics can be grouped into these two categories:
For the purposes of this article I will give a quick rundown of the background, purpose, and correct employment of each optic, followed by a few tips, training TTPs (tactics, techniques, and procedures), and lessons learned from my experiences with these optics.
I have noticed several questions on the forum recently focused on lubrication and maintenance of the carbine. So, I thought I’d post some generalized guidelines for maintenance, cleaning and lubrication. If followed, these guidelines will keep your carbine functioning optimally with minimum time expenditure.
The AR15/M4/M16 family of firearms has gotten a poor reputation due to the bad experiences and poor information provided to operators in the past. This weapon platform is highly reliable when maintained properly. Some general guidelines to follow to insure reliable function and life time service from your firearm:
1. Attempt to field strip and quick clean your carbine after each shooting session. Even if this only means you have time to de-grease the bolt carrier, bolt face and clean out the chamber and bore. This will go a long way toward maintaining reliability.
2. Soak small parts such as the charging handle, bolt carrier, bolt and its small parts in a Tupperware container of Hoppe’s #9 overnight. This will make cleaning these small, hard to reach surfaces much easier and save you time and trouble in the long run.
3. Attempt to fully field strip, inspect and thoroughly clean your firearm after every 3000 rounds. Note “witness marks” or where metal has rubbed on metal wearing away finish. These are important lubrications points. Look closely at the gas key on top of bolt carrier and make sure it is still tight.
4. Keep a close eye on components that are critical to the proper operation of your carbine such as the extractor and spring, ejector and spring, gas rings, firing pin and buffer spring. It is a good idea to have back ups for all of these essential parts in a range bag or kept at home.
5. Inspect the extractor claw making sure there are no cracks where the metal is thin or chips and that the claw is not filled with carbon or debris.
6. When lubricating remember that “less is more”. Your bolt and carrier do not have to be soaking wet. Extra lubricant will attract dust, dirt and debris when firing your carbine. A light coat or sheen is all that is needed.
7. Make sure the charging handle is not bent. Lateral stress is put on the charging handle during aggressive cycling and over time they will bend and the finish will wear on one side creating witness marks.
8. Utilize a q-tip, tooth pick or dental pick to clean carbon or chunks of debris out from around the trigger group. Visually verify the legs of the trigger spring are the same length and not broken.
9. During dedicated field stripping remove the action spring/buffer spring from the receiver extension and inspect. Remove the buffer from the spring and degrease along with spring. Lightly lubricate the spring before replacing buffer and spring into receiver extension.
10. Learn and understand the “Cycle of Operation” for your carbine: Feeding, Locking, Firing, Unlocking, Extracting, Ejecting, Cocking, Chambering. Understanding this cycle will aid in recognizing and diagnosing any malfunctions or problems experienced while firing your carbine.
Recommended Cleaning Tools, Solvents & Lubricants
Listed in the order I use them. No fancy cleaning tools are necessary to maintain a carbine. Field expeidient items found at any small mini-mart or box store can be utilized for 99% of carbine maintenance. However, good cleaning kits such as those manufactured by Otis are a good investment and can make the job easier. http://www.otisgun.com/
There are numerous degreasers and lubricants available on the market today ranging in price. Over the years I have tested/used pretty much all of them. The best degreaser I have found is Mil-Comms MC25. http://www.mil-comm.com/. For lubricants I now use and recommend Mobile One motor oil found at any box store, if these motor oils work in high performance vehicles and motorcycles they will certainly work in my carbine. A single container of Mobile One ($2.oo) will last several years. Use sparingly, apply a very small amount to the tip of a finger and then apply to common lubrication points.
About Chris Fry
Chris is the owner and director of training and curriculum development for Modern Defensive Training Systems in Utica, NY where he conducts courses in reality driven practical combatives skills, extreme close quarters physical defense, tactical folding knife and edged weapon combatives and combative pistol, carbine and shotgun skills. Chris has been an active instructor with Progressive F.O.R.C.E. Concepts in Nevada since 2003, servicing law enforcement, military and select government agencies. Chris is a certified AR15/M4/M16 and Glock armorer, contributor to various online firearms resource websites and a frequent presenter at national and international personal protection and small arms training conferences for both citizens and law enforcement.
For more information or to locate carbine, shotgun or pistol training in your area see: http://www.mdtstraining.com
Many people, who ask me about building their own AR-15, always seem unsure about which barrel twist to get for their rifles. Hopefully this mini article will help you guys figure out what is best for your needs.
In general, rifling twist rate determines the optimum weight of the bullet for a given caliber. It also determines the speed of the bullet by preventing any yaw or pitching. Rifling twist is measured in the number of revolutions per inch of barrel. For instance a 1 in 9″ twist means that the bullet made one revolution while traveling 9″ down the barrel.
So, what is the best twist rate? Well the answer nobody wanted is, “It Depends!” 🙂 A good rule of thumb is that the more weight or longer the bullet is, the faster the twist rate has to be in order to stabilize the bullet. Also, in general, lighter/shorter bullets can usually be fired in barrels with faster twist rates, but heavier/longer bullets cannot be fired in barrels where the twist rate will be too slow. Let’s examine this in more deatail as it relates to AR-15’s.
The original M-16 started off with a 1 in 14″ twist rate which is good enough for bullets around 55gr. However, when temperatures dipped below freezing, the density of the air caused the bullets to lose their spin, resulting in much less accuracy. In order to solve this problem, the military adopted a twist rate of 1 in 12″. The SS109/M855, which is 62gr, required a 1 in 10″ rate to stabilize, but the military settled on a 1 in 7″ rate due to the need to fire the heavy and long tracer rounds.
What does this mean for the civilian AR-15 enthusiast? Well, considering most barrel manufacturers produce their barrels in both 1 in 9″ and 1 in 7″, choosing either will not hurt the performance of the rifle for the majority of shooters out there. If you think you will be shooting the heavier grain bullets or tracer rounds, then it is probably safer to pick a 1 in 7″ twist rate barrel.
I hope that this short article on AR-15 barrel twist rates helped clear up some information! Please feel free to leave us some comments or questions if you would like more information!