HOW THE AR15 OPERATES AND WHAT THAT MEANS FOR RECOIL CONTROL

by Josh Mazzola of AR15Targets

Often people ask, "how can I better control the recoil of my AR15?"  Answers to this question will vary from source to source, as will emphasis on different techniques and alterations to stance and grip, but today, I'm here to tell you that simply changing the placement of the weapon's stock, can radically change the controllability of your carbine, specifically when that carbine is an AR.  To better understand why we need to pay attention to stock placement, we first need to understand how the AR platform mechanically functions.  

When the shooter pulls the trigger, the firing pin strikes the primer, igniting the powder, and sending the bullet down the barrel. A large amount of the hot gas which is propelling the bullet follows it out the muzzle of the weapon (the expansion of which causes recoil), but some exits through the barrel's gas port and travels back down through the gas tube into the receiver.  Here, the gas is injected into the bolt carrier group (BCG) and propels it backwards into the buffer and spring.  The spring compresses and the the bolt carrier group travels partially into the buffer tube (the movement of which causes recoil).  After the spring has reached full compression (under general circumstances) it then drives the buffer and bolt carrier group forward where the BCG is able to pick up and chamber a new round.  The important part of this sequence to take note of for the purposes of recoil control as it relates to stock placement, is the cyclic movement of the bolt carrier group.  It's important to note that in the AR15, the bore as well as "recoiling system" are in a straight line which ends in the top of the buttstock.  What this means is that as the weapon is fired and subsequently cycles, the energy of the bullet leaving the muzzle as well as that of the bolt carrier group reciprocating inside the gun, is directly transferred through the top of the stock.  

Red line signifying the "path" of energy 

Note how I have the stock slightly lower with my shoulders wrapped around it
so that the mass of my torso can absorb the energy coming off the weapon.
The picture is frozen as the weapon is at its peak of the recoiling sequence,
yet the muzzle has barely deviated.

So what this means for shooters is that getting the mass of our bodies behind the top of the stock will drastically mitigate the felt recoil of the weapon.  To do this, we need to move the stock from the traditional location, where the top of the stock sits above our shoulder/body mass, down so that the top of the stock actually sits in front of our musculature rather than just air.  It also helps to move the stock inward towards the body's center-line as much as is comfortable in order to mitigate horizontal deviation of the muzzle during recoil; this requires some squaring of the shoulders toward the target (more than some are used to).  It's also important to note that by squaring the shoulders we are then able to wrap them over and around the stock which will further aid in dealing with the recoil energy.  This technique is used to some degree by almost all of the shooters who are competitive in the action shooting sports as well as those who teach/use a carbine for practical applications in real world environments.  It is extremely effective in aiding the shooter in keeping the gun flat and on target for faster more accurate follow-up shots.  It is however, only a piece of proper carbine grip and stance that is required for the highest level of recoil control.