Pretty much all AR15 pistol uppers are paired with threaded barrels. This expands their functionality and makes it a lot easier to add muzzle devices, two of the most popular of which are suppressors and muzzle brakes, which are sometimes called compensators.
This post will break down the advantages and disadvantages of each one with specific respect to how they will perform when attached to an AR15 pistol. Here are a few things to know.
Why Suppress?
Suppressors, also called silencers or cans, are muzzle devices that have internal baffles or vanes that either trap or redirect gasses, or both.
The main effect of a suppressor is that it will substantially cut back on the muzzle pop of the AR15 pistol. Since these are very loud and produce a lot of muzzle pop, this makes suppressors great muzzle devices.
Add in the fact that they can protect your hearing as well as the hearing of others near you at the range and you have another benefit.
Another advantage of suppressors is that they increase chamber pressures, which corresponds to greater muzzle velocity. This can be a thing that AR15 pistols really struggle with, since they have short barrels. That means suppressors increase performance in this way, too.
What doesn’t get talked about enough is that, since suppressors trap and redirect gasses at the muzzle, they can also cut back - significantly - on felt recoil, sometimes by as much as 50%. This is a huge advantage of suppressing an AR15 pistol.
On top of that, since they trap gasses at the muzzle, they can help cut back on, even entirely eliminate muzzle flash, helping to keep your sight picture clear and unobstructed.
Why Not?
Despite the glaring advantages of these muzzle devices, there are some potential issues of outfitting an AR15 pistol upper with a suppressor.
One is that they are NFA items, which means you will need a separate tax stamp and background check for each one you purchase.
Suppressors also add length and weight to the AR15 pistol upper, which is something you might want to avoid. Part of the draw of an AR15 pistol is that it is compact; you lose some of that advantage with a suppressor.
Suppressors are also very hard on the gun’s action, especially if your AR15 pistol upper has a gas action instead of a blowback action. They will wear out the BCG’s gas rings a lot sooner.
Silencers also run really dirty. They will need to be cleaned more frequently and will blast a lot of fouling back into the bore, chamber, and action that will also need to be cleaned out.
With that said, there are plenty of advantages to offset these drawbacks. So what about muzzle brakes?
Why a Muzzle Brake?
Whereas a suppressor is supposed to make an AR15 pistol quieter, a muzzle brake will actually make the gun a lot louder. Muzzle brakes are designed to redirect gasses at the muzzle so as to push the muzzle down, helping to cut back on felt recoil.
Like suppressors, muzzle brakes can cut back on felt recoil by 50% or more, which is a welcome upgrade since AR-15 pistols kick harder than their full size counterparts.
Because they cut back on felt recoil so effectively, they help shooters keep their sights trained on target, enabling faster, more accurate follow up shots.
Also, and unlike suppressors, muzzle brakes are not NFA items, which means it is a lot easier to buy one.
Because muzzle brakes only redirect gasses - they don’t trap them - they won’t cause much of a difference in chamber pressure, and so they won’t be as hard on your gun’s gas system and action.
Why Not?
Like a suppressor, a muzzle brake will add length and weight to an AR15 pistol upper, which might be something you want to avoid.
In addition, a muzzle brake will make an AR15 pistol much louder. This will not be attractive to many shooters, since the muzzle pop of an AR pistol is already ridiculously loud.
Some muzzle brakes that port gasses upward will make the muzzle flash a lot more dramatic and concentrate it over the front of the muzzle, obstructing the sight picture - another disadvantage.
Other than these, there aren’t too many serious disadvantages to adding a muzzle brake to your AR15 pistol upper’s barrel.
Which Is Right for Your AR15 Pistol Upper?
Ultimately, whether a muzzle brake or a suppressor is right for you will depend on your intended use of the platform.
However, since a suppressor will offer most if not all of the advantages of a muzzle brake while also cutting back on muzzle pop, that’s probably the best of the two.
Still, the choice is yours. Take a look through our collection of AR15 pistol uppers and muzzle devices and if you have questions about parts or compatibility get in touch with us at Sales@MCSGearup.com.