20110416 Over
the last several months there seems to have been a resurgence in
interest in the 14.5” barrel with permanently attached muzzle device to
bring the barrel length out to 16”. Let’s take a look at the pros and
cons of this setup as it seems that some who consider it are unaware of
some of the issues that come with them.First, a background. Federal law requires that any rifle with a barrel length less than 16” be registered as a short barrel rifle, or SBR. This involves either incorporating, forming a trust, or getting “chief law enforcement officer” (the sheriff or chief of police in your area) to sign off, filling out some paperwork, paying a $200 tax to the feds, and waiting for them to get around to approving it which can often take 3-4+ months. I have over-simplified the process, but there it is. Contrast this with having a 16” barrel which you can simply buy and attach to your rifle. The typical muzzle devices attached to AR barrels add anywhere from 1”-2” of length to the barrel, and therefore the OAL of the rifle. The BATFE has ruled that a permanently attached muzzle device counts as barrel length, and therefore the shortest possible package you can have without registering an SBR would be a barrel less than 16” with a device of your choosing attached to make it 16” overall. The most common method of attaching the device is to drill a hole through the device and partway into the barrel, inserting a “blind” pin (meaning it can only be driven in, not out) and covering up the exposed end with a weld before grinding and polishing it down to match the profile of the barrel and refinishing. Removal of the device requires it to be destroyed, and oftentimes the home shadetree gunsmith winds up destroying the barrel in the process as well. In a world f $100, $150, $400+ muzzle devices this is no small matter to remove it. The primary benefit of this configuration is pretty obvious: shorter overall length. If a 16” barrel plus 2” long muzzle device becomes an 18” barrel, going with a shorter barrel and permanently attaching the device will save you 2”. Whether or not this 2” really matters is a subject of debate, but proponents often cite moving around building interiors, getting in and out of cars, etc. as viable reasons for wanting to save 2”. In addition to the saved length, obviously, comes saved weight. Depending on barrel profile, the weight savings in going from a 16” barrel to a 14.5” barrel is approximately 3 oz. While this may seem insignificant, and it may even be insignificant depending on your use, consider that his savings is at the end of the barrel which is a lever, amplifying the perceived weight, and slowing down the ability to swing the muzzle of the gun from target to target. Neither of these benefits matter if you’re only ever going to sit at the bench at the static range and plink. It may matter to you, from an aesthetic standpoint, if the primary function of rifle is to post pictures of your rifle on the internet. A less obvious benefit may be a “whole greater than the sum of the parts” thing. Several retailers and manufacturers have been combining 14.5” barrels, mid-length gas systems (meaning the gas tube is 2” longer than the standard, carbine-length gas tube from the M4 system), and various compensator or brake-style muzzle devices, along with gas port sizes tuned to the system, to produce some very soft-shooting guns. No, the 5.56x45mm round does not have a lot of recoil, but it does have some. The issue here, however, is not recoil but muzzle climb. As the muzzle climbs the sights come off the target. If the next shot is taken before the sights are back on target, there is a cumulative effect and the muzzle continues to climb. This is what happens in full auto when you see the muzzle continue to rise as long as the trigger is held to the rear. In order to achieve good accuracy the shooter must get the sights back down on target before breaking the next shot. This takes time. Therefore if you can decrease the amount of muzzle climb you can decrease the time it takes to fire subsequent shots. Some people argue that the difference between a 16” mid-length gas system with compensator X is not measurably slower than a 14.5” barrel with mid-length gas system with the same compensator. And they may be right. Certainly there are very few shooters who may need that minuscule fraction of a second and even fewer that can wring that kind of potential out of the gun. And again, so-called “split times” (the time between shots, measured with a shot timer) is totally inconsequential when shooting groups from a bench. There are potential downsides to this system. Shorter OAL and potentially shorter split times sound like great benefits, but there are trade-offs in everything in life. In this case they are primarily due to that pinning and welding of the device described earlier. Recall, also, that removal of this device means destroying the device at best and potentially destroying the barrel at worst if the person doing the work is not careful and experienced. In any event, it is not as easy as simply unscrewing the device and screwing on another one, and exceeds the tools and ability of most gunowners. And there is the cost of sacrificing the device. What many new gunowners who are considering this system fail to understand is that removal of the muzzle device is the first step toward replacing many handguard systems. Free-float rail systems vary, but the more common are one-piece extrusions with dedicated barrel nuts that replace the stock part. It is the dedicated barrel nut that becomes the issue. In order to get the barrel nut off the front sight base, or gas block, must be removed. In order to remove the front sight base, or gas block, the muzzle device must be removed. Therein lies the problem. This may or may not present a problem. If you are perfectly happy with the muzzle device you have, and the handguard system you have, removal of either may not present a problem for you. And there are some handguard systems, even free-float systems, that do not require the removal of the front sight base, and therefore do not require the removal of the muzzle device. Some require the removal of the delta ring but that can be carefully cut off and removed and is a much less expensive part to destroy than the muzzle device. But even with these systems, your choices will be limited. And if your gun or upper starts out with one of the free-float rail systems that has a dedicated barrel nut and/or is made from a one-piece extrusion, you may be stuck with the parts that are on the gun unless you want to destroy the muzzle device. and if you’re happy with the setup you have, none of this is an issue. The question becomes, if you are new to the AR, how do you know what you want? Or if your needs or applications change later on, how will you adjust to the changes? We are living in the golden age of the AR system, with new and improved parts, pieces, accessories, and configurations coming out every month, sometimes every week. Even for the most competent of shooters, technology changes and needs and desires change, and being locked into a given configuration or system may limit that shooter’s ability to change with the times. What is considered the cutting edge handguard system, or muzzle device, today may not be tomorrow. Case in point, last year I took delivery of a 14.5” barrel, mid-length gas system upper with free float rail system that extends over the gas block, and a muzzle device pinned in place. Not a month after taking delivery, a newer, potentially better, muzzle device hit the market. It promised equal reduction in muzzle climb combined with less visible flash and less side-blast (a persistent trade-off with muzzle brakes). Had this 14.5” upper been a purchase instead of a T&E loaner, it would have required significant cost to change to this new device. Then, not 6 months later, the company making the free-float rail system redesigned it to mount to the stock barrel nut instead of the proprietary one on my sample, and incorporated a flip-up front iron sight into the design as well. If the old mounting system is phased on in production, even my ability to change the tube out for different lengths will be severely limited. There are certainly benefits to the 14.5” barrel with pinned muzzle device. Decreased overall length, saving on $200 tax-stamps to the government, reduced weight, and potentially even reduced split times in dynamic shooting scenarios. But there ain’t no free lunch, and these systems do come with some trade-offs as well. While nothing is un-doable, the ability to make changes at home for the average gunowner is greatly reduced, and no matter the ability there are added costs due to the sacrificial nature of removing the device. If the gunowner has to seek professional assistance with the removal and re-pinning the costs are magnified. Given that the benefits are really only appreciable by the smallest percentage of shooters, it is best to choose a 16” barrel length, with a muzzle device that is easily removed and replaced at home, if you are considering your first, or only, AR pattern carbine. |
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CONCEPTS >
The 14.5" AR Carbine Barrel |