Short-Barreled Precision Rifle Performance Demystified…Again
By Dan Zimmerman on January 28, 2014
Article by Josh Wayner
I’ll preface this by stating that I am not in any way biased in respect to the use and application of traditional length rifle barrels or associated weapons, but my area of study has been mostly in making weapons more compact and useable for real-world scenarios. If anything, I suggest that readers try out my observations for themselves and draw their own conclusions. Since my last article, I’ve received a very large number of questions and stacks of hate mail regarding rifle barrel length from many individuals as well as members of our industry and community . . .
There seems to be a great deal of Freudian angst when barrel length and bullet performance are mentioned in the same sentence. As such, I was confronted by a vast array of conjectures and speculations that were, at best, unsupported and fairly biased. The truth of the matter is, there’s a great deal of difference in what a shorter barrel can yield and what the potential applications are. But maybe because I’m an optimist, I see advantages where others see impotence.
The vast majority of criticisms I received were in regard to the speed of bullets fired out of said short tubes. It appears that a large number of individuals are fixated on the concept of velocity and that bullets must be moving at Mach 11 and call the remaining rounds in the magazine ‘Goose’ and ‘Iceman’ to be taken seriously when in flight. My first and only advice to anyone who drools over ballistic tables is to invest in a subscription to a quality financial periodical, because at least those numbers can get you somewhere when you apply them, and while you’re at it, subscribe every member of congress, too. Velocity is like the vain, fair-haired vixen that your friends are always talking about. You always want to get more of her, but you don’t really know why other than just superficial attraction. The allure of a high velocity number on your ballistic card is just too attractive for most to resist.
Loads and Specifications
In my personal opinion, the .308 Winchester is by far the best candidate for chambering in your short barrel. Other calibers will of course work, but not all do as well as others. The biggest complaint I have against sub-.300 caliber chamberings in shorter barrels is the reduced mass and limited selection of quality heavy bullets that are available currently. This might be a generalization, but unless you have a wildcat chamber, there’s little that the .308 can’t do in a short barrel that some other caliber can best. And believe me, I’ve looked.
No other commonly available cartridge gives you the ability to push a 168gr .30cal bullet out of about 11 inches of rifling at 2380fps while not wasting powder or barrel life. There is a such thing as too short, and anyone looking to run a sub-12” .30 caliber should look seriously at 300 Blackout, as it’s more efficient in regard to powder used and velocity produced. Think a short barreled .300 Blackout is a close range brush popper? Travis Haley sure doesn’t think so, and neither do the targets he rang at 750m.
In point of fact, I don’t think that any rifle of any caliber really ever needs a barrel over 20”. I’m not alone in that sentiment, as many Magpul fans or long range students out there who own The Art of the Precision Rifle will know, cowboy patriot Todd Hodnett states that he will never own another .338 Lapua over 20” again. I can hear it now: “Heresy! Heresy! The big brand makers like Remington and Savage make .338s with 26” barrels plus brake and they must know better!” When those guys yell at you, just smile politely and sleep well knowing that the extra feet per second that they claim won’t save their ballistic souls.
I’ve found that short barreled rifles like my 13.5” .308 do their best with a medium weight bullet travelling at a moderate velocity propelled by a modest charge of medium burning powder. See a trend? The thing with shorter barrels is that you have to be mindful of what components you use to load them. And handload you must to get the best performance. Unless, that is, you count Lapua’s new 170gr FMJ load, which is supposed to be for .308s as short as 12” with a claimed 16” velocity of 2460fps using ‘low-flash’ powder, there isn’t a lot out there that really works well from the factory out there that gives good velocity and low flash signature.
The hands-down best powders for a short .308 are IMR4895 (not H4895, they are different actually), Hodgdon Benchmark, and Hodgdon Varget. Of those, good old IMR4895 provides the lowest flash signature and is the most temperature stable, which is really kind of laughable when you realize that the other two are billed as ‘Extreme’ and are supposed to be consistent across a wide range of temps. To top that off, the Hodgdon website has a graph claiming IMR4895 to be the worst performing powder of those listed. Somebody call Alex Jones, I smell a conspiracy!
Low pressure primers, specifically the CCI 200 Large Rifle variety, work very well for getting good loads without flattening the primers. Really, any number of quality 168gr-class bullets can be used that way, including Hornady, Sierra, Nosler, and Barnes. I personally like the Hornady BTHP, but the AMAX is good too. To push them, I use a charge of 42gr IMR4895 in Lapua brass loaded to 2.835”. This gets me an average 70 degree velocity of 2380fps at the muzzle from my 1:10 twist barrel.
Short Barrels and Bullet Flight
Here’s where people get confused and angry. What I’m about to say may offend some, but it’s the truth: velocity is abstract. I’ll give you a few minutes to think about what kind of things you’re going to write me in the comments section. When you get back, I’ll tell you why it doesn’t matter.
The truth is that every shot is different and entirely dependent on a host of external and internal variables. Virtually every gun rag out there lists five shot averages on their data tables, and for good reason. Velocity is an abstract concept and isn’t concrete. Even if everything is exactly the same down to the powder kernel, there is still some variance in velocity even if it can’t be easily measured. That’s life.
My own .308 Win load isn’t a perfect 2380 fps. That number is an average – I’ve had bullets move as fast as 2390 fps and as slow as 2368 fps in the same batch, and I’m a seasoned precision handloader. Because of that, we get slight variances in point of impact.
Let’s say I’m on the 540 yard line at South Kent Sportsman’s Club, my home range. Off of the elevation setting of five mils at that distance from my 100 yard zero on a 70 degree day, the individual round moving at 2390 will impact in the same place at 5 mils, but the individual bullet moving at 2368 will impact at 5.1 mils. That may not seem like much, but the group just opened up by 2” if you were holding precisely. Now, let’s say those first two shots were already 4” apart. Now you just dropped that last one in low, making your overall group at that range kinda lame.
It wasn’t your fault; velocity is just a vain lady. She gets worse, but the thing that you have to remember is that velocity is nothing more than an estimate that begets another estimate. By averaging 2380 fps, we’re assuming that those shots are typical of the rest of the lot. But that may not be true.
If there were two hotter loads in that bunch, they raise the average and thus create error in the predicted trajectory. See how that can be a problem? Now imagine that you’re sitting behind your .338 and shooting at a distance of 1900 yards and your muzzle velocity estimate is 2900 fps. It’s actually 2839 for this particular cartridge. Yeah, you just made a $7 noise. But don’t worry, it wasn’t your fault. Velocity happens.
Now let’s go out into the snow. It’s 10 degrees and that sucks, and so does your velocity now. My loads drop down to a nice 2300fps average at this temperature, and my 540 yard setting is now 6.3 mils. That’s 1.3 mils on average more drop just from temperature and air density alone from my 70 degree point of impact. So in the extreme temperature range from 100 to 0 degrees, I have about 1.5 mils of variance at 540 yards. The effects of temperature are constant, and velocity is constantly affected by the environment. Do you see now how velocity isn’t something that can be used as a marker of effectiveness or efficiency? It’s constantly changing; therefore, the terminal and external ballistics of the bullet in flight are changing, too.
So, let’s rewind for a minute and put all that velocity talk into context. In my last piece, I noted that there was only a 15% variance between the 26” barrel and the 13.5” both firing the same 168gr handload. 15% isn’t enough to matter to me in the long run. When you fire your long 26” barreled rifle at 2805fps average, that bullet has slowed down to 2380 by the time it hits 200 yards. If you were to fire your 16” barreled rifle at an average 2610fps, you will be hitting 2380fps at only 100 yards.
At a range of 540 yards, the 26” barrel yields 3.5 mils of drop from the same 100 yard zero on a 70 degree day. That’s 30% less drop. When you take the 16” barrel and fire at that range, you’re looking at 4.1 mils of drop, which is only about a 20% difference over the 13.5” length. Let’s drop the temperatures a bit and see what happens. At 10 degrees, our 26” barreled rifle is now impacting at an estimated 4.1 mils. The 16” is now hitting at an average of 4.9 mils. Compare that to the 13.5”, which is at 6.3 mils of estimated drop. In other words, there’s a 17% difference between 26” and 16” and a 24% difference between 16” and 13.5”. On the extreme end, there is a 36% difference between 26” and 13.5”, which really isn’t a big deal. Here’s how it looks in graph form. Notice anything interesting?
I thought you did. You can see that temperature alone can play havoc and make your 26” drop like your 16”, which is now dropping like your 13.5”. Abstract indeed. Temperature plays a huge role in how bullets fly, as does elevation and wind. So let’s close the distance a bit to a range most people can shoot at regularly without much environmental interference, like 300 yards.
So what? That still looks unimpressive? That’s like a million clicks of difference, Right? On a 70 degree day, there is only a 6.4” (2.1 MOA) difference in point of impact between the 13.5” and 26” barrels. On a 10 degree day, the difference is only 10.8” (3.6 MOA). That equates to very little real-world difference. If you happen to run a 16”, the differences are even less noticeable, those being 4.3” (1.4 MOA) at 70 degrees and 7.5” (2.5 MOA) at 10 degrees. None of this is really that big of a deal for real-world applications.
What? How is that not a big deal? Let me tell you: all bullets drop, that’s a fact of life. Modern high quality optics can account for it as simply as clicking the elevation turret or looking through the Horus reticule. Laser rangefinders can give you an accurate range estimate with which you can use to predict a flight path using a quality ballistic calculator. Some like the JBM Ballistics version are available free online and even can allow you to extrapolate a solution for any distance across any range of temperatures on a single data card. Range, click, bang. It’s that easy these days whether you are firing a 13.5” .308 at 1260 yards or a 30”.300 Win Mag at 368 yards.
“But Josh! What about wind?” Well, what about it? Just like talking to girls, reading the wind is tricky and can result in embarrassment if not done properly. I’m not going to detail wind or spin drift much, but I will say that you need to pay careful attention to both. A typical .308 will have as much as .2 mils of spin drift at 600 yards naturally in a no-wind environment. As far as wind is concerned, she is a cruel, cruel bitch that will break your heart as soon as make eyes at you. Reading the wind is a challenge for every shooter, as there isn’t a very reliable gauge to measure wind at every point along a given bullet’s path, just like there isn’t one to gauge a woman’s opinion of you during a conversation. Time, patience, and missed shots are part of the learning curve no matter what barrel length or velocity you shoot with when it comes to wind.
That is another reason I encourage proficiency at medium distances, as there’s significantly less wind influence at closer ranges. This might be a given, but it’s a good given in that there is very little significant difference in drift between a 300gr .338 Lapua at 2800fps (.4 mil drift) and a 168gr .308 at 2380fps (.8 mil drift) at 300 yards in a 10mph 90 degree left to right wind. Even though it is twice as much, it’s only a difference of 4.4” (1.4 MOA). The thing is the .308 gets there at less than 1/5 the cost, less than half the powder, and with a weapon shorter than the Lapua’s barrel when folded. If we’re talking semi-auto, the cost of the system alone can dictate choice, not to mention the availability of parts and weight penalties. That extra 1.4 MOA just got a bit pricy, in other words.
Applications of the Short Barreled Precision Rifle
So what does all this velocity and drop stuff matter, longer barrels are clearly superior on the graphs, right? Well, not really. Let’s take a look at typical engagement scenarios from three perspectives: police, military, and civilian. According to the American Sniper Association (ASA) literature I’ve got on hand, the average distance for a police sniper to fire at (not necessarily hit. Looking at you, NYPD…) his target was only 51 yards based on a 2005 report summing up over 200 sniper shots. That’s hardly far at all, but well within the realistic expectations of urban combat. At 50 yards, there is literally no disadvantage to having a short barrel. In the military, a shorter barrel isn’t something that’s new. The SCAR 17 with a 13” barrel is in use with the SEALs currently, and is no doubt the primary target of Lapua’s new 170gr offering. A shorter barreled weapon is also far easier to conceal and jump with, bonus if it has a folding stock as well.
The civilian market has had a hard time grasping the benefits of a shorter weapon. For one, Americans are literally obsessed with the whole 1000+ yard thing. I seriously doubt that most people who own a .338 Lapua east of the Mississippi has had a chance to fire it past 900 yards enough to become truly
proficient. Besides private land and a few public ranges, there isn’t a great deal of support for extreme ranges compared to normal 3-400 yard setups. The only 1000 yard range that I can access within a couple hours driving is the Marksmanship Training Center (MTU) in Lake City, Michigan, and even then I have to be a member to get in, so I try to get on private land instead, which isn’t the safest thing to do sometimes. The most complete list of ranges over 500 yards I could find consists of only around 270 ranges across the whole country, which seems like a lot until you realize that there are over 25,000 ranges in operation according to public records available from NIOSH. That means that roughly 1% of ranges will allow you to get the most out of your long barrel. Why own a gun you can never get the full potential out of? Owning a .338 Lapua and firing it only at a 200 yard covered range on a bench is like going 30mph in your Lamborghini to pick up groceries. You’re better than that unless you’re Bruce Wayne, in which case you already have a Gatling gun that can fire fingerprint bullets into bricks or some shit in addition to your 4th Amendment-violating sonar goggles.
I’m not going to get into the reasons why people buy the guns they do, but I will say that in America, if it can’t be done by a .308Win, it really shouldn’t be done at all. I’m not trolling here, I’m just pointing out the facts, and don’t play the bear card on me, either. If you feel comfortable carrying a hot loaded .357 or .44 mag up north, realize that a 168gr .308Win, even a 13.5” one, has more force at 1/3 mile than a hot 240gr .44 does point blank. And to think, Fred Bear would have been horrified to learn that the polar bear he shot with an arrow back in 1966 could have laughed off a .308 according to some of the experts I received mail from recently. In short, a short barrel isn’t a handicap for hunting. It’s just the contrary. Encore pistols have been using short barrels in rifle calibers for years, but slap a bolt action and a stock on, and it suddenly becomes a CQB mall ninja’s toy found only in the hands of a Die hard villian. How is that right, Hans?
My hunting rifle is one of my Scally Hill Systems Mk4Mod7 systems that uses a 13.5” barrel. When folded, it’s just 26.6” long and can maneuver through brush like it’s not even there. Even with the stock in position, it’s only 35.75” overall with a 13” length of pull. It’s smaller than most AR15s out there, uses AICS mags, and it’s still a .5 MOA gun after 4000+ rounds and counting out to 540 yards, and yes, that’s an average of .5 MOA. For hunting anything in America, that’s hard to beat when size and accuracy are concerned. Not to mention, it’s the ideal sized rifle for a guerrilla sniper or armed civilian marksman in a time of unrest.
For most realistic uses, a short barreled rifle isn’t a handicap. Considering that most hunting and shooting is done at around 100-300 yards given terrain, available practice areas, and shot ethics, there isn’t really a disadvantage to speak of. Yes, there is more wind drift and drop at extended distance, but a weapon needs to be fitted to its environment. If 540 yards is the maximum distance at which I practice regularly, it makes sense that I build a weapon that reaches its potential at that distance since I can regularly train with it at that range and not using an excessive amount of resources to get there. In my mind, carrying a 50” long .338 Ultra Magnum after deer knowing that the shot is going to be around 100-300 yards is akin to carrying a Custom Shop full size .500S&W Magnum as an EDC piece. Bigger bullets do not make up for poor marksmanship, nor does more velocity. Don’t sell yourself short by investing in a shoulder-bruising powder-hog that you can’t afford to practice with at any real distance in the hopes that you will be like Chris Kyle because Chris had a big gun and shot bad guys. Firstly, you
won’t ever be Chris Kyle and secondly, don’t get your hopes up about shooting bad guys. Go buy Modern Warfare 3 and learn to quickscope with the MSR. Trust me, it’s cheaper and you’ll only get bruised verbally by 12 year olds. Get something that you can fire comfortably, effectively, economically, and lethally at the maximum distance that you can fire at regularly. My bet is that you won’t need a 26” .338 Lapua or even a 20” .308 to do that. In other words, don’t try to make up for your shortcomings with more power. That will only magnify them.
So there you have it. Short barreled systems work and they fit what most people will need a rifle for. Can you go longer? Sure, you can. But the real question is why you would want to, knowing that you will probably never wring the full potential out of a short barrel to begin with at your typical range or hunting excursion. That being said, you’re the master of your own decisions, and fitting your weapon to your environment or preferences is ultimately your task. Personally, I’m a minimalist utilitarian in the true sense, and my practicality dictates that I keep going smaller and smaller until I reach the most compact, useful balance between size and power. Cars, guns, girls, all the same: the smaller, smarter, and more capable the better
Thanks to John for the Article, what say you? Long or short barreled rifles a good idea?
Mark is the Chief trainer at TTGC and T3. With over 8 years in the security industry as a US Marine, Professional Instructor and constant student, Mark has a passion for assisting others with Training and Equipment. We hope to hear from you here on the T3 blog and look forward to some good conversations.