TTAG reader and fellow Marksmanship Training Center member Luke Skywalker (not his real name, but he wanted to tell his friends he made me call him that) had a question on barrel taper and just what it does for a rifle.
“My question is about barrel taper. I see lots of guys talking contour and I’ve been shooting heavy Savage varmint (contour) at 1K for years and I never needed a thicker tube. I have seen lots of the guns in your articles and you’ve got some wild tapers and lengths. Does any certain taper make a difference for long range? How about short range, like 300 yards? Does it really make a difference if I’ve got a pencil or a pry bar out there?”
Master Skywalker is a good long range shooter and uses the Old Republic’s favorite cartridge, the .308 Win. (Yes, I know Luke was not alive in the Old Republic era, and no it’s not nerdy to know that about probably the most popular character in modern cinema…next to his dad.)
I’m a reluctantly-converted 6.5 shooter by necessity, however my old favorite, and the one I will probably end up returning to as my age climbs and nostalgia grows, is the .308 Win. I fondly remember my first 1/4” five-shot group with a .308 and I held on to that round for a very long time…but I digress.
Skywalker’s rifle is a custom job and I really like it. It’s an American Rifle Company Mausingfield action in a Foundation stock (the material here appears to a high-compression and similar to linen micarta) with a 20-inch 1:8 twist barrel, source unknown to me.
It’s a Savage shank, but he declined to tell me where it came from, though I have my suspicions as to its origin. His glass is a US Optics 5-25, though not the same as my own version of that optic as seen in my TTAG articles, which is now called the Foundation series (not related at all to his stock). He’s a hell of a shooter and he really does the .308 Win a service. Something about bulls-eyeing womp rats, or so he tells me.
As such an accomplished shooter, I wonder why it is that he asked me about contour at all. I shoot a variety of contours in my line of work and across my work guns, but I’m not a guru by any stretch.
The major thing that contour addresses is heat. I know this may seem like a dumb answer, but it’s really true. Weight is a factor when it involves the transport of a rifle, but that’s secondary in that you can save weight using a carbon fiber barrel while also having a heavy contour.
Heat dissipation is critical here in that a heavy or thick steel barrel takes longer to get hot and usually cools slightly faster due to a greater surface area, thus letting a shooter have a wider window in which to avoid the negative effects of heat buildup. These negatives are stringing, group migration, and wide/unpredictable groups.
A skinny barrel thus heats up faster, which in turn results in a decrease in accuracy and other aforementioned detriments. When it comes to steel barrels, a light contour saves weight at the sacrifice of consistency from shot to shot, though this is really relative to the shooter and intended end use.
An elk hunter with a featherweight .300 Win Mag may only ever fire one shot a season, and for that reason it’s folly to attempt five-shot groups that take heat buildup into account. The elk hunter is best advised to go to the range and let his barrel cool for as long as possible between not just groups, but individual shots.
The match shooter has heat to worry about if he is shooting benchrest or PRS. These guns fire a number or rounds, often in rapid succession and do well to have barrels that can handle the heat consistently. They are often quite thick, but can end up so thick that they render the rifle hard to move.
My heaviest rifle is 21 lbs. and is a beast to drag around. I like how accurate it is, but I’m not a fan of the weight. I am not going to change it, however, as I already have lighter rifles and it’s not my intent to make all of them the same.
To answer the latter questions posed by Skywalker, I don’t think that there is one specific contour that excels at any given range. A heavier barrel — steel or carbon fiber — will in theory produce better results over a skinny one given equal round count and distance.
Can I say that a Medium Palma is ALWAYS better than an M24 contour? No. Can I concluded that every M24 contour barrel is better than every Savage Varmint? Again, no. A barrel’s contour is really a subjective thing in that shooter’s end use and preference needs to be factored in as well. In a manner of speaking, if it ain’t broke….
When it comes to shorter barrels, the effect of contour is minimized to a degree as a shorter barrel of equal contour to a longer barrel is always stiffer. This is a constant and you’ll see my work rifles, such as the spiral flute 6.5 barrel in this article, are quite thick and short. They deliver impressive accuracy at the cost of a few feet-per-second.
Weight savings isn’t very important on a stationary gun, and where necessary, like on the all-tan stalking rifle, I use carbon fiber for weight savings while having an equally thick contour. The all-tan gun weighs just six pounds where the black-and-tan is 15.5 lbs. They are equally accurate on paper, but the difference in handling is like night and day.
In the end, there isn’t one best contour for any given distance. I think that you’ll see few ‘pencil’ thin barrels in serious, multi-round competitions and 21-pound guns hunting out in the field will be as rare as hen’s teeth.
Short range and long range shooting both benefit from accuracy, and you can get away with less barrel at shorter ranges, though you may still want to have enough barrel to maintain at least a couple follow-ups if things go pear-shaped.