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August 13th, 2021

Advanced Barrel Weight Calculator — Compare Lengths, Contours

Online Pac-Nor Barrel Calculator

pac-nor barrel weight contour calculatorCan you guess what your next barrel will weigh? In many competition disciplines, “making weight” is a serious concern when putting together a new match rifle. A Light Varmint short-range Benchrest rifle cannot exceed 10.5 pounds including scope. An F-TR rifle is limited to 18 pounds, 2 oz. (8.25 kg) with bipod.

One of the heaviest items on most rifles is the barrel. If your barrel comes in much heavier than expected, it can boost the overall weight of the gun significantly. Then you may have to resort to cutting the barrel, or worse yet, re-barreling, to make weight for your class. In some cases, you can remove material from the stock to save weight, but if that’s not practical, the barrel will need to go on a diet. (As a last resort, you can try fitting a lighter scope.)

Is there a reliable way to predict, in advance, how much a finished barrel will weigh? The answer is “yes”. PAC-NOR Barreling of Brookings, Oregon has created a handy, web-based Barrel Weight Calculator. Just log on to Pac-Nor’s website and the calculator is free to use. Pac-Nor’s Barrel Weight Calculator is pretty sophisticated, with separate data fields for Shank Diameter, Barrel Length, Bore Diameter — even length and number of flutes. Punch in your numbers, and the Barrel Weight Calculator then automatically generates the weight for 16 different “standard” contours.

pac-nor barrel weight contour calculator

Calculator Handles Custom Contours
What about custom contours? Well the Pac-Nor Barrel Weight Calculator can handle those as well. The program allows input of eight different dimensional measurements taken along the barrel’s finished length, from breech to muzzle. You can use this “custom contour” feature when calculating the weight of another manufacturer’s barrel that doesn’t match any of Pac-Nor’s “standard” contours.

Caution: Same-Name Contours from Different Makers May Not be Exactly the Same
One key thing to remember when using the Barrel Weight Calculator is that not all “standard” contours are exactly the same, as sold by different barrel-makers. A Medium Palma contour from Pac-Nor may be slightly different dimensionally from a Krieger Medium Palma barrel. When using the Pac-Nor Barrel Weight Calculator to find the weight of a barrel from a different manufacturer, we recommend you get the exact dimensions from your barrel-maker. If these are different that Pac-Nor’s default dimensions, use the “custom contour” calculator fields to enter the true dimensions for your brand of barrel.

Smart Advice — Give Yourself Some Leeway
While Pac-Nor’s Barrel Weight Calculator is very precise (because barrel steel is quite uniform by volume), you will see some small variances in finished weight based on the final chambering process. The length of the threaded section (tenon) will vary from one action type to another. In addition, the size and shape of the chamber can make a difference in barrel weight, even with two barrels of the same nominal caliber. Even the type of crown can make a slight difference in overall weight. This means that the barrel your smith puts on your gun may end up slightly heavier or lighter than the Pac-Nor calculation. That’s not a fault of the program — it’s simply because the program isn’t set up to account for chamber volume or tenon length.

What does this mean? In practical terms — you should give yourself some “wiggle room” in your planned rifle build. Unless you’re able to shave weight from your stock, do NOT spec your gun at one or two ounces under max based on the Pac-Nor calculator output. That said, the Pac-Nor Barrel Weight Calculator is still a very helpful, important tool. When laying out the specs for a rifle in any weight-restricted class, you should always “run the numbers” through a weight calculator such as the one provided by Pac-Nor. This can avoid costly and frustrating problems down the road.

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August 13th, 2021

Compact, Lightweight Field Rigs — Howa Mini Action Rifles

Howa Mini Action Rifle 6.5 Guys Legacy Sports 6.5 Grendel 7.62x39

We’ve been fans of the Howa Mini Action rifles since they were introduced a few years ago. With actions that are nearly an inch shorter than typical “short actions”, these Mini Action rigs work great as a compact “truck gun” or carry-around varminter. Current chamberings are: .223 Rem, 6.5 Grendel, 7.62x39mm, and .350 Legend. There are 20″ heavy contour and 22″ standard contour barrel options, plus a 16.25″ heavy for the .350 Legend only.

6.5 Guy Ed Mobley Tests the 7.62×39 Howa Mini Action Rifle
Howa Mini Action Rifle 6.5 Guys Legacy Sports 6.5 Grendel 7.62x39

The Howa Mini Action rifles come with the excellent HACT 2-stage trigger and a 5-round or 10-round, synthetic detachable box mag (depending on caliber). The Mini Action’s bolt is 13% shorter than on regular short actions, providing a shorter, faster bolt throw. Weight is also reduced. This makes for a nice, compact (and very shootable) package.

6.5 Guys Test Howa Mini Actions in 6.5 Grendel and 7.62×39

The 6.5 Guys recently secured a pair of Howa Mini Actions, one chambered in 6.5 Grendel and the other in 7.62×39 Russian: “After trying out the Howa Mini Action rifles at SHOT Show 2017, we got a couple of loaners in 6.5 Grendel and 7.62×39 courtesy of Legacy Sports. These rifles are known for their smooth cycling and lightweight actions, as well as some unique chamberings for bolt rifles (6.5 Grendel, 7.62×39). Long story short, we really enjoyed them.” In fact Steve liked his 6.5 Grendel enough that he plans to purchase the gun. Get the full scoop in this VIDEO REVIEW:

The folks at Legacy Sports also conducted extensive accuracy tests of commercial ammunition in 6.5 Grendel and 7.62×39. The most accurate 6.5 Grendel ammo, with a stunning 0.29″ group, was Alexander Arms with Lapua 123gr Scenar; second best (0.56″ group) was Hornady with 123gr A-Max bullet. The most accurate 7.62×39 ammo was Hornady 123gr SST with a 0.62″ group in the 20″ Heavy Barrel version. View Howa’s Test Reports with these links:

6.5 Grendel Factory Ammo Data | 7.62×39mm Factory Ammo Data

Howa Mini Action Rifle 6.5 Guys Legacy Sports 6.5 Grendel 7.62x39
Click HERE for full-screen image.

Legacy Sports Video compares Mini Action Rifles in .223 Rem and 6.5 Grendel:

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