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February 4th, 2020
The 2020 Berger Southwest Nationals kicks off 2/5/2020 at the Ben Avery Range outside Phoenix, AZ. The big event starts with a 600-yard Mid-Range Match. Many of the nation’s most talented F-Class and sling shooters will be there. But no matter what your skill level, it is still possible to make major mistakes that can spoil the day and/or put you out of the running for the entire match. This article aims to help competitors avoid the big errors/oversights/failures, aka “train wrecks”, that can ruin a match.
Photo by Sherri Jo Gallagher.
In any shooting competition, you must try to avoid major screw-ups that can ruin your day (or your match). In this article, past F-TR National Mid-Range and Long Range Champion Bryan Litz talks about “Train Wrecks”, i.e. those big disasters (such as equipment failures) that can ruin a whole match. Bryan illustrates the types of “train wrecks” that commonly befall competitors, and he explains how to avoid these “unmitigated disasters”.
Urban Dictionary “Train Wreck” Definition: “A total @#$&! disaster … the kind that makes you want to shake your head.”
 Train Wrecks (and How to Avoid Them)
by Bryan Litz of Applied Ballistics LLC
Success in long range competition depends on many things. Those who aspire to be competitive are usually detail-oriented, and focused on all the small things that might give them an edge. Unfortunately it’s common for shooters lose sight of the big picture — missing the forest for the trees, so to speak.
Consistency is one of the universal principles of successful shooting. The tournament champion is the shooter with the highest average performance over several days, often times not winning a single match. While you can win tournaments without an isolated stellar performance, you cannot win tournaments if you have a single train wreck performance. And this is why it’s important for the detail-oriented shooter to keep an eye out for potential “big picture” problems that can derail the train of success!
Train wrecks can be defined differently by shooters of various skill levels and categories. Anything from problems causing a miss, to problems causing a 3/4-MOA shift in wind zero can manifest as a train wreck, depending on the kind of shooting you’re doing.
Below is a list of common Shooting Match Train Wrecks, and suggestions for avoiding them.
1. Cross-Firing. The fastest and most common way to destroy your score (and any hopes of winning a tournament) is to cross-fire. The cure is obviously basic awareness of your target number on each shot, but you can stack the odds in your favor if you’re smart. For sling shooters, establish your Natural Point of Aim (NPA) and monitor that it doesn’t shift during your course of fire. If you’re doing this right, you’ll always come back on your target naturally, without deliberately checking each time. You should be doing this anyway, but avoiding cross-fires is another incentive for monitoring this important fundamental. In F-Class shooting, pay attention to how the rifle recoils, and where the crosshairs settle. If the crosshairs always settle to the right, either make an adjustment to your bipod, hold, or simply make sure to move back each shot. Also consider your scope. Running super high magnification can leave the number board out of the scope’s field view. That can really increase the risk of cross-firing.
2. Equipment Failure. There are a wide variety of equipment failures you may encounter at a match, from loose sight fasteners, to broken bipods, to high-round-count barrels that that suddenly “go south” (just to mention a few possibilities). Mechanical components can and do fail. The best policy is to put some thought into what the critical failure points are, monitor wear of these parts, and have spares ready. This is where an ounce of prevention can prevent a ton of train wreck. On this note, if you like running hot loads, consider whether that extra 20 fps is worth blowing up a bullet (10 points), sticking a bolt (DNF), or worse yet, causing injury to yourself or someone nearby.
3. Scoring/Pit Malfunction. Although not related to your shooting technique, doing things to insure you get at least fair treatment from your scorer and pit puller is a good idea. Try to meet the others on your target so they can associate a face with the shooter for whom they’re pulling. If you learn your scorer is a Democrat, it’s probably best not to tell Obama jokes before you go for record. If your pit puller is elderly, it may be unwise to shoot very rapidly and risk a shot being missed (by the pit worker), or having to call for a mark. Slowing down a second or two between shots might prevent a 5-minute delay and possibly an undeserved miss.
Photo by Sherri Jo Gallagher.
 4. Wind Issues. Tricky winds derail many trains. A lot can be written about wind strategies, but here’s a simple tip about how to take the edge off a worse case scenario. You don’t have to start blazing away on the command of “Commence fire”. If the wind is blowing like a bastard when your time starts, just wait! You’re allotted 30 minutes to fire your string in long range slow fire. With average pit service, it might take you 10 minutes if you hustle, less in F-Class. Point being, you have about three times longer than you need. So let everyone else shoot through the storm and look for a window (or windows) of time which are not so adverse. Of course this is a risk, conditions might get worse if you wait. This is where judgment comes in. Just know you have options for managing time and keep an eye on the clock. Saving rounds in a slow fire match is a costly and embarrassing train wreck.
5. Mind Your Physical Health. While traveling for shooting matches, most shooters break their normal patterns of diet, sleep, alcohol consumption, etc. These disruptions to the norm can have detrimental effects on your body and your ability to shoot and even think clearly. If you’re used to an indoor job and eating salads in air-conditioned break rooms and you travel to a week-long rifle match which keeps you on your feet all day in 90-degree heat and high humidity, while eating greasy restaurant food, drinking beer and getting little sleep, then you might as well plan on daily train wrecks. If the match is four hours away, rather than leaving at 3:00 am and drinking five cups of coffee on the morning drive, arrive the night before and get a good night’s sleep.”
Keep focused on the important stuff. You never want to lose sight of the big picture. Keep the important, common sense things in mind as well as the minutia of meplat trimming, weighing powder to the kernel, and cleaning your barrel ’til it’s squeaky clean. Remember, all the little enhancements can’t make up for one big train wreck!
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February 4th, 2020
Forum members are lamenting that they can’t find Hodgdon H4350 at local gunstores or through major online Vendors. There ARE a few shops that do have H4350 (and Varget) on the shelves. But the nearest H4350 may be in another state, far away. Therefore, you may want to consider using Alliant Reloder 16 (RL16). We highly recommend Reloder 16 for shooters who can’t find H4350. RL16 has a very similar burn rate, excellent accuracy, and is VERY temp stable. Some ace F-Class shooters (among Top 10 at Nationals) tell us that, with hot ambient temps (80-100+° F), RL16 is even more temp stable than H4350.
| Powder Availability at Online Vendors — H4350, Reloder 16, Varget |
| Vendor |
Hodgdon H4350 |
Alliant Reloder 16 |
Hodgdon Varget |
| Brownells |
Out of Stock |
In Stock $207.99 8 lbs. |
Out of Stock |
| Bruno Shooters Supply |
Out of Stock |
In Stock $28.50 1 lb. |
Out of Stock |
| Midsouth Shooters |
Out of Stock |
In Stock $221.31 8 lbs. |
Out of Stock |
| Sportsman’s Warehouse |
In store $229.99 8 lb.* |
In store $31.99 1 lb.* |
In store $229.99 8 lb.* |
| Powder Valley |
Out of Stock |
In Stock $26.05 1 lb. |
Out of Stock |
| Precision Reloading |
Out of Stock |
In Stock $26.67 1 lb. |
Out of Stock |
*This is available in-store only at a few locations. You need to search store locations near you for availability. For example, H4350 8-pounders are available in a couple locations including Show Low, AZ and Midvale, UT. Varget 8-pounders are available in AZ, NM, and WY and a couple other states.
Do You Like H4350? Then You Should Try Reloder 16 — It Is Accurate and Temp Stable
Alliant Reloder 16 is used now by many top shooters for cartridges that work well with Hodgdon H4350. In fact, we’d say that Reloder 16 is the best substitute for H4350 on the market. Alliant’s RL 16 is very temp stable, offers good velocity, and the accuracy is top tier. Some guys report slightly better accuracy than H4350 in the .284 Win, .260 Rem, 6.5 Creedmoor, 6mm Creedmoor, and 6XC cartridges. If you currently use H4350, you should definitely give Alliant Reloder 16 a try. The powder also boasts excellent lot-to-lot consistency and contains a proprietary de-coppering additive.
 This is NOT just a slower version of Alliant’s double-based Reloder 15 (which words great in the 6mmBR and Dasher cartridges). Reloder 16 is a completely new formulation, produced in Sweden by Bofors for Alliant. Reloder 16 utilizes TZ technology, which manipulates the response of the propellant and resists the natural tendency to generate more pressure at higher temperatures and less pressure at lower temperatures. As a result, Alliant’s Reloder 16 offers truly outstanding temperature stability.
Reloder 16 Load Recipes »
Reloder 16 Load Data PDF »
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February 3rd, 2020
At the request of our readers, we provide select “Deals of the Week”. Every Sunday afternoon or Monday morning we offer our Best Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, optics, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
1. MidwayUSA Padded Shooting Mat, $74.99 on Sale
This padded MidwayUSA mat is much more comfortable than typical shooting mats. With 1.5″-thick high-density foam, this is way better for knees and elbows than typical roll-up mats. For your home range, this is a good choice. On sale now for $74.99, this thick mat folds into three sections. It stows flat and fits nicely in the back of a truck or SUV. Actual owner comments: “If you like to be COMFORTABLE … I can highly recommend it! Easy on the elbows. Easy on the knees. Easy on the belly. You can even kneel on it comfortably, even when the surface is rock-hard!”; “I tell you what … Do yourself a favor and spend the few extra dollars on this unit. Highly recommended.” MORE REVIEWS HERE.
2. EuroOptic — Leica 8×42 Geovid LRF Binoculars, $1150 Off
If you’re looking for outstanding glass plus great rangefinding capabilities, the Leica Geovids are among the best you can buy — at any price. Right now save over $1000 on the Leica 8×42 HD-B 3000 Geovids at EuroOptic. These are being marked down to $1799.00 because Leica has introduced a new “smart” Geovid 3200.com model that communicates with a Ballistic App. That new 8×42 Geovid 3200.com starts at $2949.00, so you can save big bucks by buying the previous model. Last year’s 10×42 Geovid is also on sale now for $2499.00.
3. Natchez — ChargeMaster Lite Powder Dispenser, $209.99
Precise powder dispensing is critical for accurate loads. Among the many electronic scale/dispensers on the market, RCBS’s ChargeMaster Lite is a very good choice. This week Natchez is selling the ChargeMaster Lite for only $209.99. That’s a great price — almost $60 cheaper than Amazon. Note: Natchez also offers $5 Shipping with $99+ orders through 2/4/2020 with Code FR200201.
4. Multiple Vendors — 20% Rebate on Federal and Speer Bullets
Now through the end of April, if you purchase at least $100 worth of Federal and/or Speer bullets you can get 20% of the purchase price back. Minimum purchase is $100.00. Maximum rebate of $100 per person or household. Note: The Rebate amount will be calculated on the product purchase price only — that does NOT include taxes and/or shipping/handling fees. This Federal/Speer Rebate is valid for purchases made 02/01/2020 through 04/30/2020. View REBATE FORM.
5. Midsouth — Frankford Arsenal Rotary Tumbler Lite, $99.99
Lots of people love wet-tumbling their brass in stainless pins but not everyone want to do it in a giant unit. We found a sweet deal on the Frankford Arsenal Rotary Tumbler Lite. Midsouth has this unit on sale for $99.99. This tumbler is small enough to fit on a counter but still big enough to hold 300 pieces of .223 Rem brass. For folks on a limited budget who want to start wet tumbling, this is a solid choice.
6. CDNN — Ruger American .30-06 Hunting Rifle, $319.99
Even with so many new cartridge types, the venerable .30-06 Springfield remains a trusted and effective hunting round. Moreover, you can find good .30-06 hunting ammo at most any sporting goods store. Whether you’re looking for an affordable hunting rifle or perhaps a first rifle for a family member, check out this .30-06 Ruger American Rifle with Wolf Camo finish. CDNN’s current sale price is just $319.99 — a great bargain. One recent comparison test declared the Ruger American the best entry-level hunting rifle, and Ruger offers a rock-solid warranty.
7. Sportsman’s Guide — Buck Mark Camper UFX Pistol, $299.99
The Browning Buck Mark is a classic, and for good reason. These pistols are reliable, well-balanced, have a good trigger, and they are very accurate. And now you can get one for under $300.00. Sportsman’s Guide has the Browning Buck Mark Camper UFX with 5.5″ Barrel on sale for $299.99 ($284.99 member price). This Buckmark Camper UFX is a excellent value, especially for Club members who pay just $284.99.
8. MidwayUSA Dogtown Ammo, $21.25 for 50 rounds
Dogtown Ammo, made with Nosler tipped FB bullets, offers great “bang for the buck” for .223 Rem shooters, particularly high-volume varminters. Right now get 50 rounds for just $21.24 (43¢/rd). Or order 200 rounds for $86.99 (42¢/rd). Forum member NDAE15MAN states: “This stuff shoots in all of my .223 Rem guns — 7/8″ to 1″ at 100 yards. Best kept secret for ammo. Shoot exact same groups as Black Hills.” NOTE: MidwayUSA also sells .204 Ruger Dogtown Ammo with 32gr tipped flat-base bullets.
9. Midsouth Shooters — 17 HMR V-Max 500 Round Brick, $89.99
Here’s a great deal for varmint shooters with 17 HMR rifles. Midsouth has the Hornady 17 HMR brick of 500 for a low price of $89.99. That works out to just 18 cents per round — cheap enough that you can blast sage rats all days long and never worry about running out of ammo.
10. Amazon — Two Pairs Safety Eyewear, Cords, Covers, $13.50
Eye protection is important! All you need is one case separation or blown primer to cause serious eye injury. Don’t take that risk. Plus the CMP has made Eye Protection mandatory for all CMP Pistol and Centerfire Rifle events. Here’s a great kit with TWO Sets of safety eyewear, each with a neck strap and carry bag. These feature ANSI Z87.1-rated lenses that are anti-fog and scratch-resistant. The lenses also block harmful UV rays. Get the full SuperLite and SuperClear Lens Technology Kit for just $13.50.
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February 3rd, 2020
With the Berger Southwest Nationals (SWN) taking place this week in Phoenix, we are reprising this discussing of rear bag designs and fill levels. By “tuning” your rear bag you can reduce hop on shot-firing and help your rifle track better. All that can translate to better scores, particularly with large-caliber rifles.
Tuning Your Rear Sand Bags
Over the years, noted gunsmith and a Benchrest Hall-of-Fame inductee Thomas ‘Speedy’ Gonzalez has learned a few things about “tuning” rear sandbags for best performance. On his Facebook page, Speedy recently discussed how sand bag fill levels (hard vs. soft) can affect accuracy. Speedy says you don’t want to have both your front and rear sandbags filled up ultra-hard. One or the other bag needs to have some “give” to provide a shock-absorbing function (and prevent stock jump). And you want to tune your fill arrangements to match your shooting style. Free recoil shooters may need a different fill levels than bag squeezers (who a softer bag but harder ears).
SAND BAGS & HOW TO FILL THEM by Speedy Gonzalez
I was asked several times by competitors at the S.O.A. Matches and F-Class Nationals as to how I fill my sand bags for benchrest competition. Here is a copy of a reply I gave several years ago:
 Back in the old days, Pat McMillan told me: “You can not have two bags filled so hard that you gun bounces on them in the process of firing round at your target, especially if you have a rig with a very flexible stock. The bags must be set up in a manner for them to absorb the initial shock of the firing pin moving forward and igniting the primer.
Then [they must] maintain their shape and absorb the second shock wave as well the rearward thrust and torque of the rifle. What happens to the rifle when this is not done? Well let me tell you. The rifles have a very bad tendency to jump and roll in the bags. This causes many of those wild, lost shots that one can’t explain.”
Here’s some Good General Advice for Bag Set-up:
1. You should not have TWO hard bags [i.e. both front AND rear] in your set-up.
2. Heavy sand magnifies these phenomena.
3. If you are a bag squeezer, pack ears hard and leave bag pliable enough to squeeze for the movement required. You may pack front bag as hard as rules permit.
4. Free recoil shooters pack both bags firm, but not so hard as to allow stock jump. Especially if you have a stock with a very flexible forearm.
5. We use play-ground sand, also know as silica sand. I sift mine to get any large impurities out then mix it with 25% to 50% with Harts parakeet gravel to the desired hardness that I am looking for. The bird gravel keeps the sand from packing itself into that solid as a brick state.
Speaking of bricks — another thing that happens when shooters employ that heavy zircon sand is the ears form a low spot under them from recoil and then tend to rock back and forth with the rifle causing many low shots to crop up. Edgewood makes an Edgewood/Speedy rear bag specially reinforced under the ears to eliminate this scenario.
General Thoughts about Bag Construction and Ear Materials
I do not like the solid double-stitched leather bottoms. While this seems like a good idea, I see more shooters have problems because of them. They tend to slide around the bench and or slide with the rifle on recoil. The standard Protektor with Cordura rabbit ears and an Otto ring bag with a Cordura front would be what I would suggest to the new shooter or one of the Edgewood / Speedy rear bags, these mimic the “Donut” and feature a ring of leather around the bottom circumference that keep the bottom from rocking on the bench or ground[.]
One last note –If you use the Cordura bags, keep them sprayed with a good silicon spray or “Rain-Ex”. This keeps them from getting sticky. — Speedy
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February 2nd, 2020
With the Berger Southwest Nationals commencing this week, we thought our readers would appreciate a showcase of two impressive, state-of-the-art F-Open match rifles. The first, show above, is the .284 RAHM (40° .284 Win Imp) with which Brian Bowling captured the 2019 F-Class Open Division Long Range National Championship. The second rifle belongs to barrel-maker Bryan Blake. Like Bowling’s rifle, Blake’s rig features a low-profile Cerus stock, but with purple highlights. Both rifles have 6-groove, cut-rifled barrels from Blake Barrel & Rifle and both sport Nightforce scopes.
Twin World-Class F-Open Rifles
Report from Bryan Blake of Blake Barrel & Rifle
We had been producing gun barrels for about 1.5 years prior to the 2019 NRA Long Range F-Class Nationals. Brian Bowling started shooting our 7mm barrels in May of 2019. Bowling and I are both on the Rutland team, Team Cerus, which has seven members. Bowling and I received the first Cerus XL stocks from Cerus Rifleworks in August of 2018. The stock was a very straight design.
With our barrels, these F-Open rigs can shoot! In 2018, Brian Bowling and I had the only two clean scores for the first match at the 1000-yard team NRA Nationals. In spring of 2019, I worked with Will of Cerus Rifleworks to see if we could come up with a lower center of gravity design to enhance what was already the straightest stock out there. We developed the Cerus XR stock which features stepped metal rails on the fore-end. I cut my XL Cerus stock and designed the rail system attached to the sides of the fore-end. Bowling’s stock (with black rails) was the second XR in the shooting world. On his very first weekend match at 600 yards he shot a 200-20X with the new XR stock and Blake 7mm 1:8.5″-twist barrel. He was using Berger 184gr 7mm bullets.
In 2019, at the NRA F-Class Long-Range Nationals, Brian Bowling won the F-Open National Championsship with a strong performance. He finished with a ton of Xs, three points ahead of the second place competitor. Before Brian’s impressive victory, we were told by many top shooters that a 6-groove barrel has never won any F-Class Mational event, and hypothetically never would. Well with Brian Bowling’s excellent shooting and reloading capabilities, we achieved a feat many said couldn’t be done.
Bowling’s Championship-winning rifle features a Bat Model B action in the Cerus XR stock. His Blake barrel is chambered for the .284 RAHM wildcat cartridge. This is a 40-degree (40°) version of the .284 Winchester. The .284 RAHM has a straighter case body compared to the original .284 Win.
We built Bowling’s rifle, doing everything except the final clear finish. We can do that work, but were short on time for the Nationals last year. We are proud of the chambering work we do and the quality of our bedding jobs.
Bryan Blake’s F-Open Rifle — the Purple XR
The Purple XR-stocked gun I shoot was built in August of 2019, right before the 2019 NRA F-Class Nationals. The natural wood is complimented by highlights finished with a bright purple metallic epoxy resin that Will from Cerus dreamed up. For this rifle we mated a BAT 3LL action with Blake barrels (switch-barrel configuration). Up front the fore-end rails are painted purple “plum crazy” to match the purple resin. The purple XR is finished with automotive “high solids” clear-coat, and block-sanded for a smooth, flawless look.
Blake’s Rifle is a Switch Barrel — 7mm and .30 Caliber
This Purple XR was set up to be a switch barrel rig, with both a 7mm BBM and a .30 BBM*. These BBM wildcats are based on shortened and straightened .300 WSM with a 40-degree shoulder. On my purple XR rifle as well as Bowling’s rifle, we employ Nightforce optics and load Berger bullets. These are the only glass and projectiles we use in our rifles.
The Purple XR is extremely accurate. Check out this 2.6″ group, shot at 1000 yards during a club match at the Ben Avery Range in Arizona. Yes, that is 1/4-MOA at 1K! Many folks would be very happy with that group at 600 yards. At 1000 yards it is remarkable. No, the rifle can’t do that every time. But this does demonstrate that the Purple XR is a tack-driver. CLICK HERE to see a 3.9 inch, 15-shot group at 1000 yards on the F-Class target (150-15X).
About Blake Barrel and Rifle — History and Barrel-Making Process
Blake Barrel and Rifle was re-launched in 2018. The business was actually started by my grandfather, Robert Blake, in 1966. In 1969 my grandfather stopped doing gunsmithing and making single-point cut-rifled barrels. He transitioned to doing industrial work, and less work for the public. After all those years he and my father, Dave Blake, kept the barrel-making equipment in storage. They kept the gun-drilling machines in the shop as they used them to drill long, deep holes in anything from aircraft parts to electric motor rotors.
In 2012 we got the diamond single-point, sine-bar rifling machine out of storage, along with the Pratt and Whitney double-spindle reaming machine. We then completely rebuilt and updated the equipment. We modified the gun-drill to be a counter-rotating drilling system. What that means is the drill spins at about 20% of the rotational speed, and the barrel at 80%. The counter-rotation keeps the drill on the center axis of the barrel more precisely than just rotating the barrel, or just rotating the drill. We are able to consistently drill holes in our barrel steel (primarily 416R) that at the end of a 33.25″ blank that is only .005″ off of center axis.
We then ream the barrels to be .0004″ below desired finish bore size. After the reaming process we mandrel-hone the bores to be .0001″ below finish bore size. This process eliminates reamer marks in the barrel bore. Therefore very minimal lapping is needed after rifling to remove any tooling marks. We then rifle the barrel to any twist rate we like. With a fine lap after rifling, the barrel has no tooling marks and all surface metal is flowing in the direction of the twist of the rifling.
* 7mm BBM stands for “Blake Bramley Magnum”. Dan Bramley and I developed that cartridge together in October of 2017. The .30 BBM is the “Blake Barrel Magnum”, which I developed in May of 2018.
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February 2nd, 2020
This Technical Report Comes from the Vihtavuori website.
Powder Moisture Content — Did You Know?
Variations in moisture content change the burning rate of a powder and thereby chamber pressures and muzzle velocity. The moisture content of the Vihtavuori N100 and N300 series powders is usually around 1%, while the N500-series’ normal moisture content is 0.6% because of the added nitroglycerine.
So what difference does moisture content make? Here’s an example. In a test, a [Vihtavuori] powder sample was dried by heating it, losing about 0.5 % of its weight. Cartridges were then loaded with the dried powder and fired using a pressure gun. Chamber pressures and muzzle velocities produced by these special cartridges were compared to those produced by cartridges loaded with untreated powder. (The powder charge and bullet were of course the same in both sets of cartridges.)
After Powder Drying:
Pressure Increased 11% from 320 MPa to 355 MPa
Velocity Increased 2.6% from 2526 to 2592 FPS
Comparing results showed chamber pressures increased from 320 MPa to 355 MPa with the dried powder, and the muzzle velocity increased accordingly from 770 m/s to 790 m/s (2526 to 2592 FPS). And note, this is only one example, of one caliber and loading. The difference might be much higher depending on the cartridge and loading combinations.
Recommendation: Store powder below 68°F in 55-65% humidity.
What does this tell us? Well, it seems we need to forget the old saying “Keep your powder dry”! Instead, focus on proper powder storage, at a temperature below 20°C/68°F and humidity between 55 and 65%. Safe reloading everybody!
Tech Tip sourced by EdLongrange. We welcome reader submissions.
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February 2nd, 2020
Erik Dahlberg illustration courtesy FireArmsID.com.
 Sometimes you’ll get a barrel that doesn’t stabilize bullets the way you’d anticipate, based on the stated (or presumed) twist rate. A barrel might have 1:10″ stamped on the side but it is, in truth, a 1:10.5″ twist or even a 1:9.5″. Cut-rifled barrels, such as Kriegers and Bartleins, normally hold very true to the specified twist rate. With buttoned barrels, due to the nature of the rifling process, there’s a greater chance of a small variation in twist rate. And yes, factory barrels can be slightly out of spec as well.
After buying a new barrel, you should determine the true twist rate BEFORE you start load development. You don’t want to invest in a large supply of expensive bullets only to find that that won’t stabilize because your “8 twist” barrel is really a 1:8.5″. Sinclair International provides a simple procedure for determining the actual twist rate of your barrel.
Sinclair’s Simple Twist Rate Measurement Method
If are unsure of the twist rate of the barrel, you can measure it yourself in a couple of minutes. You need a good cleaning rod with a rotating handle and a jag with a fairly tight fitting patch. Utilize a rod guide if you are accessing the barrel through the breech or a muzzle guide if you are going to come in from the muzzle end. Make sure the rod rotates freely in the handle under load. Start the patch into the barrel for a few inches and then stop. Put a piece of tape at the back of the rod by the handle (like a flag) or mark the rod in some way. Measure how much of the rod is still protruding from the rod guide. You can either measure from the rod guide or muzzle guide back to the flag or to a spot on the handle. Next, continue to push the rod in until the mark or tape flag has made one complete revolution. Re-measure the amount of rod that is left sticking out of the barrel. Use the same reference marks as you did on the first measurement. Next, subtract this measurement from the first measurement. This number is the twist rate. For example, if the rod has 24 inches remaining at the start and 16 inches remain after making one revolution, you have 8 inches of travel, thus a 1:8 twist barrel.
Determining Barrel Twist Rate Empirically
Twist rate is defined as the distance in inches of barrel that the rifling takes to make one complete revolution. An example would be a 1:10″ twist rate. A 1:10″ barrel has rifling that makes one complete revolution in 10 inches of barrel length. Rifle manufacturers usually publish twist rates for their standard rifle offerings and custom barrels are always ordered by caliber, contour, and twist rate. If you are having a custom barrel chambered you can ask the gunsmith to mark the barrel with the twist rate.
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