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.
NOTE: All listed products are for sale to persons 18 years of age or older. No products are intended for use by minors.
1. Graf & Sons — Leupold Optics Rebates
⏺ Get big $100 or $50 Rebate on quality Leupold optics
Need a riflescope, spotting scope, or binocs for your fall hunt or shooting match? If so check out the Leupold Optics Rebates over at Graf’s. You can save $50 on BX-2 Alpine HD Binoculars and $100 on SX-2 Alpine HD Spotting Scopes and VX-5HD scopes. The SX-2 spotting scope has earned very positive reviews and the VX-5HD is great for long range hunting. Here are links for qualifying products: BX-2 Binoculars; SX-2 Alpine HD Spotters; VX-5HD Scopes.
2. Powder Valley — Popular Hodgdon, VV, Alliant Powders on Sale
⏺ Most popular accuracy powders in stock now at good prices
PowderValley.com has a large selection of highly desirable powders IN STOCK and discounted now through Wednesday, 9/27/2023. Powder Valley has Varget, H4350, Reloder 16, N133, N320, N550, AR Comp and many more top-tier propellants in stock now. If you need premium powders at very competitive prices, head over to Powder Valley immediately.
3. Midsouth — Lock-N-Load AP Auto Progressive Press, $549.99
⏺ Save $40 with sale and get 500 FREE Bullets
Progressive presses let you load ammo much more efficiently. The Lock-N-Load AP Loader Auto Progressive Press is on sale now for $549.99 ($40 off). This 5-station progressive features automatic indexing, priming, and ejection. The L-N-L AP Loader has a 5-station quick change bushing system that allows quick/easy cartridge type change-overs in less than 5 minutes. And right now, with this press purchase, Hornady provides 500 bullets for free.
4. Palmetto State Armory — 5.7×28 Rock Pistol Sale, $299.99
⏺ Impressive new cartridge in good pistol priced under $300.00
The 5.7×28 cartridge is a high energy defense round with reduced recoil compared to cartridges with big, heavy bullets. The PSA 5.7 Rock Pistol is a full-size polymer frame pistol with excellent ergonomics and great accuracy. Right now it is on sale for just $299.99 — a great price. Made from quality 416 stainless steel and advanced polymers, this 5.7 Rock pistol is a good choice for defense and gun games. Chambered in 5.7x28mm, the PSA 5.7 Rock is fed from a 23-round magazine and has a smooth Glock-style trigger. This pistol will accept Glock-compatible sights.
5. Creedmoor Sports — Crosman Challenger Air Rifle, $649.95
⏺ Accurate, match-proven, excellent starter competition air rifle
Airguns are more popular than ever for good reason. They’re inexpensive to shoot, can be used indoors, and you don’t need an FFL to acquire an air rifle. If you want an affordable, competition-grade air rifle, consider the Crosman Challenger 2021. This Sporter Class air rifle boasts an adjustable stock, swappable sidelever cocking handle, and competition sights. With good components and ergonomics, this Challenge rifle can compete with much more expensive rigs. This is a good choice for 3-position rifle training.
6. Amazon — Frankford Arsenal Case Prep Center, $120.30
⏺ Very capable case prep center with handy design
Case prep is critical for proper reloading but it can be a long and arduous process. Speed up your case prep with the Frankford Arsenal Case Prep System. The machine’s HSS cutters stay sharp for thousands of rounds to make trimming quick and easy and the heavy-duty motor and drivetrain are optimized for durability and performance. This prep center includes inside chamfer tool, deburr tool, large and small primer pocket cleaning tools, plus a trimmer with 3 collets and 6 shoulder bushings.
7. Midsouth — Frankford Arsenal Perfect Primer Seater, $61.48
⏺ Excellent Primer Seating Tool with very positive user reviews
Amazon has the Frankford Perfect Primer Seater Tool for $61.48 (14% Off). This is a GREAT primer seating tool. It has good feel, plenty of leverage, and the primer tray works well. Importantly, it has a click-adjust wheel for precise primer seating depth control. Read our Frankford Primer Seating Tool Product Review. The tool comes complete with 12 precision shell holders. A quick thumb release system allows you to switch from small to large primers easily. Plus there is a hard stop so you won’t over-crush a primer.
8. Midsouth — Aguila Rimfire Ammo Sale, from $3.19/50 rds
⏺ Incredibly low prices on Aguila .22 LR rimfire ammo
Shooting rimfire rifles and pistols is fun and affordable. Right now Midsouth is running an Aguila Rimfire Ammo Sale with great deals. Get reliable Aguila .22 LR ammo for as little as six cents per round (with $3.19 50rd box). There are many Aguila .22 LR rimfire ammo types on sale. Choose subsonic and supersonic, with a wide choice of bullet types.
9. Amazon — Digital Micrometer, $39.99
⏺ Good deal on precision inch + metric digital micrometer
A good micrometer is a key tool for accurately measuring cartridge components and gun parts. We found a good Digital Display Micrometer for just $39.99 on Amazon. This tool boasts a 0.0-1.0″ (0 to 25mm) range with with 0.00005″/0.001mm resolution and +/- 0.0001″ accuracy. This micrometer offers two measuring modes and is easy to operate.
10. Amazon — Wheeler P-Handle Tool Set, $48.71
⏺ Big discount on very complete set of drivers
If there’s one thing everyone needs in the workroom it’s a good set of hex and torq drivers. You can grab the Wheeler 30 Piece SAE/Metric Hex and Torx P-Handle Set for only $48.71 and have everything you need to work on guns and gear. This kit has SAE and Metric hex-type driver, plus Torx drivers, offering the full range of drivers your might need.
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Many short-range Benchresters have thought about converting their 6 PPC to shoot a 30BR for score matches, or a Dasher for mid-range (or even 1000-yard) games. That way you have a rifle that does double duty, giving you the most bang for your buck. Though an action with a PPC bolt won’t normally work with 30BR/6BR/Dasher cases with their larger .308-class rim (0.4728″ diameter), there is a pretty easy solution that allows you to cycle these bigger cartridges with a 6PPC-style bolt (designed to fit .220 Russian rims).
“Rebating case rims … lets you shoot a 30BR in score matches using your PPC action. All you need is a new barrel. This saves buying another bolt, receiver, or rifle.” — Butch Lambert
Butch Lambert of ShadeTree Engineering provided this tip. Butch notes that many 6 PPC benchrest group shooters also enjoy shooting in score matches. But to be really competitive in the BR for score game, that means shooting a 30BR, which has a wider, .308-class rim (0.4728″ diameter). Likewise, if you want to compete in 600-yard registered BR events or in varmint matches, you probably want to run a bigger case, such as the 6BR, 6mm Dasher, or 6-6.5×47. Those cartridges also have the larger 0.4728″ rims.
Rebate Your 30 BR Rims
To convert a PPC-boltface action to shoot bigger cases you can spend a ton of money to buy a new bolt. That can cost hundreds of dollars. The simpler solution is to turn down the diameter of the larger cases on a lathe. Butch explains: “We’ve seen plenty of interest in rebating case rims. This lets you shoot a 30BR in score matches using your PPC action. All you need is a new barrel. This saves buying another bolt, receiver, or rifle if you have a PPC boltface. Anyone who has access to a lathe can do this job pretty easily. Yesterday I turned 150 case in about an hour.”
At right is the lathe form tool Butch uses to rebate the case rims.
Cutting Head for Rebating Rims
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We like Lyman’s Electronic Digital Trigger Pull Gauge, which is faster and more precise than the previous model. The latest Lyman Pull Gauge measures trigger pull weights from 1 ounce to 12 pounds with resolution of 0.1 ounces (2.8 grams). It features an adjustable, 4-position rod which retracts into the gauge body. We think that anyone running match triggers below 2.5 pounds pull weight should have a gauge like this. Among the pull gauges on the market, we think the Lyman unit offers great performance for the price. This gauge has a $69.95 MSRP, but it’s now $54.99 at Midsouth and $56.06 on Amazon.
Features: More Precise Strain Gauge | Improved Grip Shape | Adjustable Rod Lengths
Lyman’s Electronic Digital Trigger Pull Gauge is designed to be the fastest and most accurate trigger pull gauge available. State-of-the-art strain gauge technology allows for repeatable accuracy of 1/10 ounce (2.8 grams). The gauge features a large, easy-to-read LCD display and you can switch from ounces to grams with the push of a button. The gauge can also deliver a pull weight average of the last 10 readings. That’s very helpful, particularly when working with factory triggers that may not be very consistent.
The Lyman Trigger Pull Gauge features a solid, collapsible rod with four locking positions. Being able to adjust length makes it easier to use the gauge with a wide variety of firearms — pistols, rifles, and shotguns. The locking feature prevents the rod from flexing when applying pressure to the trigger. When not in use, the rod conveniently collapses into the gauge body, making the whole unit more compact. The new Trigger Pull Gauge comes in an internally-padded plastic case that can be easily stored in a drawer or on your work bench.
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They say that a man can never have too much money or too much time. Darrell Jones would add that a man can never have too many BR-based rifles. Darrell had a fleet of BRs, in 22 BR, 6mm BR, 6.5 BR, 7 BR, and 30 BR. But he was intrigued by the potential of a rifle in the .257 caliber. Could it shoot as well as a 6mm BR? Could it challenge the more popular calibers in the highly competitive 600-yard benchrest game? Through careful research and component selection, Darrell created a 25 BR rifle that proves the viability of the 25 BR as a competition round. Pushing 115gr high-BC Berger bullets at 2837 fps, Darrell’s 25 BR “Peppermint” won first place in its very first match.
The Barely Bigger BR — Exploring the .25 Caliber Option
Rifle Report by Darrell Jones
I decided to build a 25 BR after several weeks of deliberation and ruling out a .257 Ackley Improved. Part of my dilemma was that I wanted to shoot F-Class competition at 600 yards, and I was unsure about the accuracy potential of the 25 BR. However, I currently have several BRs chambered in 22 BR, 6BR, 6.5 BR, 7 BR, and 30 BR and they all shoot exceptionally well at 600 yards. This lead me to believe a 25 BR should deliver fine accuracy, just like its other BR siblings. Why wouldn’t a 25 BR shoot accurately provided that I built it with the right components? The feasibility saga began. I began searching diligently for custom 25-caliber bullets. Unfortunately, there are not many 25-caliber custom bullet makers. I actually found only two custom bulletsmiths who produce the 25s. I did look at Fowlers and then looked at Bergers. Both Jeff Fowler and Berger made 110-grain flat-base bullets when I was looking. [Editor — this 110gr bullet is no longer listed by Berger]. The Berger 110gr FB bullets (.414 ballistic coefficient) shot very well out of my 12-twist 25-06 Ackley. However, I wanted to shoot a heavier bullet if possible. Berger makes a 25-caliber 115gr VLD boat-tail with a high ballistic coefficient. This needs a 10-twist barrel.
Panda Action, McMillan Stock, Weaver T-36
As you can see, I went with a Panda polished action and a weighted McMillan BR stock painted metallic silver with red candy cane stripes thus the name “Peppermint”. This gun actually does double duty now as a 25 BR and 6 PPC switch barrel. When I want to run the gun as a 6 PPC for short range, I simply screw on the PPC barrel, then swap in a bolt (fitting the PPC bolt face) from another Panda action I own. That’s one advantage of owning custom Kelbly actions! Don’t even think about exchanging bolts between factory guns. Kelbly rings and a Weaver T-36 fixed-power scope handle the optical duties while a Jewell trigger set at one ounce takes care of the firing mechanism.
Chambering for the .25 Caliber BR Wildcat
I wanted a chamber that would let me shoot both the 110s and the 115s. I took some time surfing the net looking for rental reamers that had suitable throat dimensions. I found that Elk Ridge Reamer Rentals had a 25 BR pilot reamer available. I called and Elk Ridge faxed me a reamer diagram that indicated it was designed to tight SAMMI specs. I asked how often was the reamer used and was told “not very often”.
I did want a minimum no-turn neck optimized for Lapua brass. The drawing indicated that the reamer would cut a .281″ neck and a throat of 1.0315″. This was very close to ideal, though I did have to turn two thousandths off the necks of Lapua 6BR brass after I necked it up. I resized using a .277″ bushing and the loaded rounds came out to be .279″. Realizing that this was in the ball park, I decided to go with the Elk Ridge Reamer and build a 25 BR that could shoot 110gr or 115gr bullets. Now the question was where to get a match-grade 25-caliber barrel. I called quite a few of the custom barrel-makers, including BlackStar Barrels in Texas (no longer operating). I have had wonderful success with the BlackStar barrel on my 6BR “Chantilly” — it delivered great accuracy and impressive velocities. Since the 25 BR was so similar, I went with another BlackStar. I ordered a 10-twist, 6-groove, 1.250″-diameter straight-contour tube.
After chambering, the barrel finished at 1.245″ diameter and 27.5″ inches with an 11° crown. I actually had the throat lengthened to accept both Berger 110gr and 115gr bullets. The bases of the FB 110-grainers sit flush with the neck-shoulder junction, when they are seated .010″ into the lands. With the longer 115gr VLDs, the bottom of the bearing surface (i.e. start of boat-tail) is just about even with the neck-shoulder junction.
Accurate Load Development
The barrel broke in easily with just 10 shots, using a “shoot one and clean” process. The load I started with was 31.5 grains of Varget with CCI 450 primers. The Berger 110s and Berger 115s had the same Point of Impact (POI) at 100 yards. However, the 115s impacted two inches higher at 600 yards with the same load. That shows the benefits of a higher BC. Pushed by the CCI 450s and 31.5 grains of Varget, the 115-grainers were running about 2837 FPS. I boosted the load up to 32.0 grains but I noticed primer cratering, so I backed off, settling on 31.5 grains for the 115gr Berger VLD.
Peppermint Wins at 600 Yards
For her debut in competition, I took “Peppermint” to our local 600 yard F-class match. Shooting the Berger 115s with 31.5 grains Varget, she won with a perfect score of 200 with 14 Xs. At my club, we use a SR3 target. The X-Ring measures 3″ in diameter and the 10-Ring measures 7″. At the match there were some very good shooters with top-flight custom rifles in accurate calibers such as 6.5-284 and 22 Dasher. I was very fortunate to come out on top, but I give the credit to Peppermint’s good bench manners and outstanding accuracy.
As you can see from the target, “Peppermint” is a very accurate rifle that has proven herself in competition. It takes a good gun to finish “on top” in her very first match. So far, I’m very happy with the project, and more than satisfied with the accuracy of the 25 BR. This is definitely a worthy cartridge for Egg Shoots, 500m varmint matches, and the 600-yard F-Class game.
BR-Based Cartridge Comparison
CALIBER
22 BR
6mm BR
25 BR
6.5 BR
7 BR
30 BR
Bullet
80gr SMK
107gr SMK
115gr Berger
107gr SMK
130gr SMK
118gr BIB
BC
.420
.527
.522
.420
.391
na
Load Grains
31.0 H4350
30.0 Varget
31.5 Varget
32.0 Varget
34.0 AA2460
34.0 H4198
Barrel Length
27″
27″
27.5″
27.5″
28″
24″
Velocity
3100 fps
2880 fps
2837 fps
2851 fps
2719 fps
2970 fps
Comparing the BR-Based Variants
Now that I have several calibers in the BR cartridge family, (22 BR, 6mm BR, 6.5 BR, 7 BR, and a 30 BR), it is my humble opinion that they each have their own place. A varmint hunter’s dream, the 22 BR can push a bullet faster and more accurately than the 22-250. With an 8-Twist barrel, the 22 BR can send an 80gr SMK to 600 yards with extreme accuracy.
The 6 BR can do it all. The 6mm caliber offers a wide variety of quality bullets suitable for any shooting situation. All the major custom barrel makers produce outstanding 6mm barrels in a full range of twists. Moreover, since the 6 BR cartridge is so popular, there is a great store of knowledge about reloading for the 6 BR. It is easy to find a load that will shoot superbly in any bullet weight.
The 25 BR has proved to be easily tuneable, proficient and not fickle. You can obtain extreme accuracy without great effort in load development. The 115gr Berger offers a good high-BC projectile for this caliber, making the 25 BR a viable alternative to the 6 BR. As I’ve shown, it is competitive with a 6 BR in head to head competition.
Compared to the 25 BR, the 6.5 BR has a small edge in ballistics. However, there are not many light bullet choices available, especially from custom makers. The 123gr Lapua Scenar is an excellent bullet with a .547 stated BC, but it may be a bit heavy for the case capacity.
The 7 BR was designed for silhouette shooting, and it excels at that task. The 7 BR can push a 130 grain bullet fast enough to knock over the steel silhouettes at 500 meters with real consistency.
The 30 BR is nothing less than outstanding. The 30 BR is now the dominant cartridge on the benchrest Score-shooting circuit. It is also highly accurate for group shooting at 200 yards and very capable of winning a 600-yard F-Class match. Barrel life of over 6,000 rounds is realistic.
I like all the “flavors” of BR derived from the 6mm BR Norma case. However, if I could only have one BR in my safe, give me my 8-Twist, 6 BR “Chantilly” and I will be a happy camper. The final point I would make is if a cartridge is stamped BR on the case, it will shoot extremely accurately if you can.
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September 23, 2023, was National Hunting and Fishing Day (NHFD). We’re proud to recognize how important hunting is for millions of Americans — as a source of food for families and as an important connection with nature and the outdoors. The NFHD website has helpful resources for hunters, and in this article we provide links for Where to Hunt, How to get Hunting Licenses, and Hunter Education.
NHFD was first established by President Nixon in 1972. According to NationalToday.com, NHFD’s “roots go back more than 100 years to President Theodore Roosevelt, who introduced the first laws regulating the hunting of wildlife in the United States.”
This month we hope some of our readers can take new shooters afield and introduce them to hunting. Many hunters receive their first introduction to hunting from family or friends as a tradition passed down from generation to generation. There are over 9.2 million hunters in the United States.
To have a successful hunt you must first get to areas where game thrives. Finding the right places to hunt is essential. The NSSF offers a nationwide Where-to-Hunt database of hunting areas. You can click on a particular state, then specify the specicies you wish to hunt. This is a very useful resource.
In most states, when hunting game animals, you’ll need a hunting license and/or zone permit. The Federal Fish & Wildlife Service has state-by-state listing for hunting licenses on FWS.gov. Click the box below to learn how to get hunting licenses in your region.
For all hunters, whether they have mentors to guide them or not, the most important first step into the woods begins with a state-certified hunter education course. Click the box below to see hunting education opportunities around the nation.
Game Resources — To learn more about different game species, click these NSSF links:
To help you prepare for a fall hunt, here is a free, printable Deer Practice target. Hone your skills on a trio of bucks with a red bullseye centered on the animals. You can print the targets in black and white, but they look best in color. Right-click the image below to download a FREE printable PDF file.
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The last half-inch or so of your barrel is absolutely critical. Any damage (or abnormal wear) near the crown will cause a significant drop-off in accuracy. Here are ways you can check the end of your barrel, using a common Q-Tip.
Use Q-Tip for Barrel Inspection
To find out if you have a burr or damage to your crown, you can use an ordinary Q-tip cotton swab. Check the edges of the crown by pulling the Q-tip gently out past the edge of the crown. If you have a burr, it will “grab” the cotton and leave strands behind.
Larry Willis has another way to use a Q-Tip: “Here’s a neat trick that will surprise you with how well it works.” Just insert a Q-Tip into your barrel (like the picture below), and it will reflect enough light so that you can get a real good look at the last half inch of rifling and the crown of your barrel. In most cases you’ll find that this works much better than a flashlight. Larry tells us: “I’ve used this method about a jillion times. Q-Tips are handy to keep in your cleaning supplies anyway. This is a good way to judge approximately how well you are cleaning your barrel when you’re at the range. It’s also the best way to examine your barrel when you’re in the field.”
Ever wondered how factory ammunition is produced, from start to finish? How are brass cases made, how are bullets created, and how are finished cartridges produced on automated assembly lines? Today’s video showcase features six major factories that, collectively, produce bullets, powder, and finished ammo. We start with the Berger Bullet plant, follow by Vihtavuori powder production in Europe. Then we show the Remington (now Vista Outdoor) ammo plant in Utah, along with a Federal plant that produces rimfire ammunition. Last but not least, there’s an excellent, very informative video from the Norma ammo factory, plus a Hornady ammo plant video.
Bullets being seating at Hornady ammo factory.
Berger Bullets Factory Tour — Made in USA
In this video, Recoil TV takes a behind-the-scenes look at Berger Bullets, and how the outstanding, match-winning Berger bullets are created. The video covers the entire process — from raw materials, to the placement of bullet cores inside jackets, to the final ultra-consistent and uniform projectiles. To see the complete line of Berger Bullets, with full Ballistic data, visit BergerBullets.com
Vihtavuori Powder Production in Europe
Vihtavuori produces some of the most consistent, high-quality powder on the planet. Vihtavuori powders have been used to set world records and win countless championships in multiple disciplines. This excellent video goes inside Vihtavuori’s European production centers. It is really fascinating — you see how extruded powder starts with long spaghetti-like strings, before being finalized into the tiny sticks that we load.
Along with the powder production process, this video includes the entire VV production line, so you see how powder bottles are filled with powder and the tops of the bottles are secured by automated machines.
Remington Ammo Factory (Now Operated by Vista Outdoor)
This SHWATteam video visits the Remington ammunition plant in Arkansas. Vista Outdoor, the company that produces Federal, Speer and CCI ammo, purchased Remington’s ammunition business in Lonoke, Arkansas. Including the new high-tech plant in the back, this facility has the equivalent of 13+ football fields (1200 acres) under roof at its ammo plant, with over 1100 employees. Production capacity is impressive. When running at maximum output, this Remington ammo plant can crank out a staggering 7,000,000+ rounds every day. To produce that volume of ammunition, the facility needs a huge amount of resources: one million pounds of copper per month and 124,000 pounds of lead per day. Remington started manufacturing ammunition at this Lonoke facility in 1970, but some of the machines have been churning out ammo since long before.
Norma Factory Tour
Guys — honestly, if you do anything today on this site, watch this video. You won’t be disappointed. Guaranteed. This is a very informative (and surprisingly entertaining) video. Every serious hand-loader should watch this video to see how cartridge cases are made. The camera work and editing are excellent — there are many close-ups revealing key processes such as annealing and head-stamping.
VERY Informative Video Show Cartridge Brass and Ammunition Production:
Norma has released a fascinating video showing how bullets, brass, and ammunition are produced at the Norma Precision AB factory which opened in 1902. You can see how cartridges are made starting with brass disks, then formed into shape through a series of processes, including “hitting [the cup] with a 30-ton hammer”. After annealing (shown at 0:08″), samples from every batch of brass are analyzed to check metal grain structure and hardness. Before packing, each case is visually inspected by a human being (3:27″ time-mark).
Federal Rimfire Ammunition Production
Field & Stream Tours Federal Ammo Plant in Minnesota
A reporter for Field & Stream recently got a chance to tour the Federal ammunition production facility in Anoka, Minnesota. This large plant produces both rimfire and centerfire ammunition. While touring the plant, the reporter was allowed to capture video showing the creation of .22 LR rounds from start to finish. This is a fascinating video, well worth watching. Watch and learn how rimfire ammo is made.
Note to Viewers — After Starting Video, Click Speaker Icon to HEAR audio!
This revealing video shows all phases of .22 LR ammo production including cupping, drawing, annealing, washing, drying, head-stamping, priming, powder charging, bullet seating, crimping, waxing, inspection, and final packaging. We recommend you watch the video from start to finish. You’ll definitely learn some new things about rimfire ammo.
Hornady Ammunition Factory
If you wonder how ammo is made, starting with raw metal, check out this video from Hornady. It shows how bullet jackets are formed from copper, followed by insertion of a lead core. The jacket is then closed up over the core with the bullet taking its final shape in a die (a cannelure is applied on some bullet types). Next the video shows how cartridge brass is formed, starting with small cups of brass. The last part of the video shows how cases are primed and filled with powder, and how bullets are seated into the cases, using an automated process on a giant assembly-line.
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Here are two different bullet types, seated to the same CBTO length, but different COAL. Note the shiny scratches on the bullets made by the comparator tool which indicates a point on the bullet ogive near where the ogive will engage the rifling.
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2 by Bryan Litz forBerger Bullets. Part One of this series focused on the importance of COAL in terms of SAAMI standards, magazine lengths, seating depths, and pressure levels. Another measure of length for loaded ammunition is highly important to precision, namely Cartridge Base to Bullet Ogive Length (CBTO).
Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.
Look at Figure 2. Suppose the bullet was seated out of the case to the point where the base of the bullet’s nose (ogive) just contacted the beginning of the riflings (the lands) when the bolt was closed. This bullet seating configuration is referred to as touching the lands, or touching the riflings and is a very important measurement to understand for precision hand-loading. Due to the complex dynamics of internal ballistics which happen in the blink of an eye, the distance a bullet moves out of the case before it engages the riflings is highly critical to precision potential. Therefore, in order to systematically optimize the precision of his handloads, it’s critically important that the precision hand-loader understands how to alter bullet seating depth in relation to the barrel rifling. Part of the required knowledge is understanding how to accurately and repeatably measure the Cartridge Base To Ogive (CBTO) dimension. This is explained in the FULL ARTICLE.
Bryan Litz offers an extended discussion on how to measure CBTO using different tools and methods, including the Hornady OAL gauge. You can read this discussion in the full article found on the Berger Bullets website. CLICK HERE to Read Full Article.
Why Not Use CBTO as a SAAMI Standard?
If CBTO is so important to rifle accuracy, you might ask, “Why is it not listed as the SAAMI spec standard in addition to COAL?” There is one primary reason why it is not listed in the standard. This is the lack of uniformity in bullet nose shapes and measuring devices used to determine CBTO.
Benefits of Having a Uniform CBTO
There is another aspect to knowing your CBTO when checking your COAL as it pertains to performance. With good bullets, tooling, and carefully-prepared cases you can easily achieve a CBTO that varies less than +/- .001″ but your COAL can vary as much as .025″ extreme spread (or more with other brands). This is not necessarily bad and it is much better than the other way around. If you have a CBTO dimension that varies but your COAL dimension is tight (within +/- .002″) then it is most likely that your bullet is bottoming out inside the seater cone on the bullet tip. This is very bad and is to be avoided. It is normal for bullets to have precisely the same nose shape and it is also normal for these same bullets to have nose lengths that can vary as much as .025″.
Summary of Cartridge Base To Ogive (CBTO) Discussion
Here are four important considerations regarding bullet seating depth as it relates to CBTO:
1. CBTO is a critical measurement to understand for handloaders because it’s directly related to precision potential, and you control it by simply setting bullet seating depth.
2. Tools and methods for measuring CBTO vary. Most of the measurement techniques have pitfalls (which may give rise to inconsistent results) that you should understand before starting out.
3. A CBTO that produces the best precision in your rifle may not produce the best precision in someone else’s rifle. Even if you have the same rifle, same bullets, same model of comparator gauges, etc. It’s possible that the gauges are not actually the same, and measurements from one don’t translate to the same dimension for another.
4. Once you find the CBTO that produces the best precision in your rifle, it’s important to allow minimal variation in that dimension when producing quality handloads. This is achieved by using quality bullets, tooling, and properly preparing case mouths and necks for consistent seating.
Many barrel-makers mark the twist rate and bore dimensions on their barrel blanks.
Does muzzle velocity change with faster or slower barrel twist rates? Absolutely, but much less than you might think. Faster twist rates do slow down bullets somewhat, but the speed loss is NOT that significant. With Bartlein .308 Win barrels of identical length and contour, a 1:12″-twist barrel was only 8 fps faster than a 1:8″-twist barrel. That was the result of testing by Applied Ballistics.
The Applied Ballistics team tested six (6) same-length/same-contour Bartlein barrels to observe how twist rate might affect muzzle velocity. This unique, multi-barrel test is featured in the book Modern Advancements in Long Range Shooting, Vol. 1. That book includes other fascinating field tests, including a comprehensive chronograph comparison.
Barrel Twist Rate vs. Velocity — What Tests Reveal by Bryan Litz
When considering barrel twist rates, it’s a common belief that faster twist rates will reduce muzzle velocity. The thinking is that the faster twist rate will resist forward motion of the bullet and slow it down. There are anecdotal accounts of this, such as when someone replaces a barrel of one brand/twist with a different brand and twist and observes a different muzzle velocity. But how do you know the twist rate is what affected muzzle velocity and not the barrel finish, or bore/groove dimensions? Did you use the same chronograph to measure velocity from both barrels? Do you really trust your chronograph?
Summary of Test Results
After all the smoke cleared, we found that muzzle velocity correlates to twist rate at the average rate of approximately 1.33 FPS per inch of twist. In other words, your velocity is reduced by about 5 FPS if you go from a 1:12″ twist to a 1:8″ twist. — Bryan Litz
Savage Test Rifle with Six Bartlein Barrels
Most shooters don’t have access to the equipment required to fully explore questions like this. These are exactly the kinds of things we examine in the book Modern Advancements in Long Range Shooting, Vol. 1. In that book, we present experiments conducted in the Applied Ballistics lab. Some of those experiments took on a “Myth Buster” tone as we sought to confirm (or deny) popular pre-conceptions. For example, here’s how we approached the question of barrel twist and muzzle velocity.
Six .308 Win Barrels from Bartlein — All Shot from the Same Rifle
We acquired six (6) barrels from the same manufacturer (Bartlein), all the same length and contour, and all chambered with the same reamer (SAAMI spec .308 Winchester). All these barrels were fitted to the same Savage Precision Target action, and fired from the same stock, and bench set-up. Common ammo was fired from all six barrels having different twist rates and rifling configurations. In this way, we’re truly able to compare what effect the actual twist rate has on muzzle velocity with a reasonable degree of confidence.
Prior to live fire testing, we explored the theoretical basis of the project, doing the physics. In this case, an energy balance is presented which predicts how much velocity you should expect to lose for a bullet that’s got a little more rotational energy from the faster twist. In the case of the .30 caliber 175 grain bullets, the math predicts a loss of 1.25 fps per inch-unit of barrel twist (e.g. a 1:8″ twist is predicted to be 1.25 fps slower than a 1:9″ twist).
Above, data shows relationship between Twist Rate and Muzzle Velocity (MV) for various barrel twist rates and rifling types. From fast to slow, the three 1:10″ twist barrels are: 5R (canted land), 5 Groove, 5 Groove left-hand twist.
We proceeded with testing all 6 barrels, with twist rates from 1:8″ to 1:12″. After all the smoke cleared, we found that muzzle velocity correlates to twist rate at the average rate of approximately 1.33 fps per inch of twist. In other words, your velocity is reduced by about 5 fps if you go from a 1:12″ twist to a 1:8″ twist. [Editor: That’s an average for all the lengths tested. The actual variance between 1:12″ and 1:8″ here was 8 FPS.] In this case the math prediction was pretty close, and we have to remember that there’s always uncertainty in the live fire results. Uncertainty is always considered in terms of what conclusions the results can actually support with confidence.
This is just a brief synopsis of a single test case. The coverage of twist rates in Modern Advancements in Long-Range Shooting Vol. 1 is more detailed, with multiple live fire tests. Results are extrapolated for other calibers and bullet weights. Needless to say, the question of “how twist rate affects muzzle velocity” is fully answered.
Other chapters in the book’s twist rate section include: · Stability and Drag — Supersonic
· Stability and Drag — Transonic
· Spin Rate Decay
· Effect of Twist rate on Precision
Other sections of the book include: Modern Rifles, Scopes, and Bullets as well as Advancements in Predictive Modeling. This book is sold through the Applied Ballistics online store. Modern Advancements in Long Range Shooting is also available as an eBook in Amazon Kindle format.
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Larry Medler has come up with a smart little invention — a simple, inexpensive Empty Chamber Indicator for rimfire rifles. It is made from a section of plastic “weed-wacker” line and a wooden ball from a hobby shop. Larry says he was inspired by Juniors who used something similar for their 17-Caliber Air Rifles.
How to Make the Empty Chamber Indicator
Construction Method: First, drill a 7/64″ diameter hole all the way through the 1″-diameter wooden ball. Then enlarge half of that 1″-long hole using a 13/64” diameter drill. Next insert an 8″ piece of heavy duty (0.095″ diameter) weed wacker line through the ball, leaving about 2″ on the side with the bigger-diameter hole. Then, with the short end of the line, fold over the last half-inch so the line is doubled-over on itself. Then slide the line into the ball, stuffing the doubled-over section through the 13/64″ (large) hole. Finally, pull the longer end of the line until the doubled-over section is flush with the outside of the ball. This gives you a sturdy line attachment without messy adhesives. When the assembly’s complete, hold the ECI by the tail and dip the ball in yellow paint. If you’re making more than one ECI, you can drill horizontal holes in a spare block of wood and use that as a drying rack.
At a Rimfire Sporter match like this, all shooters must have an Empty Chamber Indicator.
The Empty Chamber Indicator for Smallbore Rifles
Larry explains: “At all Highpower rifle matches, silhouette matches, and other shooting events I have attended, Open Bore Indicators (OBI), or what are now called Empty Chamber Indicators (ECI) have been mandatory. The NRA’s yellow ECI for Highpower rifles is easy to use and has been well-received by the shooters. However, I had not seen a truly workable ECI for 22 rimfire rifles — until I visited Michigan’s Washtenaw Sportsman’s Club where I saw juniors using ECIs for their 17 Caliber Air Rifles. Someone at the club made the empty chamber indicators by attaching an 8″ piece of weed wacker line to a 1″-diameter wooden ball, painted bright yellow. I now make similar ECIs for the 22 rimfire silhouette matches I run.”
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Need a top-notch Ballistics App for your iPhone, iPad, or iPod? Start with Ballistic: Advanced Edition (AE), the number 1 (i.e. most installed) App for iOS systems (iPhones and iPads). Ballistics AE (Advanced Edition) is the most popular iOS ballistics program for many good reasons. It offers a full feature set with Ballistic Solver, Ballistic Comparison (with up to 8 projectiles), Target Log (records group sizes), Advanced WindKit, and more. The Ballistic: Advanced Edition software is easy to use, with nice controls. Underneath it all is the proven JBM Ballistics calculator. And here’s the kicker — this excellent mobile App software is now FREE to download and install on iPhones and iPads!
This Video Explains How to Set Up and Use Ballistic: Advanced Edition
Full-featured and easy to use, Ballistics AE has been refined over many years, and it supplies rock-solid solutions derived from JBM Ballistics solver (created by James B. Millard). Unlike some other Apps, Ballistics AE is STABLE on iPhones (with various OS levels). What’s cool is that Ballistics AE is now available for FREE for both iPhones and iPads. This software is now provided by Federal Premium Ammunition, with in-App purchase functionality.
We’ve used the Ballistic: Advanced Edition program on an iPhone 5S, iPhone 6, and iPad, and it performed well. Here are some of the features we liked:
1. Mirrors output from online version of JBM Ballistics we often use for initial calculations.
2. Controls are simple to use and (mostly) intuitive.
3. Handy comparison feature lets you compare ballistics for different projectiles side by side.
4. Advanced Wind Kit allows you to account for complex wind situations.
5. Projectile and BC Databases are very comprehensive.
6. Software is regularly updated to match Apple OS changes.
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Bushnell offers Match Pro ED 15×56 Binoculars designed for PRS/NRL competition. These 15X Match Pro ED binoculars have a unique box-style MilRad reticle for ranging and determining shot locations. These new-for-2023 Match Pro ED Binoculars combine high-magnification binocular lenses with an MRAD-based reticle for ranging, target sizing, and shot correction. The benefit is that this 15X binocular optic could replace a bigger, heavier reticle-equipped spotting scope. This Match Pro ED Binocular can be quickly mounted on a tripod for enhanced stability. We recommend that because it is pretty hard to hold a 15X optic very steady with hands alone.
The Match Pro ED’s offset SHOT-CALL reticle, located in the right barrel, has a dedicated focus adjustment and can be rotated for leveling after IPD (interpupillary distance) adjustment (i.e. how far the eyepieces are spread apart). Users can secure their preferred IPD with the included BRIDGESET stabilizer, which ensures the binocular is set for quick use and is stable when mounted on a tripod. Claimed light transmission is 92%. Suggested MSRP for the Match Pro ED 15×56 binoculars is $699.99.
Our friend Jonathan Ocab reviewed the new Match Pro ED 15x56mm binoculars: “Bushnell Optics showed off their new Match Pro ED 15×56 binocular, which is based off of their Forge binocular design. The Forge 15×56 has a good reputation as a budget-friendly binocular with good performance at its price range. The Match Pro ED 15×56 is a hefty binocular with a magnesium chassis coming in at 51 ounces with what is dubbed the SHOT-CALL MRAD reticle. The reticle [rotates in the right barrel] so that it can be leveled for the user’s eyes after the barrels are adjusted to the pupil distance.”
Jonathan added: “My initial impressions of this binocular are positive. It is definitely a bigger, heavier binocular and is not going to be one for field use. This is definitely the type of binocular one would employ on the range at NRL/PRS matches to spot for a shooter.” CLICK HERE for full SHOT Show 2023 Optics report by Jonathan Ocab.
In this video, top PRS shooter Robert Brantley explains the features of the Match Pro ED 15X binoculars. He says these can replace a spotting scope, and he says the Shot-Call Reticle works very well for both ranging and calling hit locations.
Recoil Web also did a review of these new 15×56 binoculars stating: “The new Bushnell Match Pro ED 15×56 binoculars [offering] is a big deal, but maybe just to a niche crowd. For a long time, spotting scopes have often come with a MIL or MOA reticle in the eyepiece so one could spot shots at long range and call corrections or for use in ranging a target if a laser rangefinder wasn’t available. With a reticle in the right barrel, you get a MIL grid for ranging and shot correction like a spotting scope but the [wide] field of view and outstanding glass of the binoculars.”
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