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September 12th, 2025

Stainless Steel & Corrosion Resistance — What You Need to Know

Benchmark stainless steel barrel barrels match
Most modern match rifle barrels are stainless steel alloy. These are from Benchmark Barrels.

Though some grades of stainless are more corrosion-resistant, ALL varieties of stainless steel can rust if they are not handled and stored properly.

Some folks feel that they don’t have to worry about rust and corrosion on stainless steel barrels, actions, and other components. That’s not really true. “Stainless” is a bit of a misnomer. First, there are different types of stainless steel alloys, with different degrees of rust resistance. 300 series stainless is more corrosion resistant than the 416 stainless commonly used in barrels. The composition (by percentage weight) of 416 stainless is 0.15% carbon, 12-14% chromium and the rest iron. 416 stainless steel lacks the roughly 10% nickel content that makes the 300 series more corrosion resistant in atmospheric conditions. But because 416 handles pressure better and is easier to machine (than 300 series steel), 416 stainless remains the better choice for barrels.

stainless steel barrel Techshooter

Though some grades of stainless are more corrosion-resistant, ALL varieties of stainless steel can rust if they are not handled and stored properly. Forum reader Kells81 observed: “Wanna see some rusted stainless? Go to the big “C” brand store in Ft. Worth. Every stainless gun they have on the used gun rack is rusted.” Tom Easly of TRE Custom explains: “Sweat is very corrosive. Sweat and blood will rust many stainless steels. I hate to handle my guns or drip on them when I sweat. It really helps to just wipe them good with a wet rag, dry and wipe on a light coating of gun oil. I think most stainless barrels are made from type 416 stainless, and it is generally pretty corrosion resistant, but not when exposed to sweat, blood, or chlorates (corrosive priming), and some other electrolytes.”

Forum member Jacob, who is studying materials science at LSU, provides this technical information: “The basic resistance of stainless steel occurs because of its ability to form a protective coating on the metal surface. This coating is a ‘passive’ film which resists further ‘oxidation’ or rusting. The formation of this film is instantaneous in an oxidizing atmosphere such as air, water, or other fluids that contain oxygen. Once the layer has formed, we say that the metal has become ‘passivated’ and the oxidation or ‘rusting’ rate will slow down to less than 0.002″ per year (0.05 mm per year).

Unlike aluminum or silver, this passive film is invisible in stainless steel. It’s created when oxygen combines with the chrome in the stainless to form chrome oxide which is more commonly called ‘ceramic’. This protective oxide or ceramic coating is common to most corrosion resistant materials.

Halogen salts, especially chlorides, easily penetrate this passive film and will allow corrosive attack to occur. The halogens are easy to recognize because they end in the letters ‘ine’. Listed in order of their activity they are: fluorine, chlorine, bromine, iodine, astatine.

These are the same chemicals that will penetrate Teflon and cause trouble with Teflon coated or encapsulated O-rings and/ or similar coated materials. Chlorides are one of the most common elements in nature and if that isn’t bad enough, they’re also soluble, active ions. These provide the basis for electrolytes. The presence of electrolytic solutions can accelerate corrosion or chemical attack.”

CONCLUSION: Stainless steel barrels and components won’t rust nearly as fast as blued steel, but you still have to take precautions — particularly removing sweat and corrosive salts from the barrel. Also, don’t let moisture build up inside or outside of the barrel. We recommend wiping your barrels and actions with Eezox, or Corrosion-X after each use. These are both extremely effective rust-fighters that go on thin, without leaving a greasy residue. (Eezox leaves a clear finish, while Corrosion-X has a slightly waxy finish.) Also store your guns in Bore-Store bags when the guns go in the safe. Bore-Stores wick away moisture, and the synthetic fleece inner surface is treated with rust-fighting chemicals. Bore-Stores also protect your guns against dings and scratches.

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September 12th, 2025

Hunting Safety Checklist — Prepare for Fall Hunting Season

Hunting Safety Checklist family safe hunter
Elk Hunt with Horn Fork Guides, Ltd., in Colorado.

national hunting fishing day NSSF hunter deer elk gameSeptember 27, 2025 is National Hunting & Fishing Day. The annual celebration takes place on the the fourth Saturday of September every year. National, regional, state and local organizations will run thousands of “open house” hunting- and fishing-related events around the country. Events will include Fishing Derbys, Hunting Expos, Wing-shooting tournaments, and much more.

Hunting Safety Checklist
A good hunt begins with preparation. And during the hunt, safety is a key priority. To help hunters, the National Shooting Sports Foundation (NSSF) has created a Safety Checklist for hunters. This Hunting Safety Checklist, produced as part of the NSSF’s “Hunt S.A.F.E.” campaign, helps hunters follow good, safe practices in the field and at home.


Download NSSF Hunting Safety Checklist »

Hunting Safety Checklist family safe hunter
hunting safety day checklist
Elk photo courtesy Colorado Parks and Wildlife.

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September 11th, 2025

Remembering the 9/11 Attack after 24 Years

Remembrance 9/11 attack world trade center
Image from Creedmoor Sports

“Freedom is never more than one generation away from extinction. We didn’t pass it to our children in the bloodstream. It must be fought for, protected, and handed on for them to do the same, or one day we will spend our sunset years telling our children and our children’s children what it was once like in the United States where men were free.” — Ronald Reagan

Today marks the 24th anniversary of a tragic day in American history. Much like December 7th, 9/11 remains a “date which will live in infamy”. On this 11th day of September 2025, we think it is good for Americans to honor the sacrifice of the first responders who went to the World Trade Center (WTC) and who lost their lives. And we must remember all those who died as the towers collapsed. It is also a good time to remember those key values for which this nation stands — freedom, liberty, and justice for all. In a modern world where media sources and politicians seek to divide Americans and create hostility, the shared memory of 9/11 can perhaps serve to unite us.

Forum member Charlie NC posted: “Everybody remembers where they were when the attacks happened, and the emotions they felt. God bless the victims who died that day, and those who followed in the pursuit of justice. But at a terrible time our country was more united than at any other point in my lifetime. Hopefully may we regain that harmony again under better circumstances.”

Remembrance from 24 Years Ago — Days Before the Attack
Forum member David Joe was in New York City in September 24 years ago. David had actually been in the World Trade Center with his family just a few days before the attack. Here is his perspective on how the tragedy of 9/11 has changed life in America…

24 Years Ago at the World Trade Center…
Twenty-three years and a week ago, my wife, son, and unborn daughter spent five hours at the World Trade Center. We ate, took pictures everywhere, watched the tilting platform movie, pressed souvenir pennies, went to the top, talked to the employees and watched birthday flowers being delivered up the escalator to one of them. And that’s what we first thought about on the morning of 9/11…

Remembrance 9/11 attack world trade center

By the evening of 9/11, I knew the world was different, and always would be. In all the years that have gone by, families like mine eventually travelled again, grew up and recognized at least once a year, the magnitude of the events of that day. Some think about it all the time and became more vigilant, and that is certainly, I hope, good.

Other families were directly involved daily in preventing terrorism from coming home again. Thousands of families lost relatives that day, and many more in the years after.

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September 11th, 2025

Savage Hunting Rifle Giveaway Contest with Gunbroker

savage gunbroker elite precision 110 hunting rifle contest september 2025

GunBroker & Savage Arms Offer Precision Backcountry Rifle Prizes
With hunting season right around the corner, Savage Arms and GunBroker.com have kicked off the Savage Arms Precision Backcountry Hunting Sweepstakes, giving hunters the chance to win one of four handsome, rugged hunting rifles. Entries are open now through September 30, 2025. Participants can return daily for bonus entries that boost the odds of winning.

“Backcountry hunts demand preparation, reliable gear, and confidence,” said Beth Shimanski, Savage Arms VP of Marketing. “The 110 High Country and Axis 2 Pro Woodland deliver the accuracy and rugged finishes serious hunters demand. We’re excited to partner with GunBroker to put these rifles in the hands of four lucky winners just in time for fall.”

Allen Forkner, Gunbroker Brand Management VP, noted: “This sweepstakes helps hunters gear up with proven Savage platforms and reminds everyone to come back every day in September for bonus entries.”

Prizes — Four Rifles (Two Savage 110s; Two Savage Axis IIs)

Grand Prize #1: Savage 110 High Country Rifle, .270 Win — $1,279 MSRP
Grand Prize #2: Savage 110 High Country Rifle, .308 Win — $1,279 MSRP

Runner-Up Prizes (2): Savage Axis II Pro Woodland Rifles, 6.5 Creedmoor — $599 MSRP each

Total value of all prizes: $3,756.00.

savage gunbroker elite precision 110 hunting rifle contest september 2025

How to Enter Contest

Enter the Savage Arms Precision Backcountry Hunting Sweepstakes at GunBroker.com/c/sweepstakes. You can re-visit every day through September 30th to earn bonus entries. Full details and entry form are available at GunBroker.com/c/sweepstakes.

Fine Print Contest Rules
No purchase necessary. Void where prohibited. Open to eligible U.S. residents. Sweepstakes runs through September 30, 2025. Odds of winning depend on number of eligible entries received. Firearm transfers must be completed through a licensed FFL in accordance with all applicable laws. See Official Rules at GunBroker.com/c/sweepstakes for eligibility, entry methods and prize details.

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September 11th, 2025

How to Develop a Good Load for Your Hunting Rifle

Keith Glasscock winning Wind .308 Winchester Win .223 Rem load development

Hunting season kicks off this month in many parts of the USA. If you have a new hunting rifle or need to develop a load for your rig with a new choice of bullets and/or powder, this article can help. Ace shooter Keith Glasscock explains how to develop a good load for a hunting rifle or varmint rifle.

Keith is an outstanding competitive shooter, who has finished second at the F-Class National Championships (F-Open) multiple times. Keith is also a skilled wind coach who runs the popular Winning in the Wind YouTube Channel. Along with his interest in mid-range and long-range F-Class competition, Keith also enjoys game hunting and varmint adventures.

Developing accurate hand-loaded ammo for hunting and varmint rifles involves procedures that may be a bit different than load testing for a match rifle. You want to be efficient, and use the types of brass and bullets you’ll be using on the hunts. In two recent videos, Keith shows how he developed good, accurate loads for a .223 Rem varmint rifle and a .308 Win hunting rifle.

.223 Rem Load Development — Powder Charge and Seating Depth

In the first video, Keith covers the load development process for a Remington 700 bolt-action varmint rifle chambered in .223 Remington. Keith starts by full-length sizing the brass. Then he experimented with powder charge weights, and came up with a promising load of 24.7 grains of Alliant AR Comp with Hornady 50gr A-Max bullets.

Next Keith experimented with seating depths (see 5:30-6:100) and found that accuracy improved as he changed OAL length in .005 increments. Keith ended up with 2.270″ with a 3-shot group in the twos! This video shows the importance of testing your bullet choice at various seating depths. Keith shoots this rig prone off bipod, which is similar to the bipod shooting he does in the varmint fields. Keith explains key factors to consider when optimizing the .223 Rem cartridge in a varmint rig. Velocity readings are made with a LabRadar unit.

Keith Glasscock .223 Rem load development

Load Development for .308 Win Hunting Rifle

Keith Glasscock .223 Rem load development

In a second video, Keith shows the process for load development with a .308 Winchester hunting rifle. Here Keith uses a large X-type sandbag for a front support. Again, he was shooting a Remington 700 bolt-action rifle, this time with Barnes TSX solid copper bullets, PPU Brass, Federal 210m primers, and AR Comp powder. Keith said the Barnes bullets were excellent — he commented that these bullets were “match quality in terms of precision”. Keith achieved some very small three-shot groups with AR Comp and the TSX projectiles. Keith did note that point-of-impact shifted up significantly with increases in charge weight (see 6:20-7:10). With thinner-contour hunting barrels, this is not unexpected. But POI change should be observed carefully during load development, as you may need to adjust your zero after completing testing.


Keith Glasscock .223 Rem load development

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September 10th, 2025

Bullet Flight Video Shows Shock Wave + Bullet Base Drag

Science Accuracy Academy bullet video Schlieren movie shock wave capture

Ever wondered what the air around a moving supersonic bullet really looks like? Check out this video from the Bryan Litz Ballistics Facebook page. This is a Schlieren video* of a 6mm 109gr Berger LRHT bullet at about 2800 fps as fired from Francis Colon’s PRS rifle at the Applied Ballistics Lab.


Bryan Litz notes: “You can clearly see the compression (shock) wave at the front of the bullet. A compression wave is formed when the air has to move faster than the speed of sound to get out of the way, which is certainly the case for this bullet which is moving about 2.5 times the speed of sound (Mach 2.5).

That shock wave is the ‘snap’ you hear when bullets fly past you if/when you’re downrange. Also, compressing the air into a shockwave takes energy, and that energy comes directly out of the forward velocity of your bullet and gets converted into heat and noise as the shock wave forms and dissipates.

The turbulent wake at the base of the bullet shows where/how base drag applies. The third and smallest component of drag for a supersonic bullet is skin friction drag, which is a viscous boundary layer effect, and is the least visible in this image. So as you head to the range or the hunting stand, think about the absolute violence your bullets are committing in the atmosphere, before they even reach the target!”

Subscribe to the Science of Accuracy Academy for more precision rifle and long range shooting content. LINK: TheScienceofAccuracy.com.


* Schlieren imaging makes air flow features visible. SEE Schlieren Photography Wikipedia page.

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September 10th, 2025

How to Deal with Common Pistol Malfunctions — KEY Advice

pistol handguns semi-auto hang fire misfeed double feed stovepipe squib load

The Cheaper Than Dirt Shooter’s Log has a very helpful article for pistol shooters. This CTD article identifies five common malfunctions in semi-auto pistols, and explains how to deal with the five issues safely.

This can be very important — even life-saving. For example, with a hang fire, i.e. a round that does not fire immediately, it is vital to keep the gun pointed DOWN-RANGE. And with a squib load, which may have left a round inside the barrel, it is vital to UNLOAD and NOT take another shot! If you did, the gun could blow up in your hand when the second, full-charge bullet hits the trapped bullet.

The Five Topics Covered Are:

Misfeed (aka Tip-Up)
Double Feed

Stovepipe (Failure to Extract)
Misfire / Hangfire

Squib Load

1. Misfeed or Tip-Up: With any misfeed you should stop firing. With the muzzle pointed safely down-range, remove the magazine, then pull the slide back and remove the round that did not feed. Check the slide for dirt, debris, and check the round that did not feed. After re-inserting the magazine, make sure the mag is seated properly.

2. Double-Feed: This is a fairly common issue with some gun types with worn springs or cheap magazines. Again you want to remove the magazine. CTD states: “Remove the magazine and cycle the action until your double-fed rounds fall out — always keeping the muzzle pointed in a safe direction[.]”

3. Stove-Pipe: This occurs when the case of a fired round does not eject fully. There can be many causes — damaged extractor, low-pressure powder charge, dirty chamber, or greasy cartridge brass. In addition the issue is common with old, worn-out recoil springs. To avoid Stove-Pipes, replace the recoil spring every 4000 rounds, and make sure your chamber is clean and the extractor is not chipped or damaged.

4. Misfires and Hang-Fires: There are multiple causes for misfires (“click no bang”) and hang-fires (slow ignition). There can be a defective primer, the firing pin could be damaged, the powder many have been bad, or the case not filled properly. With a misfire, keep the gun pointed down-range at least one minute. If the case does not fire, eject it but leave it on the ground. With a hang-fire (delayed ignition after firing pin strike), keep the gun pointed down-range, then drop the magazine and eject the (new) unfired cartridge in the chamber and inspect the gun when completely empty.

5. Squib Load: A squib load is when the gun fires, but the actual case ignition is very light with little noise, smoke, or recoil. This can be because the case had a primer but no powder. Or it can be because the powder did not ignite. Squib loads can be very dangerous in rapid-fire situations. If you EVER get a squib load STOP immediately! Do NOT fire another round! This is because the squib may have left a bullet inside the barrel.

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September 10th, 2025

How to Properly Adjust Decapping Dies (and Not Damage Brass)

universal Decapping die sinclair lee redding

One of our Forum members complained that he wasn’t able to set his primers flush to the rim. He tried a variety of primer tools, yet no matter what he used, the primers still didn’t seat deep enough. He measured his primers, and they were the right thickness, but it seemed like his primer pockets just weren’t deep enough. He was mystified as to the cause of the problem.

Well, our friend Boyd Allen diagnosed the problem. It was the decapping rod. If the rod is adjusted too low (screwed in too far), the base of the full-diameter rod shaft (just above the pin) will contact the inside of the case. That shaft is steel whereas your case is brass, a softer, weaker metal. So, when you run the case up into the die, the shaft can actually stretch the base of the primer pocket outward. Most presses have enough leverage to do this. If you bell the base of the primer pocket outwards, you’ve essentially ruined your case, and there is no way a primer can seat correctly.

The fix is simple. Just make sure to adjust the decapping rod so that the base of the rod shaft does NOT bottom out on the inside of the case. The pin only needs to extend through the flash hole far enough to knock the primer out. The photo shows a Lyman Universal decapping die. But the same thing can happen with any die that has a decapping rod, such as bushing neck-sizing dies, and full-length sizing dies.

Universal decapping die

Whenever you use a die with a decapping pin for the first time, OR when you move the die to a different press, make sure to check the decapping rod length. And it’s a good idea, with full-length sizing dies, to always re-check the height setting when changing presses.

There are a variety of decapping dies currently on the market, with models available from LEE, Lyman, Hornady, RCBS, Redding, and Area 419 (at Brownells).

LEE Universal Decapping Die Costs Just $11.99
Speaking of decapping tools, Midsouth Shooters Supply sells the LEE Universal Decapping Die for just $11.99 (item 006-90292), a very good deal. There are many situations when you may want to remove primers from fired brass as a separate operation (prior to case sizing). For example, if your rifle brass is dirty, you may want to de-cap before sizing. Or, if you load on a progressive press, things will run much more smoothly if you decap your brass first, in a separate operation.

Lee universal decapping die

Decapping Dies for Cases with Smaller Flashholes

TAKE NOTE: Some Euro Small Flash Holes are spec’d at 1.5mm or 0.059″, and max out at about .062″, so these need a smaller die pin.

The low-cost LEE Universal Decapping Die will work with cartridges from 17 Fireball all the way up to big Magnums. However, NOTE that the decapping pin supplied with this Lee die is TOO LARGE for LAPUA 220 Russian, 6mmBR, 6.5×47, 6.5 Creedmoor, .308 Win (Palma) and Norma 6 PPC flash holes. Because the pin diameter is too large for these brass types, you must either turn down the pin, or decap with a different tool for cases with .059-.062″ flash-holes.

Brownells sells the impressive Area 419 Zero Universal Decapping Die. This features a spring-loaded decapping pin, with replaceable heads. The $50.00 die works with cases up to and including .338 Lapua length/diameter with no need for different inserts.

Redding makes a Universal Decapping Die with an optional smaller-diameter decapping rod for the smaller .059-.062″ flash holes found on the BR and PPC cases. The use of this die is explained in the video below:

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September 9th, 2025

Register Now for CMP Western Games in October 2025

cmp western games ben avery october 2025

If you live out west and enjoy rifle and/or pistol competition, then consider signing up for for the Civilian Marksmanship Program (CMP) 2025 Western Games. Featuring a wide variety of Rifle and Pistol matches, the annual event is set for October 16-23, 2025 at the Ben Avery Shooting Facility in Arizona. This big match is run very efficiently, with electronic targets eliminating pit duty. And new this year is a 1000-yard Long-Range Rifle Match.

CLICK HERE for Match Program | CLICK HERE to REGISTER

cmp western games ben avery october 2025

The Western CMP Games & CMP Cup Matches will feature Garand/Springfield/Vintage & Modern Military Matches, a Carbine Match, a Vintage Sniper Match and a Rifle Marksmanship 101/M16 Match (Introductory Marksmanship Class & Live Fire). The CMP Cup Matches include a CMP Mid-Range 3X600, a 2-Man Team Match, three days of CMP 800 Aggregate Matches and a CMP Service Rifle EIC Match. The Western Games will also include popular CMP vintage rifle events. All rifle matches will be held on the CMP’s outdoor eTargets — recently used at the 2025 National Matches at Camp Perry.

NEW FOR 2025: The CMP will be adding six 20-shot, 1000-yard Long Range matches held October 20-22. Competitors may fire in the Service Rifle, Match Rifle, F-Class, F T/R, AR Tactical or Palma Rifle categories.

RANGE & SQUADDING INFORMATION: All matches fired on the Highpower Range will be using the KTS Electronic Target System (no pit duty required). The CMP 80 Shot Matches, EIC Rifle Match, Carbine Match, Mid-Range 3X600 Match and Garand/Springfield/Vintage/Modern Military Matches will be pre-squadded.

2025 Western Games Notable Events:

Rifle Competitions
Garand, Springfield, Vintage & MM Matches
Carbine Match
Rifle Marksmanship 101/M16 MATCH
Rimfire Sporter Match
Mid-Range 3X600
1000-Yard LR Match
80 Shot Rifle
2-Person Rifle Team
EIC Service Rifle
Pistol Competitions
CMP Match Pistol 2700 (.22, .45, Centerfire)
Pistol Marksmanship 101/M17 MATCH
.22 Rimfire Pistol
EIC Service Pistol
EIC Service Revolver
Military & Police Service Pistol
1911 As-Issued Pistol Match

CLICK HERE to To see the Full Schedule of all Matches.

cmp western games ben avery 2025

CMP Western Games rimfire sporter Highpower high power rifle M1 Carbine Garand Sniper match

There Will Be Instruction as Well as Competition

The Western Games are open to any adult or junior with an interest in the sport – regardless of experience. Educational sessions will be held by trained instructors in the classroom and on the range. These are suitable for both beginners and more advanced individuals. This training will include Rifle/Pistol Marksmanship 101 training seminars.

Handgun Matches at Western Games

cmp western games ben avery october 2025
CMP Western Games pistol rimfire sporter Highpower high power rifle M1 Carbine Garand Sniper match

Handgun shooters can compete in four days of Pistol Matches including a Pistol Marksmanship 101/M9 Match (Introductory Marksmanship Class & Live Fire), CMP Match Pistol 2700, CMP .22 Rimfire Pistol EIC Match, CMP EIC Service Pistol Match, CMP Service Revolver EIC Match, Military & Police Service Pistol Match, and CMP 1911 As-Issued Pistol Match.

CMP Western Games INFO Page

Learn more about the October 2025 Western CMP Games via the CMP website. Access the full schedule and match program at https://thecmp.org/cmp-matches/western-cmp-highpower-cmp-games-matches.

Travel INFO for Ben Avery Shooting Facility

CMP Western Games pistol rimfire sporter Highpower high power rifle M1 Carbine Garand Sniper match

The Ben Avery Shooting Facility is located 25 miles north of Phoenix, AZ. It is one-half mile west of I-17 on the Carefree Highway (Exit 223). CLICK HERE for Ben Avery Camping/RV Information.

HOUSING: Competitors who plan to stay overnight near the Ben Avery Shooting Facility should stay north of the Phoenix area. There are numerous hotels, Air BnBs as well as Vacation Rentals (VRBO) in this area.


View Larger Map

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September 9th, 2025

Bullet Geometry Basics: Tangent, Secant, and Hybrid Ogives

secant tangent hybrid ogive Bryan Litz Applied ballistics 200X Berger Hybrid bullet, .308 30 Caliber

In discussions of ballistics, you’ll see references to “tangent”, “secant”, and “hybrid” bullet shapes. We know that, for many readers, these terms can be confusing. To add to the confusion, bullet makers don’t always identify their projectiles as secant or tangent designs. This article provides a basic explanation of tangent, secant, and hybrid ogive bullet designs, to help you understand the characteristics of these three basic bullet shapes.

Tangent vs. Secant vs. Hybrid
Most match bullets produced today use a tangent ogive profile, but the modern VLD-style bullets employ a secant profile. To further complicate matters, the latest generation of “Hybrid” projectiles from Berger Bullets feature a blended secant + tangent profile to combine the best qualities of both nose shapes. The secant section provides reduced drag, while the tangent section makes the bullet easier to tune, i.e. less sensitive to bullet seating depth position.

hybrid bullet

Berger Bullets ballistician Bryan Litz explains tangent and secant bullet ogive designs in a glossary section of his Applied Ballistics website, which we reprint below. Bryan then explains how tangent and secant profiles can be combined in a “hybrid” design.

How Bullet Ogive Curves are Defined
While the term “ogive” is often used to describe the particular point on the bullet where the curve reaches full bullet diameter, in fact the “ogive” properly refers to the entire curve of the bullet from the tip to the full-diameter straight section — the shank.

Understanding then, that the ogive is a curve, how is that curve described?

LITZ: The ogive of a bullet is usually characterized by the length of its radius. This radius is often given in calibers instead of inches. For example, an 8 ogive 6mm bullet has an ogive that is a segment of a circular arc with a radius of 8*.243 = 1.952”. A .30-caliber bullet with an 8 ogive will be proportionally the same as the 8 ogive 6mm bullet, but the actual radius will be 2.464” for the .30 caliber bullet.

For a given nose length, if an ogive is perfectly tangent, it will have a very specific radius. Any radius longer than that will cause the ogive to be secant. Secant ogives can range from very mild (short radius) to very aggressive (long radius). The drag of a secant ogive is minimized when its radius is twice as long as a tangent ogive radius. In other words, if a tangent ogive has an 8 caliber radius, then the longest practical secant ogive radius is 16 calibers long for a given nose length.”

Bryan Litz Explains Hybrid Design and Optimal Hybrid Seating Depths

Ogive Metrics and Rt/R Ratio
LITZ: There is a number that’s used to quantify how secant an ogive is. The metric is known as the Rt/R ratio and it’s the ratio of the tangent ogive radius to the actual ogive radius for a given bullet. In the above example, the 16 caliber ogive would have an Rt/R ratio of 0.5. The number 0.5 is therefore the lowest practical value for the Rt/R ratio, and represents the minimum drag ogive for a given length. An ogive that’s perfectly tangent will have an Rt/R ratio of 1.0. Most ogives are in between an Rt/R of 1.0 and 0.5. The dimensioned drawings at the end of my Applied Ballistics book provide the bullets ogive radius in calibers, as well as the Rt/R ratio. In short, the Rt/R ratio is simply a measure of how secant an ogive is. 1.0 is not secant at all, 0.5 is as secant as it gets.

Berger Hybrid bullet, .308 30 CaliberHybrid Bullet Design — Best of Both Worlds?
Bryan Litz has developed a number of modern “Hybrid” design bullets for Berger. The objective of Bryan’s design work has been to achieve a very low drag design that is also “not finicky”. Normal (non-hybrid) secant designs, such as the Berger 105gr VLD, deliver very impressive BC values, but the bullets can be sensitive to seating depth. Montana’s Tom Mousel has set world records with the Berger 105gr VLD in his 6mm Dasher, but he tells us “seating depth is critical to the best accuracy”. Tom says a mere .003″ seating depth change “makes a difference”. In an effort to produce more forgiving high-BC bullets, Bryan Litz developed the hybrid tangent/secant bullet shape.

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