Winchester’s new “Introduction to Ammunition — Ammo 101” is a four-part series including custom illustrations and information for four major ammunition categories: rifle, pistol, rimfire, and shotshell. The Ammo 101 series provides a detailed overview of centerfire rifle, centerfire pistol, rimfire, and shotshell ammunition, showcasing ammunition construction, components, calibers, and common usage. The Ammo 101 resource is free to download from Winchesters.mediaassets.com. Or, simply click one or more diagrams below. Each image will launch a large PDF which you can print or download.
TIP: Click Each Image for Full-Screen Printable PDF
Shown below are the first four ammunition information sheets prepared by Winchester. These show all the key components of cartridges and shotshells, and explain the functions. These diagrams are useful for training, and for persons getting started in reloading.
Ammo 101 Centerfire Rifle Cartridge Diagram (click for PDF)
Ammo 101 Rimfire Cartridge Diagram (click for printable PDF)
Ammo 101 Pistol Cartridge Diagram (click for printable PDF)
Ammo101 Shotshell Diagram (click for printable PDF)
About the Ammo 101 Series
The FREE Ammo 101 resources can help instructors nationwide who introduce new entrants to the shooting sports and hunting. Instructors can incorporate these resources into their training presentations, use them as handouts, or have them printed locally.
“The basics of ammunition… is what we want to deliver with the Ammo 101 series,” said Matt Campbell, Winchester V.P. of Sales & Marketing. “With millions of people across the United States starting their journey in the shooting sports as new firearm owners, providing easy-to-understand information on ammunition types is one way we can help educate our customers.”
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.
Brownells — Match Ammunition Sale, Major Brands, Many Types
⏺️ » Big savings on match ammo from Berger, Federal, Hornady and more
This week Brownells is running a major sale on top-tier Match Rifle Ammunition. You can save 10-25% on high-quality ammo for .223 Rem, 6mmGT, 6mm Creedmoor, 6.5 Creedmoor, .308 Win, .300 Win Mag, .30-06 Springfield and more. Brands on sale include Berger, Federal, Fiocchi, Hornady, and SIG Sauer. If you need factory ammo for an upcoming match or want to use it to test a new rifle, this is a good opportunity.
MidwayUSA — Major Athlon Optics Sale, Save up to 53%
⏺️ » Major discounts on wide selection of Athlon scopes and more
Athlon makes a variety of high-quality products, including rifle scopes, spotting scopes, thermal scopes, rangefinders, radar chronographs, and binoculars. Right now at MidwayUSA you can get discounts up to 53% on a large selection of quality Athlon products.
As an Amazon affiliate, this site can earn revenues through sales commissions.
With the catastrophic fires last year in California, many have wondered about hazards faced by gun owners in fire zones. This important video shows what really happens when loaded ammunition burns. You will probably be surprised. Contrary to Hollywood notions, the ammo doesn’t ignite in a massive explosion. Far from it… basically the rounds “cook off” one by one, and the bullets release at relatively low velocity. We’ve featured this SAAMI research project before, but it is worth reprising for those who have not yet seen the burn tests.
A few years back, SAAMI released an important video concerning ammo and fire. With professional fire-fighters standing by, over 400,000 rounds of ammo were incinerated in a series of eye-opening tests. If you haven’t had the chance to view this video yet, you should take the time to watch it now
The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) has produced an amazing 25-minute video that shows what actually happens to sporting ammunition involved in a fire. This video shows the results of serious tests conducted with the assistance of professional fire crews. We strongly recommend you watch this video, all the way through. It dispels many myths, while demonstrating what really happens when ammunition is burned, dropped, or crushed.
Watch SAAMI Ammunition Testing Video
Video Timeline
2:10 Impact Test (ignited outside firearm)
3:40 65-foot Drop Test
5:08 Bullet Impact (.308 Win firing)
7:55 Blasting Cap Attacks
9:55 Bulldozer and Forklift Tests
12:20 Boxed Ammo Bonfire
15:37 Bonfire without Packaging
17:21 Retail Store Simulation Burn
20:55 Truck Trailer Burn
Over 400,000 rounds of ammunition were used in the tests. Some of the footage is quite remarkable. Testers built a bonfire with 28,000 rounds of boxed ammo soaked in diesel fuel. Then the testers loaded five pallets of ammo (250,000 rounds) in the back of a semi-truck, and torched it all using wood and paper fire-starting materials doused with diesel fuel.
The video shows that, when ammo boxes are set on fire, and ammunition does discharge, the bullet normally exits at low speed and low pressure. SAAMI states: “Smokeless powders must be confined to propel a projectile at high velocity. When not in a firearm, projectile velocities are extremely low.” At distances of 10 meters, bullets launched from “cooked-off” ammo would not penetrate the normal “turn-out gear” worn by fire-fighters.
We are not suggesting you disregard the risks of ammo “cooking off” in a fire, but you will learn the realities of the situation by watching the video. There are some amazing demonstrations — including a simulated retail store fire with 115,000 rounds of ammo in boxes. As cartridges cook off, it sounds like a battery of machine-guns, but projectiles did not penetrate the “store” walls, or even two layers of sheet-rock. The fire crew puts out the “store fire” easily in under 20 seconds, just using water.
Additional Testing: Drop Test, Projectile Test, Crush Test, Blasting Cap Test
Drop Test
The video also offers interesting ammo-handling tests. Boxes of ammo were dropped from a height of 65 feet. Only a tiny fraction of the cartridges discharged, and there was no chain-fire. SAAMI concludes: “When dropped from extreme heights (65 feet), sporting ammunition is unlikely to ignite. If a cartridge ignites, it does not propagate.”
Rifle Fire Test
SAAMI’s testers even tried to blow up boxes of ammunition with rifle fire. Boxes of loaded ammo were shot with .308 Win rounds from 65 yards. The video includes fascinating slow-motion footage showing rounds penetrating boxes of rifle cartridges, pistol ammo, and shotgun shells. Individual cartridges that were penetrated were destroyed, but adjacent cartridges suffered little damage, other than some powder leakage. SAAMI observed: “Most of the ammunition did not ignite. When a cartridge did ignite, there was no chain reaction.”
Bulldozer Crush Test
The test team also did an amazing “crush-test” using a Bulldozer. First boxes of loaded ammo, then loose piles of ammo, were crushed under the treads of a Bulldozer. A handful of rounds fired off, but again there was no chain-fire, and no large explosion. SAAMI observed: “Even in the most extreme conditions of compression and friction, sporting ammunition is unlikely to ignite. [If it does ignite when crushed] it does not propagate.”
Blasting Cap Test
Perhaps most amazingly, the testers were not able to get ammunition to chain-fire (detonate all at once), even when using blasting caps affixed directly to live primers. In the SAAMI test, a blasting cap was placed on the primer of a round housed in a large box of ammo. One cartridge ignited but the rest of the boxed ammo was relatively undamaged and there was no propagation.
We are re-publishing this article at the request of Forum members who found the information very valuable. If you haven’t read this Safety Tip before, take a moment to learn how you can inspect your fired brass to determine if there may be a potential for case separation. A case separation can be dangerous, potentially causing serious injury.
On the highly-respected Riflemans’ Journal blog, created by our late, dear friend German Salazar*, there was an excellent article about Cartridge Case-Head Separation. In this important article, Salazar (aka GS Arizona) examined the causes of this serious problem and explained the ways you can inspect your brass to minimize the risk of a case-head separation. As cases get fired multiple times and then resized during reloading, the cases can stretch. Typically, there is a point in the lower section of the case where the case-walls thin out. This is your “danger zone” and you need to watch for tell-tale signs of weakening.
The photo below shows a case sectioned so that you can see where the case wall becomes thinner near the web. You can see a little arrow into the soot inside the case pointing to the thinned area. This case hadn’t split yet, but it most likely would do so after one or two more firings.
Paper Clip Hack for Detecting Problems
The article provided a great, easy tip for detecting potential problems. You can use a bent paper clip to detect potential case wall problems. Slide the paper clip inside your case to check for thin spots. GS Arizona explains: “This simple little tool (bent paper clip) will let you check the inside of cases before you reload them. The thin spot will be immediately apparent as you run the clip up the inside of the case. If you’re seeing a shiny line on the outside and the clip is really hitting a thin spot inside, it’s time to retire the case. If you do this every time you reload, on at least 15% of your cases, you’ll develop a good feel for what the thin spot feels like and how it gets worse as the case is reloaded more times. And if you’re loading the night before a match and feel pressured for time — don’t skip this step!”
* Sadly, German Salazar passed away unexpectedly on June 21, 2022 at age 62. German was a great inspiration to this site who helped guide the creation of the AccurateShooter Forum. A brilliant man, expert attorney, and top-tier marksman, German will be sorely missed in the shooting sports world.
What kind of accuracy do you think is possible from a rimfire benchrest rifle? If we said 0.44 MOA you might not be surprised, thinking this was at 50 yards. But how about 0.44 MOA accuracy at TWO HUNDRED yards. Now that’s impressive. Consider this — at 200 yards, a 10 mph crosswind will push that little 40gr bullet 15.3 inches. Here’s the story, which comes from the Land Down-Under, Australia.
A few seasons back, Australian John Lavaring shot a group at 200 yards that would make most centerfire shooters proud. The five-shot group, with all shots in the center 10-Ring, measured just 0.93 inches. That works out to 0.44 MOA at 200 — mighty impressive for a .22 LR. Recorded at a Rimfire Fly Shoot benchrest event in Canberra, Australia, this 200-yard target set two new Australian SSAA National records! John was using ELEY Tenex ammunition.
Congratulations to John Lavaring for a spectacular demonstration of how well a rimfire rig can shoot — even at 200 yards. We rarely shoot our .22 LR rifles past 50 meters. Maybe it’s time to start a Rimfire ELR series, with targets at 200 or even 300 yards. What do you think of the Rimfire ELR idea? Leave comments below.
Anschutz 54 Benchrest Rig
The rifle was a Anschutz model 54 Match in a custom benchrest stock. John’s record-setting rig features a barrel block, which you can see forward of the action. Scope is a Bausch & Lomb BR model. We don’t have the round count on Lavaring’s barrel, but good rimfire benchrest rifles can often get 10,000 rounds (or more) of accurate life.
Rimfire Ballistics at 200 Yards
Some folks may be wondering about .22 LR ballistics at 200 yards. Well, with a 25-yard zero, the 200-yard drop for John’s 40gr Tenex ammo is 54 inches, assuming 0.145 G1 BC and 1085 fps muzzle velocity per ELEY website. And at 200 yards, a 10 mph crosswind will push that little bullet 15.3 inches! We’re told the winds were pretty tricky when Lavary shot his record group. This makes his achievement all the more impressive — we have to admire John’s wind-reading ability.
This ELEY ammo has proven to be exceptionally accurate. Here is a short video showing TEN rounds of Tenex shot from a machine rest with target at 50 meters.
The shape of powder grains has a profound effect on the performance of the powder charge, as it concerns both pressure and velocity. There are multiple powder shapes including flake, ball, and extruded or “stick” (both solid and perforated).
So how does powder grain shape affect pressure and muzzle velocity?
In general, it can be said that powder that burns progressively achieves a desired muzzle velocity at lower maximum pressure than a powder that burns neutrally, not to mention a degressive powder. As grain size increases, the maximum pressure moves towards the muzzle, also increasing muzzle blast. Muzzle velocity and pressure can be adjusted by means of the amount of powder or loading density, i.e. the relationship between the powder mass and the volume available to it. As the loading density increases, maximum pressure grows.
All Vihtavuori reloading powders are of the cylindrical, single-perforated extruded stick type. The differences in burning rate between the powders depend on the size of the grain, the wall thickness of the cylinder, the surface coating and the composition. Cylindrical extruded powders can also have multi-perforated grains. The most common types are the 7- and 19-perforated varieties. A multi-perforated powder grain is naturally of a much larger size than one with a single perforation, and is typically used for large caliber ammunition.
Other types of powder grain shapes include sphere or ball, and flake. The ball grains are typically used in automatic firearms but also in rifles and handguns. The ball grain is less costly to produce, as it is not pressed into shape like cylindrical grains. Flake shaped grains are typically used in shotgun loadings.
Web thickness in gunpowder terminology means the minimum distance that the combustion zones can travel within the powder grain without encountering each other. In spherical powders, this distance is the diameter of the “ball”; in flake powder it is the thickness of the flake; and in multi-perforated extruded powders it is the minimum distance (i.e. wall thickness) between the perforations.
The burning rate of powder composed of grains without any perforations or surface treatment is related to the surface area of the grain available for burning at any given pressure level. The change in the surface area that is burning during combustion is described by a so-called form function. If the surface area increases, the form function does likewise and its behavior is termed progressive. If the form function decreases, its behavior is said to be degressive. If the flame area remains constant throughout the combustion process, we describe it as “neutral” behavior.
The cylindrical, perforated powders are progressive; the burning rate increases as the surface area increases, and the pressure builds up slower, increasing until it reaches its peak and then collapses. Flake and ball grains are degressive; the total powder surface area and pressure are at their peak at ignition, decreasing as the combustion progresses.
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.
Graf & Sons — Lapua Ammo Sale, Save 14-25%
⏺️ » Superb Lapua rifle ammunition with significant savings
Sometimes you need quality ammo but don’t want to spend the time loading and testing. Lapua Ammunition is a great option, using ultra-high-quality Lapua brass and bullets. With this Lapua ammo you can feel confident that on your next hunt you’ll have the best ammo possible when the shot is on the line. Right now Graf’s has Lapua ammo, in many popular cartridge types, on sale with 14-25% savings.
MidwayUSA — Major Athlon Optics Sale, Save up to 53%
⏺️ » Major discounts on wide selection of Athlon scopes and more
Athlon makes a variety of high-quality products, including rifle scopes, spotting scopes, thermal scopes, rangefinders, radar chronographs, and binoculars.
Right now at MidwayUSA you can get discounts up to 53% on a large selection of quality Athlon products. For example the Athlon Talos Spotting Scope is just $128.57, 41% off the regular price. And the Athlon Cronus ATS Thermal Scope is now $1199.99, a stunning 53% ($1400) savings off the regular price.
John Nosler lived 97 years, passing in 2010. During his long lifetime, John was an iconic figure in the shooting and hunting world. Considered a true pioneer in bullet and ammunition design, Nosler developed the famous Partition bullet in the 1940s. Born on April 4, 1913 in Brawley, California, John built his business from scratch. He founded his bullet company in 1948. He was considered to be one of the great innovators whose designs helped create the premium bullet category and influenced ammunition manufacturers worldwide.
Moose-Hunt Inspires Partition Bullet Design
While hunting in Canada, John experienced a bullet failure on the hide of a mud-caked bull moose. He then began developing a revolutionary new projectile, which he called the “Partition”, because of the barrier that separated the bullet into two sections. One year later, John and a friend traveled back to British Columbia with his new Partition bullets, which were designed to provide deep penetration and expansion. The men bagged two moose with two shots, and the rest is history.
NRA Golden Bullseye Pioneer Award
In recognition of his contribution to the shooting sports industry, John was the unanimous choice for the inaugural 2007 NRA Golden Bullseye Pioneer Award. The award was the highlight of a long and fruitful career. Even though he officially retired in 1988 when his son and daughter-in-law, Bob and Joan Nosler purchased the company, John still managed to come to the office on a daily basis until his health declined.
Today, John’s son Bob Nosler still presides over the company as president and CEO of Nosler, Inc., based in Bend, Oregon. Along with bullets, the company now produces cartridge brass, loaded ammunition, and hunting rifles.
To learn more about John Nosler and his innovative bullet designs, get your hands on Going Ballistic, a “Professional Memoir” told by John Nosler to outdoor writer Gary Lewis. CLICK HERE to find the Going Ballistic book on Amazon. It is offered in paperback for $19.99 or hard-cover for $53.76. There is also a $6.99 Kindle edition.
John Nosler remained an avid hunter and shooter even late in life. Gary Lewis recalled that, at age 92, John Nosler attended the opening of a new shooting range outside Bend, Oregon. Even in his nineties, Nosler managed to drill two shots inside nine inches at 1000 yards. John Nosler leaves a legacy that will benefit hunters and shooters’ nationwide. The John A. Nosler Endowment of The NRA Foundation, sponsors the NRA’s Basic Rifle Training Program which instructs novices in safe rifle handling.
Just last week hundreds of F-Class shooters competed at the 2026 Southwest Nationals in Phoenix, Arizona. The vast majority of F-TR shooters had rifles chambered for the .308 Winchester cartridge (7.62×51), but F-TR rules also allow the .223 Rem (5.56×45). There are some advantages to the smaller .223 Rem round — there’s notably less recoil, bullets and brass are significantly cheaper, and a lot less powder is required. For those who are considering campaigning a .223 Rem F-TR rifle, this story explains how an accurate .223 Rem load was developed. This load development was done by a father for his daughter who was getting started in F-Class competition.
Dad builds an F-TR Rifle for his Daughter and Develops Load
Jeremy Rowland decided to put together an F-TR rifle for his eldest daughter, who enjoys competitive shooting. For his daughter, Rowland chose the .223 Rem option because it has less recoil and components are less costly than the .308 Win. Here is Rowland’s account of how he developed a .223 Rem load. For more details (with data charts), read Jeremy’s FULL STORY on Sierra Bullets Blog.
Journey to Find a .223 Rem F-Class Load
by Jeremy Rowland, Reloading Podcast
My oldest daughter has been to several matches with me, and has even competed in several, using her .243. [A few seasons back] I decided, she would compete with a .223 Rem in F-TR. Looking for a good starter rifle, I settled on the Savage Axis Heavy Barrel since it has a 1:9″ twist. This would be a great little rifle for her to learn on. The rifle was shot unmodified, as it came from the factory. A Sinclair F-Class Bipod w/micro elevation adjustment was fitted to the front.
Next came finding the components I wanted to use for her match loads. After spending hours and hours running numbers on JBM stability calculator as well as in my iPhone Ballistic AE app, the 69 gr Sierra Tipped MatchKing® (TMK) looked really good. So that’s what I decided to go with. I jumped in head first and ordered a bulk pack of the Sierra 69 gr TMKs. I had settled on Hodgdon CFE 223 powder since it shows good velocity. I decided to go with once-fired Lake City brass with CCI BR4 primers.
Next came the testing. I decided to run a ladder test (one shot per charge from min to max looking for the accuracy node). The ladder test ranged from 23.5 grains to 25.6 grains, in 0.3 grain increments.
Bullet: 69 gr Sierra Tipped MatchKing®
Case: Lake City (mixed years, sorted by case capacity)
Primer:CCI BR4
Powder: Hodgdon CFE 223 (one round each from 23.5 to 25.6 grains)
Cartridge OAL: 2.378″
Base to Ogive: 1.933″ (.020″ off lands)
After his ladder test, Rowland settled on a load of 25.2 grains of Hodgdon CFE 223. He then fine-tuned his load with different seating depths: “I loaded up 5 rounds each at .020″ off lands, .015″ off lands, .010″ off lands, and .005″ off the lands. Here are the results from the best group for OAL/Ogive fine tuning. As you can see, I think I’ve found a winner in these 69 gr Sierra Tipped MatchKings.”
Need something for the walls of your “man cave” or reloading room? Looking for a great birthday gift for one of your shooting buddies? The creators of the Cartridge Comparison Guide offer a collection of wall posters showing ammunition types from 17 caliber rimfire cartridges all the way up to giant 35mm military rounds. ChamberIt.com currently offers 15 different large wall posters that display a huge variety of cartridge types. For example, the American Standard Poster (shown above) contains every standardized cartridge mass produced in the USA as of 2021. The cartridges are 100% to scale (life size). These posters feature full color images on high gloss / high quality 100-lb poster paper.
For example, the new MSR & AR Cartridges poster contains 60 cartridges that are commonly available in either a standard, customized, or proprietary MSR or AR platform with calibers from .17 Cal up to .500 Cal. This $14.92 poster displays 60 rifle cartridge types at true size (within 4/1000 of an inch).
MSR & AR Cartridges Poster Click to view large size poster.
Ammunition Performance Specifications Poster
There is also an interesting Ammo Performance Specs poster. This shows dozens of popular hunting cartridges with the velocity, energy, momentum and recoil for each cartridge displayed in a bar graph.
This shows the actual size of the Ammo Performance Poster as displayed on a wall.
The Sporting Arms and Ammunition Manufacturers’ Institute (
We are not suggesting you disregard the risks of ammo “cooking off” in a fire, but you will learn the realities of the situation by watching the video. There are some amazing demonstrations — including a simulated retail store fire with 115,000 rounds of ammo in boxes. As cartridges cook off, it sounds like a battery of machine-guns, but projectiles did not penetrate the “store” walls, or even two layers of sheet-rock. The fire crew puts out the “store fire” easily in under 20 seconds, just using water.
On the highly-respected Riflemans’ Journal blog, created by our late, dear friend German Salazar*, there was an excellent article about Cartridge Case-Head Separation. In this important article, Salazar (aka GS Arizona) examined the causes of this serious problem and explained the ways you can inspect your brass to minimize the risk of a case-head separation. As cases get fired multiple times and then resized during reloading, the cases can stretch. Typically, there is a point in the lower section of the case where the case-walls thin out. This is your “danger zone” and you need to watch for tell-tale signs of weakening.
Anschutz 54 Benchrest Rig
NRA Golden Bullseye Pioneer Award
To learn more about John Nosler and his innovative bullet designs, get your hands on Going Ballistic, a “Professional Memoir” told by John Nosler to outdoor writer Gary Lewis. 
