Among AccurateShooter’s most-visited web pages have been powder relative burn rate reference guides ranking powders from fastest to slowest. Here is the latest version of the Powder Burn Rate Table. Compiled by Hodgdon Powder Co., this Burn Rate Chart displays the relative burn rates of 176 different powders. Shown below is the latest table, released by Hodgdon in July 2024.
You’ll want to download this Powder Burn Rate Chart PDF. This 176-entry comparison table provides vital information for hand-loaders — with tested burn-rates. Note — this invaluable chart is not limited to Hodgdon and IMR propellants. This burn rate chart includes powders from eight major powder-makers: Accurate, Alliant, Hodgdon, IMR, Norma, Ramshot (Western), Vihtavuori, and Winchester.
This chart (July 2024 version) provides useful information for all hand-loaders. When doing load development, and testing one powder versus another, it’s generally wise to choose propellants that share the same relative burn rate, as least for starters.
NOTE: Hodgdon powders are red, IMR powders are yellow, Winchester powders are blue, Accurate powders are gray, and Ramshot powders are orange. Powders from Alliant, Norma, and Vihtavuori appear on the chart with white background. DOWNLOAD Burn Rate Chart HERE as PDF.
Photo 1: Three Near-Equal-Weight 7mm Bullets with Different Shapes
TECH TIP: Bullets of the same weight (and caliber) can generate very different pressure levels due to variances in Bearing Surface Length (BSL).
This article, from the USAMU Facebook Page, concerns reloading safety. In the relentless quest for more speed and flatter ballistics, some hand-loaders load way too hot, running charges that exceed safe pressure levels. Hint: If you need a mallet to open your bolt, chances are your load is too hot. Stay within safe margins — your equipment will last longer, and you won’t risk an injury caused by over-pressure. In this article, the USAMU explains that you need to account for bullet shape, diameter, and bearing surface when working up a load. Don’t assume that a load which is safe for one bullet will be safe for another even if both bullets are exactly the same weight.
How Bullet Profile and Bearing Surface Affect Pressure Levels
Today, we continue our handloading safety theme, focusing on not inadvertently exceeding the boundaries of known, safe data. Bullet manufacturers’ loading manuals often display three, four, or more similar-weight bullets grouped together with one set of load recipes. The manufacturer has tested these bullets and developed safe data for that group. However, seeing data in this format can tempt loaders — especially new ones — to think that ALL bullets of a given weight and caliber can interchangeably use the same load data. Actually, not so much.
The researchers ensure their data is safe with the bullet yielding the highest pressure. Thus, all others in that group should produce equal or less pressure, and they are safe using this data.
However, bullet designs include many variables such as different bearing surface lengths, hardness, and even slight variations in diameter. In fact, diameters can occasionally range up to 0.001″ by design. Thus, choosing untested bullets of the same weight and caliber, and using them with data not developed for them can yield excess pressures.
This is only one of the countless reasons not to begin at or very near the highest pressure loads during load development. Always begin at the starting load and look for pressure signs as one increases powder charges.
Bullet Bearing Surface and Pressure
Bullet bearing surface length (BSL) is often overlooked when considering maximum safe powder charges and pressures. In Photo 1, note the differences in the bullets’ appearance. All three are 7 mm, and their maximum weight difference is just five grains. Yet, the traditional round nose, flat base design on the left appears to have much more BSL than the sleeker match bullets. All things being equal, based on appearance, the RN/FB bullet seems likely to reach maximum pressure with significantly less powder than the other two designs.
TECH TIP: Bullets of the same weight (and caliber) can generate very different pressure levels due to variances in Bearing Surface Length (BSL).
Bullet 1 (L-R), the RN/FB, has a very slight taper and only reaches its full diameter (0.284 inch) very near the cannelure. This taper is often seen on similar bullets; it helps reduce pressures with good accuracy. The calculated BSL of Bullet 1 was ~0.324″. The BSL of Bullet 2, in the center, was ~0.430″, and Bullet 3’s was ~ 0.463″. Obviously, bullets can be visually deceiving as to BSL!
Some might be tempted to use a bullet ogive comparator (or two) to measure bullets’ true BSL for comparison’s sake. Unfortunately, comparators don’t typically measure maximum bullet diameter and this approach can be deluding.
Note: Due to time constraints, the writer used an approximate, direct measurement approach to assess the bullets’ different BSLs. While fairly repeatable, the results were far from ballistics engineer-grade. Still, they are adequate for this example.
Photo 2: The Perils of Measuring Bearing Surface Length with Comparators
In Photo 2, two 7mm comparators have been installed on a dial caliper in an attempt to measure BSL. Using this approach, the BSLs differed sharply from the original [measurements]. The comparator-measured Bullet 1 BSL was 0.694” vs. 0.324” (original), Bullet 2 was 0.601” (comparator) vs. 0.430” (original), and Bullet 3 (shown in Photo 2) was 0.602” (comparator) vs. 0.463” (original). [Editor’s comment — Note the very large difference for Bullet 1, masking the fact that the true full diameter on this bullet starts very far back. You can use comparators on calipers, but be aware that this method may give you deceptive reading — we’ve seen variances just by reversing the comparators on the calipers, because the comparators, typically, are not perfectly round, nor are they machined to precision tolerances.]
Thanks to the U.S. Army Marksmanship Unit for allowing the reprint of this article.
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.”
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.
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.
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.”
Q: What is the most popular gun book in the history of the planet?
A: That distinction goes to the Shooter’s Bible, which has sold over 7 MILLION copies since it was first published over 80 years ago.
Released in October 2025, the 117th Edition of this respected resource is better than ever. This latest Shooter’s Bible boasts 608 pages with over 270 color photos and more than 1000 black-and-white photos. The latest 117th Edition features many new firearms as well as new optics. This paperback book is now just $25.35 on Amazon, 15% off the $29.99 list price. A Kindle digital edition is also available for $21.99 on Amazon.
Published annually for more than eighty years, the Shooter’s Bible is one of the most comprehensive firearms reference guides in print. The publishers claim that “nearly every firearms manufacturer in the world” is included. The 117th Edition also contains new and/or enhanced sections on ammunition, optics, and accessories, along with updated handgun and rifle ballistic tables. There are also extensive charts of currently available hunting and match bullets for hand-loaders.
While many shooters are now using the internet to get reloading data and equipment specifications, the Shooter’s Bible remains a valuable resource with a great legacy. As one recent Shooter’s Bible purchaser explains: “While it’s true that much of the information contained in the Shooter’s Bible can be found on the Internet, there are many of us who would first rather relax in our easy chair and page through the book at our leisure. If you find an item that catches your fancy, you can then follow up by going to their Web site.”
Another buyer observed: “This [117th edition] is proof that, even with all the attacks on our 2nd Amendment right over the years, the industry has persevered and grown. I hope the day never comes when there will no longer be a reason to publish the Shooter’s Bible.”
The Shooter’s Bible contains a vast collection of firearms product information and descriptions. Hundreds of firearms are listed, complete with specifications and photos. Products from nearly all commercial gun makers on the planet are included.
More Great Gun Books From Shooter’s Bible Publishers
“The press is the heart of the handloading operation, also traditionally the most expensive single tool employed…” — Laurie Holland
British competitive shooter Laurie Holland has reviewed three popular, single-stage reloading presses for Target Shooter Magazine (targetshooter.co.uk). Laurie bolted up a Forster Co-Ax, RCBS Rock Chucker Supreme, and RCBS Summit to his reloading bench and put the three presses through their paces. These three machines are very different in design and operation. The venerable Rock Chucker is a classic heavy, cast-iron “O”- type press that offers lots of leverage for tough jobs. The smaller RCBS Summit press is an innovative “upside-down” design with a large center column and open front. It offers a small footprint and easy case access from the front. The Co-Ax is unique in many respects — dies slide in and out of the upper section which allows them to “float”. The cartridge case is held in the lower section by spring-loaded jaws rather than a conventional shell-holder.
If you are considering purchasing any one of these three presses, you should read Laurie’s article start to finish. He reviews the pros and cons of each press, after processing three different brands of brass on each machine. He discusses ergonomics, easy of use, press leverage, smoothness, priming function, and (most importantly), the ability to produce straight ammo with low run-out. The review includes interesting data on case-neck run-out (TIR) for RWS, Federal, and Norma 7x57mm brass.
Review Quick Highlights:
RCBS Rock Chucker Supreme
“My expectations of the antediluvian RCBS Rock Chucker Supreme’s performance weren’t over high to be honest as I mounted it in the place of the Summit. As soon as I sized the first of the stretched RWS cases though, I saw why this press has been such a long-running favorite. The workload was considerably reduced compared to the other two presses and doing 40-odd cases took no time at all with little sweat — it just eats hard-to-size brass.”
RCBS Summit Press
“Despite its massive build and long-stroke operating handle, [the Summit] took more sweat than I’d expected, even if it was somewhat less work than with the Co-Ax. Although the Summit is apparently massive, I noticed that the die platform would tilt fractionally under the heaviest strains[.] It is nevertheless a very pleasant press in use and bullet seating was a doddle — the few examples tried proving very concentric on checking them afterwards. The optional short handle would be valuable for this task.”
Forster Co-Ax
“[On the Co-Ax], the operating handle is above the machine, located centrally here [with] twin steel links at the top end of the press dropping down to the moving parts. The Co-Ax incorporates a number of novel features, principally its automatic and multi-case compatible shell-holder assembly with spring-loaded sliding jaws, very neat spent primer arrangements that allow hardly any gritty residues to escape and foul the moving parts and, the snap-in/out die fitment that allows rapid changes and also sees the die ‘float’ in relation to the case giving very concentric results. I own this press and it meets my handloading needs very well.”
Editor: Many new barrels will deliver higher velocities with the same load after 100-150 rounds through the bore. The exact reasons for this speed-up are not 100% certain, and velocity increases (if any) will vary from one barrel to the next. But this “speeding up” phenomenon is common, so be prepared if this happens with your next barrel. If you do experience a significant velocity increase you should probably re-tune your load AFTER the velocity stabilizes at the higher level.
From the Sierra Bullets Blog Article by Mark Walker, Sierra New Product Development Director
In a previous post, I discussed a couple of methods to tune a load to your barrel to help achieve the best accuracy possible. People most often work on load tuning if they get a new rifle or have a different barrel installed. In both instances, the barrel is new and has not been fired very much. According to most competitive shooters, this is the most accurate your barrel will ever be, so getting it tuned and shooting accurately is a priority.
The Speed Up Phenomenon After 100-150 Rounds
Even though after you work up a load and your new barrel is shooting great, a lot of shooters notice that at around 100 to 150 rounds their rifle may stop shooting as accurately. I had this happen to a rifle and I was confused as to why something that worked so well to begin with would all of a sudden quit shooting. I decided to break out the chronograph to do another load work up to see what was going on. To my surprise, the velocity had increased around 80 fps over the original velocity! After performing another ladder test and adjusting the seating depth, the rifle was once again shooting well.
There are several thoughts on why this may happen, however, you can rest assured that it does happen. One thought is that as the barrel breaks in, the tooling marks in the throat of the chamber smooth out and allow less resistance to the bullet as it exits the bore thereby increasing speed. Another idea is that the throat area starts to get a little rough which in turn causes more resistance which increases pressure and therefore more velocity. I’m sure there are some out there who have a better understanding as to why this happens, but it can definitely affect the accuracy of your rifle. So be aware and never be afraid to rework a load to keep your rifle in tune.
Experts Confirm That Barrel Speed-Up Is Common Two respected shooters have observed an increase in velocity with new barrels, typically after 100 rounds. Gunsmith and Hall-of-Fame benchrest shooter Thomas “Speedy” Gonzalez has documented barrel speed-up with testing. Moreover, Speedy’s bore-scope barrel inspections revealed a smoothing of the barrel lands. Jim See, a top PRS competitor, has encountered barrel speed-up many times. Accordingly, he re-tunes his load at 150 rounds.
“Alex Lipworth and I documented this phenomenon about four years ago and I have told all my customers about this. My son Mikee would shoot 100 rounds through all new barrels we planned on shooting before we would begin to do load development. We had a shooting snail that caught all the bullets set up in front of an indoor bench. We called it a wear-in process because upon careful examination of the bore when the ‘Speed Up’ takes place the cut-rifled bore resembles that more of a button-rifled barrels with the lands taking on more the softer look of a buttoned bore.” — Speedy Gonzalez
“Seen it [barrel velocity increase] too many times to count. All my match barrels get a ‘generic round’ loaded for them, which has worked well in barrels historically. After I hit 150 rounds I fine-tune the load and never look back, until the tube starts to slow down at it’s life end.” — Jim See
Do you have some ammo that got loaded incorrectly, perhaps with the wrong powder? Then you’ll want to disassemble the ammo for safety’s sake. You can use an impact puller to do this task, but if you have more than a dozen rounds or so, you may prefer to use a collet-style bullet puller. These work very quickly and positively, making quick work of big jobs. The efficiency of the collet-style puller is worth the investment if you frequently disassemble ammo. These devices retail for under $35.00 (collets sold separately). Normally, you’ll need a specific collet for each bullet diameter. But collets are not that costly, so this isn’t a big deal, particularly if you only load a few calibers, such as .223, 6mm, and .308.
Hornady and RCBS use different mechanisms to tighten the collet around the bullet. On the red lever Hornady Cam-Lock Bullet Puller, a lever-arm on the top of the bullet puller serves to tighten the collet around the bullet. Simply rotate the lever from the vertical to the horizontal position to grab the bullet. Lower the ram to remove the case. The bullet will drop out when you return the lever arm to the vertical position. This is demonstrated in the video below:
Hornady Cam-Lock Bullet Puller Demonstrated
Collet bullet-pullers resemble a loading die with a lever or handle on the top. They screw into a standard reloading press. Hornady and RCBS both make collet-style bullet pullers. They use the same basic principle — the device tightens a collet around the bullet, and then the bullet is separated from the case by lowering the press ram. NOTE: Collet pullers may leave small marks on your bullets, unlike impact (kinetic) pullers.*
Like the Hornady tool, the RCBS Bullet Puller employs a collet to grab the bullet. However, the RCBS tool tightens the collet in a different way. The head of the RCBS tool is threaded internally. By rotating the lever arm clockwise in a horizontal circle you squeeze the collet around the bullet. To remove the bullet, after lowering the press ram, simply spin the lever arm back in the opposite direction. The use of the RCBS tool is demonstrated in these two videos:
RCBS Collet Bullet Puller Demonstrated:
WARNING: When removing bullets from loaded cartridges, always make sure there are no obstructions or debris in your shell-holder or under the loaded round. NEVER engage a primer seating accessory on your press when working with loaded rounds. You can cause a round to discharge by contacting the primer! Also, we recommend you keep your head and torso away from the bullet puller tool at all times.
*By contrast, impact pullers rarely mark bullets, particularly if you put a little bit of foam or paper wadding in the closed end of your impact puller. When dismantling loaded rounds, powder kernels can get trapped in the wadding, so you should remove and replace the wadding before changing to cartridges loaded with a different powder type (assuming you intend to save the powder).
Bullet 1 (L-R), the RN/FB, has a very slight taper and only reaches its full diameter (0.284 inch) very near the cannelure. This taper is often seen on similar bullets; it helps reduce pressures with good accuracy. The calculated BSL of Bullet 1 was ~0.324″. The BSL of Bullet 2, in the center, was ~0.430″, and Bullet 3’s was ~ 0.463″. Obviously, bullets can be visually deceiving as to BSL!
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.
Review Quick Highlights:
Two respected shooters have observed an increase in velocity with new barrels, typically after 100 rounds. Gunsmith and Hall-of-Fame benchrest shooter Thomas “Speedy” Gonzalez has documented barrel speed-up with testing. Moreover, Speedy’s bore-scope barrel inspections revealed a smoothing of the barrel lands. Jim See, a top PRS competitor, has encountered barrel speed-up many times. Accordingly, he re-tunes his load at 150 rounds.
Like the Hornady tool, the 
