As precision shooters and reloaders, we’re constantly searching for new knowledge that can give us an edge. However, much of what we hear about ammunition is based on myths or outdated practices. If you’re serious about understanding how ammo really works, I’ve just uncovered a game-changing resource: Ammunition, Demystified by Jeff Siewert.
I’ll be referencing this book several times in upcoming articles, so I thought I’d go ahead and share a little about it – and the author behind it.
A Career Spanning Four Decades
Jeff Siewert is a ballistics engineer with 40 years of experience, working on virtually every caliber from .17 caliber all the way up to 8-inch howitzers! Jeff’s expertise spans bullets, propellants, cartridge case design, bullet-barrel interactions, manufacturing error analysis, and more.
Shortly after retiring, Jeff wrote a book to share the insight he gained throughout his career as an industry insider. He’s conducted research for some of the largest ammo companies in the world, and now, he’s sharing that hard-earned knowledge with the shooting community!
Demystifying Ammo: What You Need to Know
Siewert’s book is not your typical how-to guide for reloaders. Ammunition, Demystified pulls back the curtain on the complex science behind ammunition, challenging the common myths that many shooters still believe. It’s a “soft” technical document designed for both shooters who want to improve their understanding and engineers who are working with ammunition design and production. Although the book dives deep into the technical details, Siewert does an excellent job of making these concepts accessible to those who don’t work in the field every day.
For years, the reloading and shooting communities have been influenced by a mix of soft science and myths. That leads most reloaders to have a trial-and-error approach to bullets, primers, powders, and charge weights. We try a bunch of things in hopes of finding a magic recipe that sends all the bullets into one hole. As you might know from my Statistics for Shooters posts, as humans, we naturally tend to see patterns everywhere, but that can often lead to us seeing what we think are meaningful patterns in meaningless noise. Don’t know what I mean? Read the executive summary of those articles.
Siewert tackles this issue head-on by emphasizing the value of real scientific principles and how they should influence the way we approach ammunition performance. He also gives many practical tips for narrowing in on components and loads that are most likely to produce low dispersion (tiny groups) and consistent velocities.

I’ve likely read 20+ books on this subject, but I’ve never even thought about much of what Jeff presents in this book. There isn’t another resource like it. It is like the legendary book Rifle Accuracy Facts by Dr. Harold Vaughn, but with a focus on ammunition. I’ve seen used versions of Dr. Vaughn’s book sell for several hundred dollars – and this book could pack just as much value.
Why Should You Read This Book?
Whether you’re a serious competitor, long-range hunter, or simply a reloader who wants to dive deeper into the world of ammo, Ammunition, Demystified is packed with valuable insights that can help you improve your shooting and reloading practices. From understanding the intricacies of bullet-barrel interactions to discovering the true science of how ammunition behaves under pressure, this book offers a level of detail and depth that is unmatched by anything else available to the public.
Siewert’s career has been built on data and research, and this book reflects his commitment to uncovering the truth. If you’ve ever felt like something about your ammo knowledge was missing, this is the book to fill in those gaps.

In fact, I heard Jayden Quinlan, Senior Ballistician at Hornady, say he not only enjoyed reading Ammunition, Demystified – but Jayden said he finds himself pulling this book off the shelf about once a week to reference. When I heard that, it was enough to make me buy a copy. Over the past couple of weeks, I’ve had a hard time putting it down! I’m a little over halfway through it at this point, but I can wholeheartedly recommend it! I’d bet most of the pages so far have lots of highlights and notes written in the margins. 😉
Hornady regularly invites Jeff Siewert to join them on their more technical podcasts. Here is a recent example where they discuss gain twist barrels, which gives you a pretty good idea of who Jeff is and how he thinks.
The Bottom Line
There’s simply no other book like Ammunition, Demystified. It’s the definitive guide to changing ammo from being a mysterious black art to something we can understand. If you enjoy my content – then you’ll love this book!
If you’re still not convinced or just want to know a little more before you order the book, here is a podcast where Jeff talks about the book with the guys from Hornady:
To be clear, I’ve never met or even talked to Jeff – this is just a really good book! I bought the book out of pocket from Amazon. When I find something really helpful, I like sharing it with my readers – so that is what I’m doing here.
Jeff is also the author of Bulletology.com, so you can also visit that for more info.
Cal,
You are the data-driven guy, and I cannot thank you enough for the data-driven knowledge you share on your site.
Your words mean a lot, I am ordering this book order right now.
M. Shmaitelly
You’ll love it! I buy a ton of books like this, and read most of them … but in my opinion, this is one of those rare books that only comes around once every few years. Bryan Litz’s Applied Ballistics for Long-Range Shooting and Rifle Accuracy Facts by Dr. Harold Vaughn are the only two books that I think compare to it.
Jeff shares so much that is probably well established or “common knowledge” among manufacturers or professional ballisticians – but I bet 99% of the shooting community hasn’t heard most of it. Super interesting stuff! He also organizes it in a way that you can skip over “War Stories” if you’re looking to just get the meat of the book. Very pragmatic guy who can explain complex things in a way that’s easier to understand than most.
… like I said, you’ll love it! 😉 I don’t give blatant recommendations like this lightly – or often!
And thanks for the kind words about the content. I certainly try to make my content all data-driven and not simply anecdotal or based on opinion. The internet already has too much of that stuff!
Thanks,
Cal
Cal,
Just wanted to add one more thing, happy new year to you and your loved ones.
May 2025 be a great year for us all.
M Shmaitelly.
Thanks, Mahmoud. Same to you!
Does the book describe the interaction of the bullet with the case neck during initial release?
How about why when a cartridge load recipe, (powder, bullet, primer, brass prep), come together at a “sweet spot” that the velocity becomes more consistent?
Todd, the book describes the interaction of the bullet with the case neck and barrel in exhaustive detail. That is where the magic is! That is probably the most interesting part, because there is so much happening – and its not intuitive, because much of it is happening at way higher pressures than anything that most of us have any experience with. There are lots of things that it seems like happens all at once, but Jeff breaks down the order of operations step-by-step. Honestly, this stuff is literally rocket science, but Jeff makes it more approachable than any other resources I’ve ever found on the subject. He also has a comprehensive approach and goes into FAR more detail than any other resource I’ve come across.
I used to say that internal ballistics was just one of those things that we still don’t know a lot about. I thought it was still one of those frontiers we were exploring and trying to understand – but that isn’t quite true. There are people out there that understand it in excruciating detail … it’s just that the knowledge wasn’t making it to the general shooting community. It is a very specialized area of study, but I seriously feel like this book helped me understand it dramatically better than I thought was possible. That’s why I had to write the blog post to share it with others.
Jeff also talks extensively about propellant combustion and the characteristics you should consider to choose the “optimal” powder/load. I’ll share a little more on that in an upcoming article, but it’s all things that I hadn’t thought about before. Much of that plays into why some loads have more consistent velocities and group better than others. He also talks about primers and bullets. I’m not sure there is much in there about brass prep, at least not that I’ve seen so far. He talks about cartridge cases a lot and how they play into internal ballistics, but I don’t know how much is directly related to brass prep. Honestly, I’m page 192 of 396. While I’ve been reading it a lot lately, it is a dense book!
I hope that’s helpful!
Thanks,
Cal
Hi Cal
During the 2024 season I believe my shooting improved but not to the point I was totally satisfied. So I decided over the winter I was going to make several changes and your past articles lately have been helping with those changes.
So tonight I ordered the book you are recommending . I am hoping it will lead to some more changes to improve my reloading during 2025.
Thanks for the information Cal.
Paul Goggan
Sweet! I’m glad to hear that the timing of this little series of posts on reloading and ammunition worked out for you. Honestly, I wasn’t ever planning to do several articles in a row about reloading … but it just kind of developed as I’ve been publishing the last few “What The Pros Use” articles. I find it interesting, which is probably why I’ve written a little more about it. This book has certainly sparked more of that passion in me to dive deeper than I’ve gone before. I hope it does the same for you!
Thanks,
Cal
I decided to buy this book, it looks like it will be a good book to study carefully. In fact, I have read all of bryan lizt’s books, as well as the Rifle Accuracy Facts you recommended, and some math textbooks on statistics and probability. It took me a lot of time to understand the theory and math behind it, but it was worth and I learned a lot from those books.
Cal, can you give a list of recommended books? I am eager to read more good books like those . I would appreciate it.
Thanks a lot
Smith
Hey, Bryan. That’s a good question. I even thought about trying to compile a list of other books I’ve found helpful at the end of this post, but thought I’d leave it just being about the Ammunition Demystified book.
But, you made me start thinking. I bet I own 50+ books on some aspect of precision rifles, reloading, or rifle shooting. It’s become quite the library. And if I’m honest … many of them aren’t good. There are a few great ones … and many good ones. So, I’ll try to pass along my view of which I feel like I learned something significant from.
You literally named the books that would be at the top of my list of recommendations, but I spent a few hours tonight looking through my books and here is the list I came up with:
1. Applied Ballistics for Long-Range Shooting (4th Edition) by Bryan Litz. If I could only read one book on this list, I think I learned the most from this book.
2. Ammunition, Demystified by Jeff Siewert. I know … I’m kind of surprised to see this in the #2 spot, but after thinking about it … I stand by that decision. I’ve learned a ton about ammo and internal ballistics from this book that I’d never thought of before.
3. Rifle Accuracy Facts by Dr. Harold Vaughn. I almost put this 2nd, but I don’t think as much content is actionable as what I found in Ammunition Demystified. It is extremely interesting though. Still one of my favorite reads, and I get it out as a refresher occasionally.
4. Accuracy and Precision For Long Range Shooting by Bryan Litz. I love all of the Applied Ballistics books in their Modern Advancements in Long Range Shooting series, but I feel like Accuracy & Precision clarifies a ton of things that often hold shooters back – or at least the framework it presents helps you understand what you need to know or work on most.
5. Modern Advancements in Long-Range Shooting Volume II by Bryan Litz, Nick Vitalbo & Cal Zant. This is my favorite volume of Modern Advancements, not just because I got asked to be one of the authors and was able to contribute some of my research – but I find the reloading related chapters helpful and others, too. If I wasn’t in it, I’d still say it was my favorite of the 3 volumes so far.
6. Modern Advancements in Long-Range Shooting Volume III by Bryan Litz and Nick Vitalbo. Read my full review of this book.
7. Modern Advancements in Long-Range Shooting Volume I by Bryan Litz and Nick Vitalbo. I only have this 3rd because the other 2 were so good. This is a great one, too.
8. Top-Grade Ammo by Glen Zediker. I’ve read a few of Glen Zediker’s books, but this is my favorite. It was 1st printed in 2016, so it has a lot of modern advice on how to make good ammo, including quite a bit on reloading equipment and tools that is helpful. This is probably my top recommendation for an A to Z guide to reloading.
9. The Practical Guide to Reloading by Nathan Foster. I’ve read a few of Nathan’s books and I tend to really like how Nathan thinks about things, and his writing style. This 1st Edition was published in 2014, so it is also up to date on modern reloading methods, equipment, and tools. This is a close second to Glen’s Top-Grade Ammo book. I went back and forth on which one to put on top, because they are both good – and from a very different perspective. I’d say Glen mostly comes at it from a handloading for competition standpoint. Some of Glen’s content is about gas guns, although most of it is also relevant to bolt action rifles (which is what I care about most). Nathan on the other hand comes from a very practical, bolt-action rifle perspective. I feel like Nathan hits on a lot of little tips that aren’t covered in any other books I’ve seen.
10. Precision Shooting Reloading Guide. This was published by Precision Shooting Magazine, and I think it’s been out of print for a while … but this was a VERY good book on reloading. I feel like it was the only book like it for a long time. There were a lot of tips and tricks shared from some of the top precision rifleman of the time. I still think it’s a great book.
11. The Practical Guide to Bolt Action Rifle Accurizing & Maintenance by Nathan Foster.
12. Berger Reloading Manual, 1st Edition. There are several good articles in this (although they’re short).
13. Metallic Cartridge Handloading: Pursuit of the Perfect Cartridge by Mic McPherson.
14. The Book of Rifle Accuracy by Tony Boyer.
15. Extreme Rifle Accuracy by Mike Ratigan.
Honorable Mention: The Bullet’s Flight from Powder to Target: by Franklin Weston Mann. This book was originally published in 1909, so its a little outdated … but I still love looking through it. Here is the subtitle of the book: “The Internal and External Ballistics of Small Arms; a Study of Rifle Shooting with the Personal Element Excluded, Disclosing the Cause of the Error at Target”. Ha! Love it! 😉 That tells you a lot about the author right there. It is basically if Bryan Litz was born in the late 1800s. Some of the experiments that he did are so creative. While the author clearly didn’t have all the fancy tools we have today, he was still pursuing a data-driven method to learn about rifles and target shooting. It’s a classic. They also published a cool hardback version that is part of the “Firearms Classic Library.” If you don’t have one on your shelf, it’s a good addition.
I’m sure I’m forgetting one or two others. Honestly, I’m about to move a bookshelf from my office to my gun shop so I can keep all my books in one place. I literally am so excited about that, because they’re kind of spread over 3-4 different places right now. If I think of another one, I’ll come back and add it. This is at least a good start!
Thanks,
Cal
Wow, that’s perfect, I really appreciate it, Cal. I won’t have time to go out for drinks or play ball in the next few months because I’ll spend a pleasant reading time on the sofa with my e-reader.
Thanks again, and happy new year.
Bryan Smith
Merry Christmas Cal! And a Happy 2025!
Thanks, David! Same to you.
Thanks Cal. I picked up the Kindle version about a week and a half ago for research and agree completely. Great tool!
If any of your readers are interested, The other book, Rifle Accuracy, is available as a free download on archive. org. https://archive.org/details/RifleAccuracyFactsFullV1.0FirstFullScan_201705
Wow! That’s crazy that you came about it just about the time that I did. I was catching up on some of the more technical Hornady podcasts, and just happened to come across a few with Jeff on the show. When Jeff started sharing some of his modeling and charts on bullet exit states vs powder type … I thought, “Dang, this is REALLY interesting!” Then when Jayden Quinlan said he finds himself pulling Jeff’s book off the shelf to reference about once a week, I bought it within 5 minutes of hearing that.
Thanks for sharing your thoughts, and for the link to the Rifle Accuracy Facts PDF. I wish someone would reprint the book, but having a PDF version is helpful … maybe even more helpful at times.
Thanks,
Cal
Anything in here that will help the rimfire community?
Hey, Chris. Absolutely! I should have probably said more about that. This book isn’t just about rifle cartridges – but includes info about ammo for rimfire, shotguns, a little on medium caliber ammo (bigger than 50 BMG), and some other niche things. The majority of the content seems geared towards rifle shooters, and is relevant for both rimfire and centerfire shooters.
He has a whole section with the title “Notes on .22 Rimfire Bullets: Dispersion and Flight Behavior.” But there are also sections on barrel rifling, twist rates, bullet/barrel interaction, “The Myth of Mach 1 Turbulence” and a bunch of other things that seem applicable to a rimfire shooter.
Thanks,
Cal
Fantastic ty , just wanna say I really appreciate your articles. One of the few things I get in my e-mail that I open up right away because I know it’s going to be good.👍
Did you get your shooting tunnel set up? I do building automation and had some thoughts on the fan control and laminar flow.in the tunnel.
Hey, Chris. Thanks for letting me know you’re enjoying the content. I appreciate the encouragement.
I did get my tunnel finished out … or at least functionally complete. I’m sure I’ll always be trying to improve it in some way. For the air flow, I ended up hiring a HVAC engineer who specialized in small-arms indoor ranges to design the system. When I started, I hadn’t ever even heard the phrase “laminar flow” … but I sure understand it now! 😉 HVAC is complex, so I’m glad I hired a pro. That is something that could have real consequences if I got it wrong … like lead poisoning, which is often misdiagnosed and can be very serious. I feel like the ventilation system is working great. I had blood drawn a few months ago so we could test my lead levels, and everything looked normal.
Thanks,
Cal
This book is great!…….