Range Report Just bought Litz's books

[coach4christ]

I just bought Litz's books Accuracy and Precision for Long Range Shooting: A Practical Guide for Riflemen and Applied Ballistics For Long-Range Shooting. All I can say is wow. There is a ton of info there. My head literally feels like it is going to explode. Has anyone else written anything on ballistics?

 

[Deleted member 10043]

It is a good book on external ballistics. And yes, there are a lot of books on the fundamentals of ballistics. I suggest you read more books on the topic before having an orgasm on this one. Litz did us a favor by putting it into a language we can understand but it is just a primer. He has a wealth of information on bullet specifications. That took a shitload of time and resources. Nevertheless, he makes off-handed comments with little or no scientific data to back it up such as the SMK 168 will tumble. Well, duh. All bullets tumble at some point. Even so, his explanation is there is no explanation because nobody, not even Einstein, has delved that deep into the science behind the claim. So, he sort of vacillates between the scientific method and unsubstantiated determinations. The Litz fanboys will come back and say their keyholed targets is proof enough but again they will leave out variables that they have yet to even think about. So, yeah. It's a good book. But there is more out there. Decades upon decades of it. Litz is a great person. He has helped answer several questions for me on this forum. He would be the first to tell you that his book is designed for the average shooter out there to understand.

 

[BryanLitz]

Thanks for your comments guys.

FYI,
The .30 cal 168 SMK tumbles due to dynamic instability. Specifically, the instability is caused by the 13 degree boat tail: too steep for the boundary layer to stay fully attached, too shallow for clean boundary layer separation off the bearing surface. The result is asymmetric boundary layer shedding which forces a positive feedback loop driving greater yaw angles, aka, dynamic instability.
-Bryan

 

[Heman]

Well stated Bryan.

 

[Deleted member 10043]

Well stated Bryan.

Really? Why don't you translate it for him because he is just rehashing what he wrote in the book?

Litz:

Why didn't McCoy figure this out when he studied and tested this bullet with all the resources of Aberdeen Proving Grounds available to him? His results provided to the military are easily googled.

 

[plh]

Thanks Brian from this quarter as well. As a would-be physicist who turned to the dark side of commerce, your published pursuits are welcomed and appreciated.
Pete

 

[BryanLitz]

Really? Why don't you translate it for him because he is just rehashing what he wrote in the book?

Litz:

Why didn't McCoy figure this out when he studied and tested this bullet with all the resources of Aberdeen Proving Grounds available to him? His results provided to the military are easily googled.

What exactly are you looking for? McCoys papers on this bullet describe the dynamic instability in aeroballistic terms; tables of numbers, 6-DOF simulations, etc. When someone asks 'why' the numbers are what they are, 'why' the dynamic instability, the physical answer is related to the boat tail as stated above.

I might be able to explain more clearly if I knew exactly what it is about this bullet that you'd like to understand better, which isn't covered in the google-able papers and the information above.

-Bryan

 

[Deleted member 10043]

Critiziing a bullet for acting normal is not scientific

I've ordered a copy of McCoys follow up in in the 1996 precision shooting annual. It includes the study of this bullet at long range as recommended in the Aberdeen study and probably suggests that the 168 SMK will tumble at long range. But I don't know why you picked this particular bullet to describe dynamic instability due to significant amounts of yaw at long range unless you are picking it out of particular study.

On the same page you describe that it is common knowledge bullets will become unstable at long range and tumble. Since the 168 SMK is not designed for long range I don't get using the 168 SMK to exemplify your point. I notice the Nosler 168 CC is almost an exact copy. Why would they use a 13 degree boat tail for dynamic instability performance? Same with the Hornady 168 Amax. So, I'm wondering why you are picking out a bullet designed for midrange competition and using it as an example for dynamic instability beyond 800 yards. I find it unnecessary to exemplify your point and damaging to the manufacturer. Especially, since the comments were not even needed to describe dynamic instability. Can you pick out any other bullet in your book that you specifically point out in this manner? You go on to explain that dynamic stability is difficult to predict because of the heavy dependence on aerodynamic properties that are difficult to calculate accurately, which are important as a bullet reaches transonic during which point "aerodynamic transients" are most dramatic. In other words, it is very difficult to explain but a bullet will tumble at some point during transonic. And yet you are spot on when it comes to the poor little 168 SMK? Specifically, the 168 SMK is no good past 800 yards unless it is subject to extremely high muzzle velocity. What is extremely high muzzle velocity 2700fps 2800fps? For some reason you end the critique on the 168 SMK with a sentence in italics about how most bullets designed for long range shooting don't have trouble with dynamic stability as long it maintains speeds above aprox. 1300fps. By coincidence the 168 SMK reaches this point at about 800 meters with a muzzle velocity of 2610fps. So, my point is are you criticizing this bullet or using it as an example to show how a normal bullet performs? Because you are coming across as criticizing the bullet and thus being misleading based on your own study and comments. The bullet is flying as advertised and by appearance you agree with that in the form of picking on it specifically. It doesn't make sense and it is totally out of character with the rest of your book.

 

[SavageStag]

^^^ Do you have a couple thousand 168's waiting to be loaded or what?

 

[Niles Coyote]

I can’t speak for Litz but when I got into LR shooting I had bought a couple thousand 168’s. Why??? Cause everything I had ever heard or read said they were great for long range shooting and the military/law enforcement shooters used it as such, or so I thought. It was not until my first day on the 900 and 1000y line that I was left scratching my head.

I came on here and learned I had heard and read bad info and switched to both 155’s and 175’s and suddenly I had the consistency back that I saw at closer distances.

I think it is good Litz puts that info in there as I am sure I am not the only one that has heard the stories of the great and mighty 168 smk popping tops in foreign lands or the printed word in novels of today. The people that will be reading this information from litz will also understand it’s a good bullet for supersonic velocity. As to why nosler closely copies the design, they want in on the smk’s success and there are just not enough of us LR shooters screaming to change the design when we can just switch to a different and better performing bullet. I was hoping that when nosler retooled (if they retooled) after the fire they might be the exception but that didn’t happen... why mess with a proven seller was the thought of the day, if there was even a thought. As for the Amax design, its bc seems to be high enough that the instability is not as much of a factor at 1000y so it is likely to go unnoticed to most that stop at that distance. But yes it sure would be nice if someone made a 165-168 grain bullet with the right features that could rival or best the 175smk all while not being plated in gold...

 

[BryanLitz]

Mr Culpeper,

I now see your concern, thanks for explaining.

The reason I 'singled out' the 168 SMK has a great deal to do with nilescoyote's comments. It's possibly the most well known and misunderstood bullet in all of long range shooting. Many people have the same problem with this bullet and want to know why. That's one reason why I singled it out.

Another reason is because the 168 SMK's dynamic instability is unique in that it doesn't just show up in the trans/subsonic range, but in supersonic as well. Coning angles begin growing with this bullet long before it slows to transonic speed, which is something that doesn't happen with most other bullets. The Nosler 168 CC, being a close copy, shares the same problem but how much commercial ammo is loaded with that bullet compared to the millions of rounds of FGMM with 168 SMK's that gets scooped up by eager first time LR shooters each year?

In summary, some bullets get special attention (for better or worse) due to their sheer popularity. If the bullet doesn't live up to what the shooter thought it was capable of, it requires a lot of explanation.

For example, I've seen a note to new shooters right in the match program of several LR competitions I've entered that 168 SMK's do not work at 1000 yards when fired from .308's. The organizers aren't going out of their way to single out that bullet just to be mean, but because so many new shooters try it and cause safety issues because they can't get on paper.
It's true that many bullets suffer lack of stability at transonic speed, but these bullets (168 SMK and Noslers copy of it) have an exaggerated problem because the unique dynamic instability begins in supersonic, limiting the effective range of the bullet dramatically more than most.

-Bryan

 

[waste_knot]

Thanks Brian,
That one comment was worth reading through all the BS on this entire site. And wouldn't you know it, I just ordered my first 500 round box of 168's. I'm still working on getting to 300 to 400 Yrds anyway.

 

[George Az]

Worth a read, just ordered the book as well. I put it down to stuff I couldn't figure out by myself and there is a lot of that kinda stuff in my life.

 

[peaceatwar]

Mr Culpeper,

I now see your concern, thanks for explaining.

The reason I 'singled out' the 168 SMK has a great deal to do with nilescoyote's comments. It's possibly the most well known and misunderstood bullet in all of long range shooting. Many people have the same problem with this bullet and want to know why. That's one reason why I singled it out.

Another reason is because the 168 SMK's dynamic instability is unique in that it doesn't just show up in the trans/subsonic range, but in supersonic as well. Coning angles begin growing with this bullet long before it slows to transonic speed, which is something that doesn't happen with most other bullets. The Nosler 168 CC, being a close copy, shares the same problem but how much commercial ammo is loaded with that bullet compared to the millions of rounds of FGMM with 168 SMK's that gets scooped up by eager first time LR shooters each year?

In summary, some bullets get special attention (for better or worse) due to their sheer popularity. If the bullet doesn't live up to what the shooter thought it was capable of, it requires a lot of explanation.

For example, I've seen a note to new shooters right in the match program of several LR competitions I've entered that 168 SMK's do not work at 1000 yards when fired from .308's. The organizers aren't going out of their way to single out that bullet just to be mean, but because so many new shooters try it and cause safety issues because they can't get on paper.
It's true that many bullets suffer lack of stability at transonic speed, but these bullets (168 SMK and Noslers copy of it) have an exaggerated problem because the unique dynamic instability begins in supersonic, limiting the effective range of the bullet dramatically more than most.

-Bryan

So some of this is straight over my head but most of it I am understanding. Do have a point at which you don't reccomend 168s? Is it 800m? Earlier? Reason I ask is I've been shooting 168's (FGMM) purely in matches out to 650 yards. I don't think I've experienced any tumbling but since I'm banging steel I guess I wouldn't know.

 

[Heman]

With no personal experience of shooting it but from listening to others the 180gr SMK (new one) will also exhibit the same charecteristics as the 168gr SMK and I am will to guess the 200gr SMK will also. Becasue they all share the same 13 degree boat tail and the same form factor. Although with their longer bearing surfaces it may help slighly but they will tumble out. It would be interesting if the 155,168, and 178 Amax bullets have teh same issue as their boat tail angle is also of 13 degrees, yet by being a different nose profile they may not have that same issue.

Personally I would like to know why Sierra decided to put a 13 degree boat tail on the 168 International (now 168gr SMK) when no other bullet they offered at the time had that. Did they not realize the consequences or was there a benefit for its intended use of 300m shooting.

 

[Deleted member 10043]

The bullet was designed for mid-range competition and started production over 50 years ago. Plenty of time for the shooting community to conjure up information about it; both fact and fiction. (1) It is a finicky bullet for good reason and that is to be accurate at mid-range. (2) It is a drag-strip bullet and should be used with a well built weapon w/1:12 barrel and within the bullet's limitations. Maximum velocity should not exceed 2700 fps; depending on the propellant used. Federal Gold Match uses this bullet at 2650 fps. Before that Federal produced it at 2600 fps. The increase in fps was probably due to people wanting to shoot out a little further. Thus, if a shooter is experiencing tumbling on paper within mid-range then perhaps there are more variables to look at then just using another bullet. I would hope there are no personalities before principles being applied to this bullet's reputation. Perhaps the next edition of the book will make clear that the intent is to educate the reader regarding misinformation that has accumulated over the years regarding this bullet and setting the record straight without giving the appearance of a conflict of interest. I'm not trying to be the bad guy here or a devil's advocate. I'm just paying attention to what is a well written book on the fundamentals of exterior ballistics and pointing at the elephant in the room. Just one sentence that is out of character is all it takes. Bryan, you have a wide audience of readers. Nevertheless, nobody can read what is between the lines. I appreciate you setting the record straight.

 

[Heman]

Exactly it was designed for 300m competition but what I'm saying is why the 13 degree boat tail? 175's are just as accurate and they don't have that degree of boat tail. Not picking on the bullet (not that it matters it is an inanimate object and doesn't have feelings). But just wondering why the parameters it has were chosen.

 

[Heman]

So some of this is straight over my head but most of it I am understanding. Do have a point at which you don't reccomend 168s? Is it 800m? Earlier? Reason I ask is I've been shooting 168's (FGMM) purely in matches out to 650 yards. I don't think I've experienced any tumbling but since I'm banging steel I guess I wouldn't know.

At typical loadings it would happen between 800-900yd line if your on a KD range. The Marines had a G4 load which was 44gr of IMR4895 and the 168 which shot quite well at 1000yds but beat the hell out of their M14's. so at your range you are shooting the 168 is still ok and you won't notice it.

 

[KYpatriot]

I thought the book was well written and is easily the best single source, comprehensive guide on external ballistics I have seen. It covers more detail than most LR shooters will need or even be able to make use of so I consider it one stop shopping for the vast majority of shooters out there on the subject. If someone want to see derivations of the equations they are looking for a math book, not a ballistics book. I haven't derived the equations, so I guess I am taking his word for it that they are correct. I am confident there is little risk in that. The book is a great resource on all the most common ballistics questions and problems.

Now for Bryan.....

Where is that 195gr 7mm bullet!!!!!!! Get off the forum and get on that production line LOL!!

 

[BryanLitz]

Now for Bryan.....

Where is that 195gr 7mm bullet!!!!!!! Get off the forum and get on that production line LOL!!

Thanks for the review.

Regarding new bullets...
Given the current demand and timelines for shipping orders, management has decided that our production resources are best spent filling orders than prototyping. As eager as I am to see some of these new bullets made, it's hard to disagree with the priority of filling orders. All this fear buying appears good for business on paper, but it has a crippling effect on progress.

Take care,
-Bryan

 

[bodywerks]

Just ordered the book. Looking forward to a good read.

Sent from my DROID BIONIC using Tapatalk 2

 

[ScottyS]

Science IS observation. It has been widely observed that certain bullets (we'll use the 168 SMK as an example) tumble at early transonic ranges in a wide variety of platforms. It has also been observed that other bullets (let's use the 175 SMK as an example) do not tumble at transonic ranges in many platforms. There is certainly a physical reason for this. Bryan makes a reasonable hypothesis based on knowledge of previous scientific observations. His reasons for doing so seemed perfectly clear to me - many new people are still stuck on using this bullet simply because it is a legacy product. Note that it is not in use by any competitive 1000 yard shooters in any game. Quantifying the effect and testing the hypothesis is something that could be done with enough resources, in a way that would satisfy a peer-review process. Unless one sets up the experiment and null hypothesis properly (i.e. the problem has been properly identified via experience or intuition in the first place), then nothing solving the problem is discovered no matter ho many resources are thrown at it. That's science.

Mr. Culpeper comes across as disgruntled or inflated. Picking and wide-ranging statements does not a peer-review make.

 

[bodywerks]

I am only on chapter 2 and have learned a thing or two and, most importantly, gained a new respect for the g7 BC. I have shot as far as 1340 yards and happy to just be able to hit my target. My new goal, after this book and lots of practice, is to make cold bore hits at 1k and beyond. Hell, at any range beyond 100 for that matter. Very informative book so far, and I'm only 30 pages in

Sent from my DROID BIONIC using Tapatalk 2

 

[Deleted member 10043]

"Mr. Culpeper comes across as disgruntled or inflated. Picking and wide-ranging statements does not a peer-review make. "

Lol. Subjective.


BTW, I haven't had time to read McCoy's follow up to the bullet, which will be objective. I'm thinking on copying it and posting somewhere on the net along with the original trials at Aberdeen. Since I haven't read it yet I have no idea if he confirmed all this way back in 95/96. But that won't matter. We want objective review is all.

 

[atiq]

bought both the books by bryan, and man there is tons of info for me to digest; The explanation of the angle firing is done superbly, couldn't be done simpler and better. From a background of LAW with NO mathematics for last 15 years or so.. Bryan's books with the simplified manner of explanation is a sweet addition to the info.
THANKS Bryan.

 

[mudpig]

I picked up the book a week ago and haven't put it down yet. Initially started with the appendix and working all the formulas and studying the BC tables, then went to the begining. On chapter 8 now, I think. The optics chapter, and I am very impressed with the book so far. For being a rocket scientist..Bryan has put the book into words and concepts that most of us can understand. I'm learning a great deal and can't wait to get into the practicle application of what I'm learning. I would love to see more BC testing/tables on some of the lighter hunting weight bullets (ie. 120gr-123gr 6.5mm bullets, 130gr-140gr .270, and 139gr-140gr 7mm). Keep up the great work Bryan!!!

 

[kraigWY]

I like McCoy, but it's a bit more technical and takes a bit more (for me) to digest. I have both of Litz's books, his are a bit easier for the layman to understand.

Hatcher is my favorite, mainly because he deals with the older vintage military stuff, which is where my true love lies.

 

[trickyric]

I just ordered Litz's book

 

[jerry1]

Litz's books are very informative. The time and expense of getting the data must have been very high. If I can learn something without reinventing the wheel I will take it gladly.

 

[Deleted member 10043]

McCoy's follow up on the 168 is on the net.

 

[FN in MT]

Applied Ballistics is having a $10 off sale on anything over $25

Enter the code "FBLike" and get the ten bucks off. Saves on shipping and takes a few bucks off the item.

Good until the 11th I think.