So It's Back To First Principles

[khunter]

Hello Roger

Now you have shown me your diagram, I understand where you are coming from. Basically, you are using Google Earth. Now I realise you are referring to its source material as being high-level. But that is not the problem. The problem is using Google Earth itself as the ‘interface’ with the data, so to speak.

I initially tried using Google Earth myself, but realised that it is not accurate enough. It rounds up figures to the nearest foot. Also, the graphs it generates for various ground elevations are highly compressed and not that useful at all.

As a result of this, I discarded Google Earth and sought out a superior program. That is the one I mentioned in my previous message: randymajors. org. The source data for this program is the US Geological Survey. What makes this program superior to Google Earth, is that it produces ground elevation values to several places after the decimal point.

More than this though, the graphs that it generates are far more useful and detailed, and in addition, you can download a spreadsheet of all the ground elevation points for a given ground profile. This is what I showed in my previous image.

All that being said, let me show you what I get when I map the position of the bleachers onto Google Earth in like manner to my previous evaluation:

You can see that at the midpoint of the back of the bleachers, it gives 1335 feet elevation. If you move it towards corner point C, it then jumps to 1336 feet.

When using the randymajors. org site however, the values are far more specific, and not rounded crudely to the nearest foot. They are 1334.72 and 1335.68 feet.

I am more than satisfied that 1334.72 feet is the best value for the ground elevation of the bleachers, over either 1335 or 1336 feet.

I would advise you to test the program for yourself. Try running a ground profile of the perimeter of the bleachers and see what the elevation is at the midpoint of the back, and download the spreadsheet data.

Further to this, you also asked what values I have for Trump’s podium and also the ground height of building six that Crooks was on.

Using the randymajors. org site, I did a concentrated ground profile for the podium position of Trump, and averaged of all the elevation points (28) to get what I consider to be the best value:

1336.567679 feet.

This is seen from the following image:

For the building that Crooks was on, I did a ground profile for the entire perimeter of the building. This generated 203 elevation points. I took the average to determine the following value for the ground elevation of the building as a whole: 1334.564606 feet.

These 2 images show the analysis:

Data Values:

[pk2019]

@vegaspatriot

After using it on AGR grounds, he most likely put it back in his car when he went to get his backpack and rifle, unless it was in his backpack on the roof. He did have a second backpack in his trunk, per the evidence photo

But then I’ve yet to see a report of a range finder found with him, on the roof, in his backpack or in his car … only this remote control and these make ups of two explosive devices.

[vegaspatriot]

If we discount every bit of radio communications, interview statements, and after-action report entries regarding Nicol spotting Crooks using a rangefinder, I’ve wasted an entire month or more analyzing this event, and the evidence associated with it. If you discount one piece of evidence, you would have to discount every piece.

Trust me, I don’t put it past Nicol to lie, but the most solid piece of evidence of Nicol stating that he saw Crooks with a rangefinder (I carefully worded that just for you) was this radio communication:

5:42 pm - “’Just an FYI, we had a younger white male, long hair, lurking around the AGR building,’ a local countersniper said at 5:42 p.m., according to a time-stamped transcript of encrypted radio communications obtained by The Washington Post. ‘He was viewed with a range finder sighting the stage. … We lost sight of him.’” (Source: WP)

What is most compelling to me about that (alleged) sighting of Crooks with a rangefinder, is that it wasn’t until after that when Nicol finally decided he better start sharing photos he took of Crooks. In short, he realized then that Crooks was more than a “suspicious person,” he was a “person of interest.”

[phecksel (PhilH)]

@daniloraf

I went through manufacturer’s websites and got data for .223 and 5.56

My experience, mfg data is overly ambitious, and only shows up in perfect conditions. You also have to be wary, as many mfg measure velocity through a barrel longer than 16". I had contended that Crooks rifle looked longer than 16", some others disagreed with me, stating it is 16". I did an earlier post where I took a couple different ammo mfg and ran it through my 16" barrel, and across my chronograph that at lower speeds aligns well with a radar chronograph.

[daniloraf]

@phecksel

mfg data is overly ambitious

I hear you, but apart from running chrono on samples for 196 different cartridges, it sort of becomes ‘the art of the possible’. I’m a believer that, properly conducted, this little filtering exercise might reveal at least some reasonable candidates, or a reasonable interval.

@phecksel

You also have to be wary, as many mfg measure velocity through a barrel longer than 16".

I once got some 140-160 fps less from Magtech M193 on my 14.5" barrel as compared to their 20" mfg info. I’m still not sure how we could properly account for the barrel lenght differences on this find-the-bullet exercise from this spreadsheet. It took so long to gather the data that I still haven’t gone through the actual filtering criteria.

@phecksel

I did an earlier post

I remember. From your posts one can easily tell this is not your first barbecue around the topic. When you mentioned that too fast a spin can break the jacket, that we shouldn’t trust the info that it was exactly 5.56 and not .223,etc “not the first barbecue” all over it.

[roger-knight]

Dear KHunter,

Thank you for your detailed explanation. I will study it and try to use your method and come back to you later.

But maybe I forgot to give you this link to my important link, showing that I am not using Google Earth’s data (of which I agree are not accurate), I am using data coming from Land ID of which I import into Google Earth via KML file. Please have a look here:

@roger-knight

Download the KML file from Google drive in the link below and double click on the file. Google Earth should automatically launch, and the Trump rally boundary should be activated in red

Once you have download the KML file, simply double click it and Google Earth should launch automatically activating the heigh accuracy topographical Data.

One more time I would like to stress the fact that Gary in his video with his heigh accuracy drone, was able to find the exact some sea levels as with my method by using the KML file provided by Land ID. Using two different methods and finding the same result is a double check that confirms the sea levels that I am using are correct. One thing has to be mentioned however, Gary did not indicate the position of the stage, nor the bleachers, he only indicated building 6 and the fence, which was 100% in agreement with my measuring method. See my post here for verification:

@roger-knight

Many people get this wrong, so up to now everything looks legit

So, I suggest, I take time to try to do your method and you take time to do mine and we get back shortly to share our findings? Sounds like a deal?

[daniloraf]

@kincses-zsolt

What should we do? There are velocities at distance [0, 100, 200, 300] and maybe we should calculate at 150 yards?

Good question. And… yep, that would be it… for the Crooks scenario, we need the velocity of the bullet at 150ish yards.
One thing: to be honest, I’m not sure how manufacturers come up with the 0-100-200-300 data… on the muzzle I know they have a chronograph in front of the test barrel or the weapon, but I’m not sure if they get the 100-200-300 from formula or a chrono down range. Some manufacturers do a better job than others. Hornady, for instance, uses real rifles, instead of test barrels. Some don’t even have the data, just slap a muzzle velocity there after chrono and call it a day apparently. But I’m getting the feeling that Crooks was inserted in a place where he would choose better ammo. The range he went to apparently is where top shooters of that area go to, the store where he bought that ammo appears to be owned by a very good gunsmith, kind of the go-to guy, you know…? His shooting environment has all the traces of making one go for that top shelf ammo, learning how to tell the difference between ammo, etc.
As for the velocities, online ballistic calculators could calculate the velocity at 150 yards for all of those, but it’s very time consuming (and not fun enough, just boring to do lol).

I imagine we have to start like this: for a given range of crack-thump sounds… say 213 to 222 milliseconds, a distance of x, sound speed of y, what would the average speed have to be for those durations? This would give us 2 average velocities as an interval. Then, part 2, we calculate the velocity of each cartridge at the 150ish ft, like you said.

I defaulted to AI on approaches to estimate the velocities from the available data, it came back with two:
Approach 1: Linear Interpolation Between Data Points
Since you have velocities at 0 yards (muzzle), 100 yards, 200 yards, and 300 yards, you can perform linear interpolation between the closest values (100 yards and 200 yards) to estimate the velocity at 154.11 yards.
Interpolated Velocity=V100​+[(154.11-100) / (200-100​)]×(V200​−V100​)
### Approach 2: Estimate Average Deceleration
If you want a broader approach that doesn’t rely on interpolation, you can estimate an average deceleration based on the muzzle and 100-yard velocity. Then, project what speed the bullet would have at 154.11 yards and filter bullets accordingly.

Is there another way we could estimate the distance at 150ish?

Then we get the average for each cartrige, from muzzle to the velocity at 150ish feet. Then whatever’s not inside our previous interval, we can filter out. Then we can make qualitative eliminations also, say, filter out training ammo or some hard to find brands, etc… follow a trust-the-reporting-scenario and leave only 5.56 in boxes of 50, or follow the trust-noone and leave .223 and 5.56 as candidates.

At this point, just from filtering higher velocities and using qualitative assumptions, my top 5 candidates were these (let’s see if they change after the math)
1- Hornady 5.56 75 gr BTHP T2 TAP PRECISION (id 16)
2- Magtech 5.56 HPBT 77GR CANNELURED (id 124)
3- Hornady 5.56 62 gr TAP® BARRIER™ (id 13)
4- BackHills .223 Heavy Match HP 68gr (id 151)
5- CorBon .223 Urban Response JHP (id 55)

BTW, what exact distances are we looking at, @vt1 ? From Crooks, HighRoof, Vent, 2ndFloorWindow (which window, actually?) Do you have these distances in metric centimeters or imperial with decimals? I remember seeing these somewhere…

The durations of crack-thumps (or snicks-reports) from @greg_n are on this post here.

1-0.221
2-0.217
3-0.212
4-0.212
5-0.212
6-?
7-?
8-0.218

shorter: 0.212
longer: 0.221

On determining the average speed from the snick-report, Greg and @sonjax6 were writing about accounting or not for the distance from bullet to microphone here on this post
And @vt1 also wrote about it here

And @cohler wrote about it here

Do we already have the calculated average velocities from these snick-report durations?

[daniloraf]

This is what I got. All these are within the range of the average velocity, considering both the calculated values and also -4% on the calculated average of the cartridge at the distance of 154.11 yards, because of the, uh, ‘manufacturer optimism’ that @phecksel mentioned. On column ID I marked the remaining 11 candidates in green after I qualitatively eliminated the ones in red for various reasons (missing BC on website, barrel twist too low when there are better options, frangible, polymer, training ammo, rarer, too close to the edges of the calculated average velocities for snick-report, etc).

Then I marked my 4 best candidates with a green arrow on column ID. This is what I would choose. It’s within the math, if I got it right, and these have available data for Crooks to use on the ballistic calculator, three were tested with a rifle the same as his, and Hornady also makes a good ballistic calculator app. And this whole exercise just makes me believe he used the 100y zero… doesn’t strike me as someone who would be this picky about ammo and then use a lousy 25y zero.

1- Hornady 5.56 75 gr BTHP T2 TAP PRECISION (id 16)
2- Magtech 5.56 HPBT 77GR CANNELURED (id 124)
3 - Hornady 5.56 62 gr TAP® BARRIER (id 13)
4 - Hornady 5.56 70 gr CX™ TAP® BARRIER (14)

[pk2019]

@vegaspatriot

Trust me, I don’t put it past Nicol to lie, but the most solid piece of evidence of Nicol stating that he saw Crooks with a rangefinder (I carefully worded that just for you) was this radio communication:

VegasPatriot, please bear with me (and my French). I just wanted to point out a problem with the official story line. I hope that one day all these tatooed shooter types will be firmly questioned where they squirreled away that piece of evidence.

[vegaspatriot]

No worries. The evidence that is getting released is problematic, which is why I am doing my detailed analyses to make sense out of what really happened. Perhaps the worst example of problematic evidence is the Beaver County After-Action Report. Did you notice that the time stamped map for the 17:32 entry pertaining to the sighting of the rangefinder doesn’t show the location of Crooks when that sighting was made? They used the same map as the map used for the retaining wall sighting. What was added to the map was the location of the bike Nicol photographed.

[howdoiknowthisinfo (howdoiknowthisinfo.com)]

@khunter

The problem is using Google Earth itself as the ‘interface’ with the data, so to speak.

hello KHunter,

I’m so glad you brought this up…
I’ve been trying to make him understand this for over a month now, but he continues to ignore his erroneous use of Google Earth elevations and the remarkably odd elevation profiles it reports…
I hope he listens to you and takes your advice into consideration…

[roger-knight]

Hi KHunter,

I was able to try your Randymajors.com

I have to admit that it is a very good tool, better than Google Earth with my KML files.

The good thing though is that we are getting more or less the same sea level differences. The only major one being from the bleachers. I made a square in the exact place where the wheels are and I get two heights:

1335.68 and 1334.719, therefore I would be willing to take the average of 1335.2

Stage as per your findings: 1336.56

AGR building 6: 1334.56

I think we are sync with the following new Excel table? If you agree, I will back trace the bullet and start to make version 6 drawing.

[kincses-zsolt]

@vegaspatriot

Did you notice that the time stamped map for the 17:32 entry pertaining to the sighting of the rangefinder doesn’t show the location of Crooks when that sighting was made?

That would have been exacly my question.

If we think seriously, it could be a place he was able to do some triangle calculations. Not necessarily right angle (90 degree), the smart dude might use cosine theorem or something like that. But for simplicity, I would chose an ortogonal triangle.

[kincses-zsolt]

@daniloraf

we need the velocity of the bullet at 150ish yards.

There are some obvious mistakes in the data table.

22337 should be 2337 or 2237; 28874 should be 2874; 25373 is dunno.

Edit: 3 rows removed temporarily.

Choosen an arbitrary data row the coefficients shown.

[daniloraf]

@kincses-zsolt

There are some obvious mistakes in the data table.

Yep, sorry… typos… I caught those last night.
id - muzzle - 100 - 200 - 300
009 - 3050 - 2233 - 1571 - 1118
090 - 3240 - 2874 - 2536 - 2222
123 - 3085 - 2803 - 2537 - 2286

@kincses-zsolt

Choosen an arbitrary data row the coefficients shown.

Nice!

[cohler]

@daniloraf

Do we already have the calculated average velocities from these snick-report durations?

You can use my previously supplied Desmos plots and explanation to do this.

There’s no mystery here.

The speed of sound was 1152 fps.

If you have the (1) snik-report durations on a mic, and you know (2) the distance of the mic to the bullet at it’s point of closest approach to the mic, and you know (3) the distance from the shooter to the microphone.

THEN you can calculate the average velocity of the bullet with simple math.

If the shooter was Crooks on the roof, the numbers are:

(1) 220ms (1st shot) (MAIN MIC that Trump was speaking into)
(2) 1.07 ft
(3) 454 ft

The average velocity of the bullet was therefore 2622 fps.

You can use ballistics calculators to see what the implied muzzle velocity is for any particular brand and grain weight.

But it seems pretty clear to me, that given the barrel length, it was almost certainly a 70+ grain bullet.

[bumblebeeez]

What is all that info if the distance is shorter? What if the distance is 426.5 feet?

Thank you.

[cohler]

@bumblebeeez

What if the distance is 426.5 feet?

Speed of sound = 1152 fps
snik-report = 220 ms
mic-bullet = 1.07 ft
muzzle-to-mic = 426.5 ft
Average bullet velocity = 2857 fps

DESMOS CALCULATOR

[kincses-zsolt]

I will update the missing rows.

[daniloraf]

@bumblebeeez

What is all that info if the distance is shorter? What if the distance is 426.5 feet?

Essentially faster and lighter bullet candidates, ranging in weight from 53 to 69 grains, which have an average velocity at your distance (426.5) between 2700 and 2844 fps. Also needed to account for manufacturer error in measuring muzzle velocity,etc. If we can get some feedback on the approach to estimate the velocity at a given distance using the data from the manufacturers, and also come to an understanding about the importance of that bullet to microphone distance, it would be nice.
doing it quickly, it would narrow down the candidates from 196 to 56 possible cartridges, already considering a 4% margin on the manufacturer info. If that’s the vent distance, and assuming a vent shooter would also use .223/5.56, then I wouldn’t consider the round quantity per box in further filtering, but I would filter out ammo without a BC on the website. That said, whoever would be bold enough to attempt such a stunt, even if were possible, (shooting from that vent), he/she would probably just ignore website info and conduct a self-made ballistic test.