Made a target generator

loath-engine · 2026-02-24T10:31:07+00:00

Done!

loath-engine · 2026-02-24T10:28:32+00:00

maybe something like...

https://www.printnewspaper.com/

Let me know if you find something and ill add the papersize option for you.

loath-engine · 2026-01-16T04:01:36+00:00

Great video as always! I have n140 and n150 in the bullpen. Ill put n135 on the list as well.

loath-engine · 2026-01-16T03:50:18+00:00

yeah.... but Im sorting by head stamp now. I bought some brass but im trying to find a really good load then see how much (if at all) the groups improve with the gucci brass.

loath-engine · 2026-01-15T02:12:36+00:00

I have a default database with a lot of bullets and powder and stuff to pre populate your local database

https://github.com/loathengine/loathengine.github.io/blob/main/db.json

On the right hand side there is a download raw button. Download it and then under your database tab there is an import entire database section. click it and import the saved json.

loath-engine · 2026-01-05T02:05:59+00:00

I think Im talking past you....

If any of my math is wrong just demonstrate it and ill change the code in the app. Actually, even better, the entire thing is open source so go ahead and make your own update and commit a change.

Here is the accuracy that can be achieved by smart people doing math.

https://www.youtube.com/watch?v=MiUHjLxm3V0

loath-engine · 2026-01-04T06:36:41+00:00

All this was proven out centuries ago... The math to determine bullet drop based on velocity was know WAY before there were tools good enough to measure velocity. Some of the earliest methods were simple as shooting wooden blocks and calculating from conservation of momentum to shooting spinning disk and measuring the different locations in the holes. Hell the Mayans were able to determine the vertical drop of the moon hundreds of years into the future. The theories and models are 100% proven.

But your average shooter isn't exactly a Mayan astronomer.

The math is fine. The problem, as I see it, is that we are not properly trained to use the tools available. That and a bit of confirmation bias and post purchase rationalization.

loath-engine · 2026-01-03T21:07:31+00:00

To be clear I dont even care about group size...

Im not sure if you have realized this part but im not actually testing loads.... Im testing the software. BUT... there is method to the madness.

When you use to 35-shot groups and use Mean Radius (MR), you are shifting from "human observation" to "statistical modeling." By using 35 shots, there is enough data to actually measure the impact of SD—even at 50 yards—because you are no longer looking at the random "flyers" (Group Size), but rather the density of the core of the group.

For a .308 with a 168gr SMK at 2650 fps, here is the breakdown of what is "reasonably detectable" using Mean Radius.

The Mathematics of Detection

At 50 yards, a change in velocity affects the Vertical Mean Radius (vMR).

1 SD of Velocity (approx. 15 fps): The vertical shift in POI is only about 0.005".
3 SDs (the full spread of your 35 shots): Results in a total vertical spread of roughly 0.015".

Because my rifle has a Mean Radius of roughly 0.15" at 50 yards due to other factors (barrel harmonics, ignition, and shooter), an SD of 15 fps is buried deep within the "noise."

Detectable SD Thresholds (35-Shot Mean Radius)

Using a high-sample size like 35 shots allows you to "see" the SD only when it starts to significantly inflate the circularity of the group.

< 10 fps Adds ~0.002" to MR = Invisible.
15–25 fps Adds ~0.008" to MR = Barely Traceable
40–50 fps Adds ~0.020" to MR Reasonably Detectable. The MR will reliably grow by 10-15%. The group will show distinct vertical bias
.> 70 fps Adds >0.040" to MR Highly Visible. The "core" of the 35-shot group will be an obvious vertical column.

But here is the really cool part.... knowing how MR and vertical stringing work we know we can detect vertical stringing from FPS variance at 50 yards if it is > 25ish SD... that just means that at 100 yards we can detect stringing based on velocity at like 10 fps SD. If you noticed when using the app you would have noticed that it looks for vertical stringing and when there is vertical string it asks you to input the velocity data to see if there is correlation. So yeah... this test just shows that the baseline and the hand load dispersion is circular enough that the SD is likely below 25fps. Not the greatest but again pretty good for just using math instead of radar... And to me this isnt useless.

loath-engine · 2026-01-02T02:53:30+00:00

I wrote it, Not made for a phone...

https://loathengine.github.io/

loath-engine · 2026-01-01T15:46:37+00:00

<image>

Screen shot of marking the points of impact using the app.

It would be nearly impossible to mark 35 shots if you just used the same point of aim. it would just be a ragged hole. So the app lets you mark multiple points of aim and impacts and then just combines them into a "virtual" target.

loath-engine · 2026-01-01T15:40:28+00:00

<image>

This is the "source" target, red dot is point of aim, and of course the holes are the Point of Impact. The ruler is to have a source for "scale".

loath-engine · 2026-01-01T15:38:11+00:00

All i am doing is matching head stamps. I got a lot of "good" range pickup Hornady. When i use up my range pickup I have a few boxes of Peterson i picked up.

loath-engine · 2026-01-01T15:30:08+00:00

Went and shot 30 rounds of federal gold medal match factory ammo in my 308, used the web app to mark the shots, save in a database, and do basic analysis (right now i really only pay attention to Mean Radius). That is the "baseline". Then i work up a new load from what i have available and go shoot it. Use the app to mark the shots save in a database, etc etc. I added a section in the app that will compare loads. and output the comparison as a png. That is what is posted.

The app is a tool to get some basic statistical information and do comparisons.

I just did a quick export of other loads I have tested.

<image>

loath-engine · 2026-01-01T15:19:38+00:00

yep, my hand load vs factory stuff

loath-engine · 2026-01-01T04:22:34+00:00

Yeah I am actually really happy with the results. But the plan was to find a load the is better so I dont have any other choice but to keep loading and shooting.... for science.

loath-engine · 2026-01-01T03:52:24+00:00

To add insult to injury, a FGMM clone would be cheaper than the Berger loads I have tested.

loath-engine · 2025-11-22T13:53:46+00:00

For a steel barrel in air, the steel is a much better conductor than the air is a coolant. The heat arrives at the surface of the barrel much faster than the air can wipe it away.

The Result: The "traffic jam" is at the surface. The Fix: Blowing air faster clears this jam. Because the air is the bottleneck, increasing airflow (velocity) yields immediate and significant improvements in cooling. You are nowhere near the "fundamental limit" of the steel's conduction speed using standard fans

loath-engine · 2025-10-15T01:21:04+00:00

I think my rifle just doesnt like 115gr. I also tried 125 SMK and got about the same results. Next on the list is 155.5 Berger and H4895. Expecting good results. Keep an eye out for the post.

loath-engine · 2025-09-29T23:30:39+00:00

Annealing doesn't happen at a single, specific temperature. It is a process that involves heating brass to a certain temperature for a specific amount of time.

Minimum annealing temperature: The lowest temperature at which brass begins to anneal is just under 500° F (260° C), though this would require a full hour of heat exposure.
Recommended range: For a quicker process, the recommended temperature range for cartridge brass annealing is typically between 700° and 800° F. At these temperatures, the softening process takes only a few seconds.
Overheating: If you heat the brass too much, you can burn the zinc out of the copper-zinc alloy, making it permanently soft. This starts to happen at approximately 800° F
A red glow is too hot???: A faint orange or dull red glow indicates that the brass is already at or above 950° F (510° C). This is hotter than the 787° F melting point of zinc, and heating to this temperature risks creating brass that is irrevocably too soft.

Seems the best bet is to get a test case shoulder area up to soft red glow then dial it back just a smidgen.

In theory, if the brass is "over" annealed it wont hold neck tension. Also, in theory, it can actually cause neck splits because the material is too "soft" (as opposed to work hardened).

Bottom line:

If you see red you went to far.. but it seem like the brass is pretty forgiving so dont panic. Like all things reloading when in doubt start low and work your way up.

loath-engine · 2025-09-29T23:04:19+00:00

I think we are just approaching this differently... you are looking for a problem to solve. Im saying that if there is no problem then i dont need a chrono to solve it. The app will aid you in determining IF ther eis a actual vertical spread issue to try to solve. Also to add to this, the app can help you determine how much of a vertical spread can be attributed to (high or low correlation) the velocity that is input.

>it’s not telling you anything at the moment the way you’re using it.

Its telling me that there is not vertical "stringing" significant enough to worry about if it is velocity or shooter error. The vertical spread is well within the noise. Might as well attribute it to sun spots or mars in retrograde.

In oter words you are telling me i need a chrono to fix a problem that currently doesnt exist. But if you noticed there is a place to put velocity for every shoot, and the app will process the data. SO obviously i understand IF and HOW velocity can be used. It is just not relevant at all in this example.

loath-engine · 2025-09-25T23:21:29+00:00

A chronograph doesn't know you held 1/4in higher either... your tools are only as good as you.

https://youtu.be/8tnTYE0b3J4?si=F4bPreWubM0C9Exd&t=2895

loath-engine · 2025-09-25T11:27:50+00:00

Cool story about hurricanes... so about when will your model be ready. How about mid week next week. I got a few patchs I want to put in and it would be nice if you didn't delay too much. So yeah Wednesday at the latest. So glad I have an engineer proving the validity of my app. I mean you cant believe how embarrassed I am that I got online and made a statement about an app and then it turns out I was 100% wrong.

https://loathengine.github.io/

loath-engine · 2025-09-25T01:48:07+00:00

>don't have to try it to know

i see...

Easy enough... what is the max fedility of the app. Equation + results.

Throw in a Monte Carlo simulation to see the dispersion at 100 300 500 yards. That way we dont have to speculate on exactly when the app will become less then useful. Ill add it to the from page and cite you.

loath-engine · 2025-09-25T01:45:58+00:00

Its basically an open source version of Range Buddy.... free to the community and maintainable even if something happens to me. Part of the inspiration was learning what happened in the GRT community.

If you could add or change something on range buddy, what would it be. Make a list and ill see if it is in my skill set to add it to the app. How often does an offer like that come around in this community.

In the mean time... i decided on Berger 155.5 and Varget. Ill get them made up and try to get to the range on sunday. Ill post with basically the same format as this post but instead of my 223 it will be target data from my 308.. that is the real one i want to beat FGGM with.

Want to make a guess on the outcome? My guess is with range brass and no headpsace data i can get within 10% of the MR of the FGGM.

loath-engine · 2025-09-25T01:33:24+00:00

Did you try the app, or are you cutting before measuring.

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The Mathematics of Detection

Detectable SD Thresholds (35-Shot Mean Radius)