Velocity Calculator

[borbal]

Well Jim, well known thermodynamic equations are used in the program, so it certainly is not a guess. Some factors are more important than others in an internal ballistics simulation like this, and bullet friction in the barrel is one of the least important.

As for powder energy, the program is tuned, if you like, for GOEX and Elephant powders. So if that is what you use, why don't you give the program a try....

 

[longcruise]

I think this is what the OP was looking for.

I just put this program together a few days ago and it needs some 'field testing', so I would appreciate it if you would feed in some numbers and see how it performs.

????????

 

[wganz]

Just buy a chronograph, then you know for sure what your velocities are.

I got a MagnetoSpeed that doesn't require screens just for this.

Linkage

 

[Jim in Wisconsin]

Borbal - I don't know what program you mean or how to access it. I don't think the performance of those powders is going to be at all consistent over time, and patch material and lube are going to be important. They certainly affect accuracy.

 

[longcruise]

I got a MagnetoSpeed that doesn't require screens just for this.

Linkage

How does that work with the ML gun?

 

[wganz]

How does that work with the ML gun?

Literally magnets. It holds itself to the barrel and it picks up the bullet going by.

 

[borbal]

Apologies. The word "this" contained a link to the website, which you can access by clicking on the word.

Here is the link..

https://www.p-max.uk/black_powder.htm

 

[Jim in Wisconsin]

Wow - that does look like a well done program! It certainly answers nkbj's original question. I wish I had a chronometer to check against it. Someone (you?) put a lot of effort and good work into making it. Thanks
In regards to the magnetospeed chronometer, it seems like having the sensor so close to all the "stuff" that flies out of a muzzleloader might be a problem.

 

[Loyalist Dave]

Well Jim, well known thermodynamic equations are used in the program, so it certainly is not a guess. Some factors are more important than others in an internal ballistics simulation like this, and bullet friction in the barrel is one of the least important.

As for powder energy, the program is tuned, if you like, for GOEX and Elephant powders. So if that is what you use, why don't you give the program a try....

A nifty program, but alas, Elephant and GOEX are no longer made, and while GOEX is due to return, until then we won't know.

I have some GOEX squirreled away for hunting purposes, so this program is fine for me, and in truth, I think for the vast majority of shooters, just getting results "in the ballpark" is sufficient.

For me that "ballpark" is being within 100 fps of the actual velocity..., and I write that because so many past tables/charts exist out there showing velocities for loads, but most are for 28" barrels and 42" barrels. For example the software has my load going 300 fps faster than the actual GOEX chart. But that chart is old and was flawed when first published, so....

I don't think the deer will react much different from a 1500 fps load that hits at 980 fps at 100 yards vs a 1800 fps load that hits at 1090 fps at that same distance.

I will enjoy comparing this with a chrono reading..., thanks for the link!

LD

 

[borbal]

but alas, Elephant and GOEX are no longer made,

Are you sure...?

https://goexpowder.com/products/

 

[longcruise]

Literally magnets. It holds itself to the barrel and it picks up the bullet going by.

Yes, I have seen them in use at the range. I was wondering how they would function with all the debris and the patch going by. I'm due for an upgrade but was not considering the magneto style over those concerns.

 

[longcruise]

Apologies. The word "this" contained a link to the website, which you can access by clicking on the word.

Here is the link..

https://www.p-max.uk/black_powder.htm

Thats interesting for sure. I don't see any reference to volume vs weight of powder. Is there any explanations of the functions anywhere?

I ran my hunting load through and it came up with a velocity that I am very doubtful of. However it will be a fun project to compare to a chronograph.

 

[borbal]

I don't see any reference to volume vs weight of powder.

A bulk density of 0.033 pounds per cubic inch is assumed. (Water is 0.0361 pounds per cubic inch).

I know a lot of people use volume measurements for the powder charge, and if there is enough demand I will put a charge volume as an alternative to charge weight. But for now, I am afraid you will have to put in the charge weight.

Is there any explanations of the functions anywhere?

There is some text below the entry form on the initial page. Other than that, I think it is pretty intuitive.

If you find something confusing or difficult to follow, do speak up and then the program can be improved.

 

[Loyalist Dave]

Are you sure...?

https://goexpowder.com/products/

I admire your faith, but Estes Energetics has not started production on any new GOEX since they bought the company, after the fire, in January of 2022. I know the website is up, but that means nothing....

Graf & Sons no GOEX of any kind

Powder Inc, was charging $35.00 a pound before adding fees, BUT...,

It's the same for all the large distributors, the ones GOEX will supply first, so...

LD

 

[longcruise]

The website does have a sign up feature where you can receive news from goex. Probably a good chance they will let you know when they are in production.

 

[Dale Allen Raby]

This is the result given for my .690 round ball out of a 12" barrel by the program under discussion. Doesn't look all that impressive on paper, but I'm not volunteering to be a test subject. What a .690 round ball does to aluminum soda cans and plastic gallon jugs is pretty impressive. Still, only 40% of the charge is burnt, so it give an illustration of how inefficient pistol-length barrels are.

Edit: Upon revisiting the calculator, I discovered an error that made a big difference; I had selected "whaling" for my "powder selection". Upon changing it to fffg, I got very different results, so I have edited the figures accordingly. My load is much more efficient now, at least at close range. This calculator is quite useful I think: P-Max black powder internal ballistics

Load density:​

100 %​

Pressure P-Max:​

9141 PSI​

Bullet travel to P-Max:​

0 in.​

Muzzle velocity:​

750 ft/sec.​

Muzzle energy:​

546 ft-lbs.​

Muzzle pressure:​

534 PSI​

Amount of powder burnt:​

95 %​

This is the result for my favorite .45 load, which uses a .40 caliber bullet inside an unmentionable. Not certain what I should have used for a bullet diameter, but I used .40. Someday I am going to buy a chronograph... or not.

Load density:​

100 %​

Pressure P-Max:​

20115 psi​

Bullet travel to P-Max:​

0.3 in.​

Muzzle velocity:​

1752 ft/sec.​

Muzzle energy:​

1227 ft-lbs.​

Muzzle pressure:​

1697 psi​

Amount of powder burnt:​

99 %​

 

[nkbj]

Apologies. The word "this" contained a link to the website, which you can access by clicking on the word.

Here is the link..

https://www.p-max.uk/black_powder.htm

Punched in the variables for the 90 grain load with Lyman #457124 and the calculated answer was within 25 feet per second of the velocity chronographed in 2013. That's purely awesome.
Thank you for linking a very nice resource.

 

[borbal]

Thank you for linking a very nice resource.

My pleasure. Glad it is working for you.