Aerospike 300 BLK 146 Lulu adventure begins

[dellet]

Glad you liked, I was concerned that I have sounded a little over the top that is why I referred to it as an academic spanking. I did get a little nasty with some points that an academic will see and in this case just gloss over as we are all wrong and he is right. Evidence his bullet's amazing ability is in the computer sims and not on the target where we are concerned about.

I received a patent years ago for an idea that worked out fantastically in the computer sims, but failed miserably when we tested and tested and retested ... The world is littered with physical ideas that worked out so well inside the computer but failed miserably outside, I claim ownership of more than one of those. We filed that patent before we could get our hands on the equipment to test it was not our intent to patent an idea that we knew failed in the field.

Having an idea and selling isn’t always about salemsnship. There is some timing involved. My wife’s grandfather patented the Spork. Couldn’t get any takers. Let the patent run out. Few years after that, I think it was an airline that picked it up or someone else presented it to them.

A swing and miss, next guy hits a home run on the same pitch.

 

[Just Say Moe]

Ha ha the algorithm has a sense of humor.....

 

[JLT]

Ha ha the algorithm has a sense of humor.....

View attachment 1575548

Maybe there's hope for AI after all!

"I don't care who you are . . . that's funny right there." - Larry the Cable Guy

 

[jimmymac]

I am grateful for this train wreck. Thanks. It gives me something to do while I recover from the China virus.

 

[Stumpy1]

Chill? Search my posts and see the responses right from the go. My existence apparently is offensive. I will not put up with it anymore.

And no, I've had more than a few PM me with kind words and offers to help. It is not the whole forum, just the really loud assholes.

Happy,
In my opinion, you would truly be well served to attend a few LR Benchrest or LR F-Class matches, heck even a Palma match and see what the top of the line competitors are up against in a match. Competition is fierce, and the winners are earning those top spots. I truly believe it would give you some perspective as to what our needs are. In two words, Accuracy AND Precision (at the same time), so all the details of bullet construction are indeed important.
If your design is successful, it has the potential to be a game changer. But in order to be successful, you need to pay attention to all the details that literally millions of rounds sent downrange have taught us are important. Many of the folks on this site have knowledge and insight that they would be way more than happy to share -if you will listen, try to understand, and try to apply to the next iteration of your bullet's design. Edison did NOT fail a bunch of times -he merely discovered a bunch of ways that wouldn't work -same here, I think, if you approach this with an open mind and perhaps a bit of respect to the folks that are producing some outstanding shooting results week-in and week-out.

So, the TL/DR version is; attend a few matches, watch, ask questions, listen, learn, and apply.

Really, we WANT you to be successful if your technology pans out.

Respectfully submitted,

Frank

 

[spike-55]

I just can't get past him measuring with RCBS units lol!!!! You would think he could invest a little of that GRANT money in some Starrett or Mitutoyo stuff that would give a little better degree of customer confidence lol!!!! Hell even us newbies and hacks got better stuff that that to measure with..... I gave that shit away as a pay it forward gift!!!!
stan

 

[HappyHellfire]

I just can't get past him measuring with RCBS units lol!!!! You would think he could invest a little of that GRANT money in some Starrett or Mitutoyo stuff that would give a little better degree of customer confidence lol!!!! Hell even us newbies and hacks got better stuff that that to measure with..... I gave that shit away as a pay it forward gift!!!!
stan

I knew I would catch shit for that! I just got the grant and will be using it to upgrade for sure. This research has been fully self-funded for years now. You get by with what you can.

I actually started out with an old balance scale.

 

[dellet]

Enough fooling around. You guys get serious or I’ll stop this car

@HappyHellfire, serious question here as I start developing loads.

You have said “normal stability calculators, drag curve equations” really don’t work for your bullet design.

There are generally two numbers generated that people use for choosing bullets generated by these off the shelf calculators,
1.5 stable at shorter yardage, punches a clean hole, may be accurate, will not realize full BC potential.

2.0 realizes full BC, less drop at distances ove 5-600 yards.

With that In mind, when you say your 146 Lulu needs 1/8, is that needed to punch a round hole in paper, or to realize full design potential?

Under 300 yards, maybe even 500, I would choose the more accurate twist, smallest group, vs needing to dial a few less clicks.

There is a big spread between no wobble, and maximum efficiency.

 

[wwbrown]

I knew I would catch shit for bring that! I just got the grant and will be using it to upgrade for sure. This research has been fully self-funded for years now. You get by with what you can.

I actually started out with an old balance scale.

A positive working relationship with a well-equipped experienced shooter that is local to you could help you decide what equipment would help your measurements. Go to a local rifle match that prizes accuracy and precision, and meet some of the potential customers. Try real hard to not up to everyone that you have a PhD, understand that academia and shooting ranges are different places. We show the world that we have advanced degrees in accuracy by the medals, trophies, and plaques that we have won. A PhD in ME does not get you any credibility at a shooting range if anything you are seen as a pointy head that is book smart but ...

Don't despair remember the mantra at many colleges "Lifetime Learning" you can learn to interface with shooters but you are going to have gain some skin, humility. Realize it ain't academia so the credentials you have spent your life developing have little value to the shooting community. Show that your bullets are the best thing since sliced bread and competitors start winning "stuff" with it and you will get instant credibility. But keep in mind that solids are not very popular in the high-accuracy shooting sports. But if your bullets are half as good as you say your behavior here will be overlooked as we all flock to your door to buy them.

 

[HappyHellfire]

Enough fooling around. You guys get serious or I’ll stop this car

@HappyHellfire, serious question here as I start developing loads.

You have said “normal stability calculators, drag curve equations” really don’t work for your bullet design.

There are generally two numbers generated that people use for choosing bullets generated by these off the shelf calculators,
1.5 stable at shorter yardage, punches a clean hole, may be accurate, will not realize full BC potential.

2.0 realizes full BC, less drop at distances ove 5-600 yards.

With that In mind, when you say your 146 Lulu needs 1/8, is that needed to punch a round hole in paper, or to realize full design potential?

Under 300 yards, maybe even 500, I would choose the more accurate twist, smallest group, vs needing to dial a few less clicks.

There is a big spread between no wobble, and maximum efficiency.

OK, back to work.

Yes, stability calculations are the same for my bullet as all other spinners. It is the ballistic trajectory calculators that don't work if they are based upon the BC method.

The short answer is "I don't know the actual Sg (gyroscopic stability number)". We design to get the number we want but to to actually measure it requires very expensive equipment and a good bit of math in what is called a spark range. Most bullets have a guess at Sg and if they fly a little wonky you go back and increase it.

Based upon my estimates, the 300 Blackout Aerospike has a Sg around 1.8 at 1800 ft/sec muzzle velocity with a 1:8 twist.

To get a bit more technical, we usually separate the drag coefficient into an expansion of:

Cd=Cd0+alpha^2*Cd_alpha

Alpha is the angle of attack. If it is close to zero (it never actually goes to zero) then the drag coefficient is equal to the zero yaw drag coefficient (Cd0). If I design a bullet to have a Cd of 0.3 at a muzzle velocity and I measure a Cd of 0.3, then the angle of attack must be very small.

 

[TTE]

I knew I would catch shit for that! I just got the grant and will be using it to upgrade for sure.

There are Chinese Starrett/Mitutoyo knock offs. You've been warned.

 

[dellet]

OK, back to work.

Yes, stability calculations are the same for my bullet as all other spinners. It is the ballistic trajectory calculators that don't work if they are based upon the BC method.

The short answer is "I don't know the actual Sg (gyroscopic stability number)". We design to get the number we want but to to actually measure it requires very expensive equipment and a good bit of math in what is called a spark range. Most bullets have a guess at Sg and if they fly a little wonky you go back and increase it.

Based upon my estimates, the 300 Blackout Aerospike has a Sg around 1.8 at 1800 ft/sec muzzle velocity with a 1:8 twist.

To get a bit more technical, we usually separate the drag coefficient into an expansion of:

Cd=Cd0+alpha^2*Cd_alpha

Alpha is the angle of attack. If it is close to zero (it never actually goes to zero) then the drag coefficient is equal to the zero yaw drag coefficient (Cd0). If I design a bullet to have a Cd of 0.3 at a muzzle velocity and I measure a Cd of 0.3, then the angle of attack must be very small.

What are you using for a bullet length, do you include the spike or not?

Not much of a difference, but interested to know

 

[HappyHellfire]

1.314" is the design length overall. If you look at the part number you can see all of the design details.

VK2.538_m0.1_b0.7_M1.6_308

Von Karman ogive with a length of 2.538 calibers
0.1 caliber meplat
bearing surface 0.7 calibers long
Aerospike base designed for Mach 1.6
308 caliber

 

[neckturner]

I have never asked for respect but I'll be damned if I put up with this disrespect any longer.

Here's a simple yet incredibly important business lesson for you: the customer may not be right, but they're never wrong. Everyone you're talking to on this forum is a potential customer.

Dellet is being measured and patient. If the critiques bother you that much, you'll need to grow a thicker skin if you want to get anywhere.

 

[Dave M.]

Having an idea and selling isn’t always about salemsnship. There is some timing involved. My wife’s grandfather patented the Spork. Couldn’t get any takers. Let the patent run out. Few years after that, I think it was an airline that picked it up or someone else presented it to them.

A swing and miss, next guy hits a home run on the same pitch.

My great grandfather invented the battery operated flashing light that used to be used on the top of the large orange traffic barrels. He received no money for the patent and his company put 2 other company men on the patent so they could claim majority ownership. They gave him a real shaft job.
Dave

 

[Dave M.]

OK, back to work.

Yes, stability calculations are the same for my bullet as all other spinners. It is the ballistic trajectory calculators that don't work if they are based upon the BC method.

The short answer is "I don't know the actual Sg (gyroscopic stability number)". We design to get the number we want but to to actually measure it requires very expensive equipment and a good bit of math in what is called a spark range. Most bullets have a guess at Sg and if they fly a little wonky you go back and increase it.

Based upon my estimates, the 300 Blackout Aerospike has a Sg around 1.8 at 1800 ft/sec muzzle velocity with a 1:8 twist.

To get a bit more technical, we usually separate the drag coefficient into an expansion of:

Cd=Cd0+alpha^2*Cd_alpha

Alpha is the angle of attack. If it is close to zero (it never actually goes to zero) then the drag coefficient is equal to the zero yaw drag coefficient (Cd0). If I design a bullet to have a Cd of 0.3 at a muzzle velocity and I measure a Cd of 0.3, then the angle of attack must be very small.

He just can’t resist throwing the coefficient of drag equation in the response to a question that doesn’t warrant the Cd explanation. We get it, you have degrees and a PhD.

 

[1911nut]

I want more formulas

 

[TTE]

I want more formulas

And less pics of small groups !

Oh wait ........... never mind

 

[dryhumor]

Do we have any test data yet? How they shoot?

 

[HappyHellfire]

View attachment 1575656
View attachment 1575657
View attachment 1575658

Do we have any test data yet? How they shoot?

Now your just teasing me! I love these images.

The top one is how yaw inducing devices work. I have a couple of students who will be working on designing one form me this year. The shockwaves bouncing off the wall and bullet (left picture) creates a strong pressure force on the base that increases the angle of attack. Not useful in practice but very useful if you want to measure the epicyclic motion with cameras or radar.

Notice the bottom images (CFD-Computational Fluid Dynamics) do not catch the swirling twirling turbulence behind the bullet. That is one of the reasons I have a difficult time using CFD with my bullets. The CFD doesn't catch the turbulence very well and my bullets work by reducing the turbulence.

Thus I'm mostly using live fire data to design my bullets.