new cartridge development

[Squibbler]

Pressure is what creates heat ( expanding gasses ) movement of molecules at a extreme rate pressure is what produces velocity. friction of the solid gas flow and the solid bullet gas flow compounded by surface temps from heat and expansion and contraction is what kills barrel life that's what its call erosion.

Exactly!

 

[Swamplord]

Hi,

That 70k pressure threshold that has been the choke hold of advancements is easier to break than people want to believe. To get past that pressure cap you must start with new cartridge design AND modern case manufacturing, not the cup/draw method and not attempting to "improve" a pre-existing cartridge design.

Sincerely,
Theis

Kind of where we are at with our 420 Blitzkrieg cartridge and a couple others, completely new concept in case design in order to bypass "pre-existing" issues when dealing with typical parent cases on the market, have done multiple wildcats that have potential but are held back by the ailments of parent brass,

Like Cheech said to Chong one time ..
" I'm sick up and fed with it man !"

 

[Sandow the Heretic]

Pressure is what creates heat ( expanding gasses ) movement of molecules at a extreme rate pressure is what produces velocity. friction of the solid gas flow and the solid bullet gas flow compounded by surface temps from heat and expansion and contraction is what kills barrel life that's what its call erosion.

Sort of... The DOD research on barrel erosion found that velocity of the gas flow was the most consequential factor. Heat matters too and cooler powders showed a decrease in erosion but only a few percent while dropping temps by about a quarter.

yield strength is a issue proper alloys and proper chamber design displacing pressures and compound structure design is a must yield in it self is not much of a factor if yield was a constant then battle ships could be paper thin. proper design of action, bolt, brass and chamber is critical.
,

Sure, thicker material is stronger. Doesn't mean that exceeding the yield strength isn't going to do bad things. You can still reflow surface metal into doughnuts and such. Are there stronger materials that we can use? Sure. Are you going to find someone that can or will make a barrel of out them? Probably not unless you can afford to sink millions in R&D.

-Alex

 

[THEIS]

Sort of... The DOD research on barrel erosion found that velocity of the gas flow was the most consequential factor. Heat matters too and cooler powders showed a decrease in erosion but only a few percent while dropping temps by about a quarter.

Hi,

But the caveat to those test were/are that the DOD uses and tested some of the largest bearing surface projectiles available per caliber/length/weight ratios.

If NDIA/DTIC/DOD would run that same test with more modern projectile designs, alloys and construction then we would see a decrease in erosion greater than decrease achieved from cooler propellants.
Add to that testing those modern projectiles with various coatings and barrel treatments and see what happens

This is one of those areas where NDIA/DTIC/DOD are behind the power curve in that the industry has things available that neither of those entities have tested and/or willing to test.

Sincerely,
Theis

 

[Sandow the Heretic]

Hi,

But the caveat to those test were/are that the DOD uses and tested some of the largest bearing surface projectiles available per caliber/length/weight ratios.

If NDIA/DTIC/DOD would run that same test with more modern projectile designs, alloys and construction then we would see a decrease in erosion greater than decrease achieved from cooler propellants.
Add to that testing those modern projectiles with various coatings and barrel treatments and see what happens

This is one of those areas where NDIA/DTIC/DOD are behind the power curve in that the industry has things available that neither of those entities have tested and/or willing to test.

Sincerely,
Theis

Actually this was mostly medium caliber stuff with a drive band so the actual bearing surface was quite low.

-Alex

 

[THEIS]

Hi,

Link?
What was the projectile design?
What was the projectile alloy?
What was barrel alloy?
What was rifling profile?
Etc Etc.......

Would be like saying drive bands put onto the old school 900gr and 1000gr .510 stainless steel projectiles that Gale Mc, Ken J and Scott Nye were messing with decades ago and expect it to decrease erosion on its own .

As lots of people have mentioned previously....the days of improving and advancing just 1 part of the puzzle has reached its' peak...advancements will only come now IF all the puzzle pieces are improved at same time.

Sincerely,
Theis

 

[Sandow the Heretic]

Hi,

Link?
What was the projectile design?
What was the projectile alloy?
What was barrel alloy?
What was rifling profile?
Etc Etc.......

Would be like saying drive bands put onto the old school 900gr and 1000gr .510 stainless steel projectiles that Rock Mc, Ken J and Scott Nye were messing with decades ago and expect it to decrease erosion on its own .

As lots of people have mentioned previously....the days of improving and advancing just 1 part of the puzzle has reached its' peak...advancements will only come now IF all the puzzle pieces are improved at same time.

Sincerely,
Theis

I'll try and dig it up when I get home. I dove a shitload of literature on the subject a few years ago and haven't touched it in a while. The testing was on 75mm canons though so it would have been a copper drive band.

Ah... the Zero Proflier lol. I have one of those in my collection that I dug out of the berm in Raton. Given the rust I'm going to go with what I remember being told the composition was, leaded steal alloy. Also closer to 700 grains. If they screwed with heavy stainless before moving on to brass I never heard about it. Don't suppose you have one of them do you? 1000 grain stainless bullet would have been stupidly long. Was that where the old 9.5 twist barrels came from?

-Alex

 

[THEIS]

Hi,

I do not have one of those stainless steel super heavies but Scott Nye may. They messed with those stainless steel heavies in an attempt to reduce the fouling issues of the Fat Mac suffered the standard copper and bronze projectiles, along with the 1000gr (IIRC) was in hopes to stop the "secondary" ignition of the Fat Mac.

I bet less than a dozen of those 9.5 twist were made. Do you have a shot out one that was passed down to you by the FCSA BOD by chance?

Sincerely,
Theis

 

[jasent]

I’d love to see some barrels made from better steel. H13 comes to mind. Sure it would be hard on tooling but barrel life would be significantly increased.

 

[THEIS]

I’d love to see some barrels made from better steel. H13 comes to mind. Sure it would be hard on tooling but barrel life would be significantly increased.

Hi,

That is like saying why do we not have vehicle tires that are good for 200k miles.....Because that industry is built on keeping the perception that the product is "consumable" and if that changes then so does profits

Maybe one day.......

I think we will see a modernized version of the micro-groove (I am thinking maybe a polygonal micro-groove) be tested by one of the custom barrel manufacturers before we see a change in alloys.

Sincerely,
Theis

 

[jasent]

Hi,

That is like saying why do we not have vehicle tires that are good for 200k miles.....Because that industry is built on keeping the perception that the product is "consumable" and if that changes then so does profits

Maybe one day.......

I think we will see a modernized version of the micro-groove (I am thinking maybe a polygonal micro-groove) be tested by one of the custom barrel manufacturers before we see a change in alloys.

Sincerely,
Theis

Your correct but a guy can dream. Maybe if alloy options where better we would be able to shoot more of the insane over bore cartridges and get more than a 1000 rds out of them. That would be nice.

300gr at 3700 would be a blast...... like I said I can dream lol

 

[Sandow the Heretic]

Hi,
I bet less than a dozen of those 9.5 twist were made. Do you have a shot out one that was passed down to you by the FCSA BOD by chance?

Sincerely,
Theis

Not sure on numbers. They were a match safety issue for a while since loads made for a 1:15 were way hot in a 1:9.5 but it hasn't come up in a decade or so. Sorta remember that it was an option in the State Arms.

We really don't pass hardware down within the BOD since everyone owns their own toys. I'd take a swag and say that Randy Dirks would have one of the old ones if anyone. Why though? Kenny will cut you a shiny new one for $320.

-Alex

 

[THEIS]

Hi,

Yea the safety issue was the shooters using jacketed projectiles in those twist rates when that was not the original intention of that twist rate.

Fast forward 10 years and it is considered common knowledge that jacketed projectiles cannot take the rpm of monos

Sincerely,
Theis

 

[Badger82]

View attachment 6993215

What exactly is a 375 Barrett improved? A 416 necked down to 375? Sorry I’m new to all this. That 420 blitz looks pretty awesome

 

[badassgunworks]

What exactly is a 375 Barrett improved? A 416 necked down to 375? Sorry I’m new to all this. That 420 blitz looks pretty awesome

its a 416 necked down to 375 then ackley improved

 

[Badger82]

its a 416 necked down to 375 then ackley improved[/

What’s the performance look like? I’d think it’s pretty impressive.

 

[badassgunworks]

not as good as you might think too much h20 volume and pressure limits of the bmg parent case inhibits performance.