2031 FPS on air . Latest shot, 2162 FPS

[Gippeto]

Snortin right along Lloyd...well done.

Did notice you filled rather quick and fired right away...curious if you have means to measure the air temp within the reservoir....

Al

[Privateer]

I would love to see you Guys in chat on this just for a few hours if not less.
The instant interaction is fantastic.

[lloyd-ss]

Snortin right along Lloyd...well done.

Did notice you filled rather quick and fired right away...curious if you have means to measure the air temp within the reservoir....

Al

Al, no, I did not check the block for any heat when I filled it.  The block is 1 lb 10oz of aluminum so it will absorb and disperse the heat pretty quickly.  Next time I take a shot I will monitor a few of the technical details better.  I filled the gun quickly and took the shot quickly for 2 reasons: (1). I was videoing it and didn't want to waste  too much time and then have to edit the video which always raises questions about the validity of the video, and 2.,  This is a bare-bones prototype and I didn't want to take too much time and give the projectile o-ring a chance to extrude and leak.
More careful shots are planned and ideas on what seriously "needs" to be monitored are welcome.
Lloyd

[AmBraCol]

Gotta love the "can do" spirit on this forum.    Congratulations, Lloyd!  Now, what'll it do with a lead projectile?   

[MicErs]

Cool!
I bet diablos wouldn't like that speed at all.

Hard to say. They've never been shot that fast before, LOL. 

Very impressive!  Well done!  I recall a Lyman black powder manual that showed round balls made from soft lead start to flatten out due to air pressure alone after they get above 1800 or 1900 FPS.  For pure lead, 1750 is about as fast as you want to push it and by then leading has already become a problem.  A well patched ball doesn't lead a barrel.  I should add, I've heard that a round ball is the lightest projectile you can fit in a bore and a patch really is just a sabot.  James Fenimore Cooper makes reference to using leather as a patching material.

[rsterne]

If there was a way to allow the pressure to come up before the round ball moved, a patched aluminum ball might be as light as you could go with sufficient strength.... but that would need the complication of a burst disc, and the uncertainty of how much energy it would eat up....

Bob

[I_like_Irons]

Another idea for a projectile would be a sabot propelled airgun dart.

[rsterne]

Holding the sabot against the full pressure before firing is the problem I see.... Perhaps with such a long barrel this is less important, I don't know.... We are working with a total projectile weight (.278 cal) of just 9 grains, so achieving higher velocity would require less weight than that....

Bob

[Jeff m]

Great job Lloyd ! This is where advances are made in this sport , with people willing to do the work to test the limits of what can de done!

[Back_Roads]

 Yeah lets just call this a science project
Very very interesting one though !

[strever]

very impressive Lloyd
job well done

[lloyd-ss]

very impressive Lloyd
job well done

Dick,
Thank you.  Still more to be done.  Will be reporting in the coming weeks.
Lloyd

[62hotrod]

  Lloyd you, Rstern and couple of the other Brainiac's(hope I spelled it right) amaze me. You guy's come up with some of the best idea's and freely share them with the community. Well done and well played. I really wish I'd paid more attention in school now, but those pretty girls had my attention.............

[lloyd-ss]

I've been working on this more (obsessed ??     ) and the progress has been a struggle.  There might not be a lot of practical application to what I am doing but it shows what might become commonplace in the future.  Years ago, airguns only shot 500fps, and that is ancient history now.

This is a special 46" long smooth bore .278 barrel and special breechblock that holds the projectile until full pressure builds up and then instantaneously releases the projectile.  2162 fps this time    .  Yes, I realize that pellets don't fly well at high velocity, but this would be for lead bullets.  And I realize that 2162 is too high of a velocity for lead bullets (supposedly) because the rifling will strip off the bullet, but this is not a powder burner with hot gas working at 30,000 psi.  The acceleration is much slower and who knows, the rifling in the lead just might hold up.

I didn't make a video of this shot.  For anyone interested in the boring details    , there is a long thread going in the R&D Gate inside the Machine Shop Gate. 

Here are a few pics I took of the 7075 aluminum alloy "pellet" that it is shooting, and a pic of the chrony after the shot.  I recovered the pellet by shooting it into a tube about 18" long, stuffed full with plastic grocery bags, and positioned behind the chrony.  You can see some of the plastic bags hanging out of the tube in the pic of the chrony.  Good, clean, fun. Definitely keeping me off the streets.
Lloyd

[MichaelM]

WOW!!!!!!!!!!

[lloyd-ss]

WOW!!!!!!!!!!

Michael, I plan on bringing this to the FunShoot in May.  I am looking for someone to catch the bullets, kind of along the lines of the guy in this video 


Know anyone who might be up for the challenge? 
Thanks,
Lloyd

[match]

And I realize that 2162 is too high of a velocity for lead bullets (supposedly) because the rifling will strip off the bullet, ...

That depends on the alloy used and a few other things.

I have shot cast lead at 2600 fps in a 30-06 without issues.

[nielsenammo]

And I realize that 2162 is too high of a velocity for lead bullets (supposedly) because the rifling will strip off the bullet, ...

That depends on the alloy used and a few other things.

I have shot cast lead at 2600 fps in a 30-06 without issues.

You can also coat the bullets with HighTek coating.  It works in powder burners with the hot gas and you need no gas check and no lube in the lube grooves.  I use it on my personal slugs to prevent leading and I have to clean my barrel a lot less.  Would work great if it evolves where these higher velocities are a reality.

[lloyd-ss]

And I realize that 2162 is too high of a velocity for lead bullets (supposedly) because the rifling will strip off the bullet, ...

That depends on the alloy used and a few other things.

I have shot cast lead at 2600 fps in a 30-06 without issues.

John,
Thanks for letting me know.  You hear so many conflicting stories, it is always a pleasure to hear from someone who as actually "done it."
Lloyd

[lloyd-ss]

And I realize that 2162 is too high of a velocity for lead bullets (supposedly) because the rifling will strip off the bullet, ...

That depends on the alloy used and a few other things.

I have shot cast lead at 2600 fps in a 30-06 without issues.

You can also coat the bullets with HighTek coating.  It works in powder burners with the hot gas and you need no gas check and no lube in the lube grooves.  I use it on my personal slugs to prevent leading and I have to clean my barrel a lot less.  Would work great if it evolves where these higher velocities are a reality.

Nick,
Very good!  Thanks for helping to kill the myth that non-jacked bullets won't work at high velocity.
Lloyd