.308 Build
Ordered all the pieces from AF today so I can build my .308 Condor. Frame, trigger asembly, power wheel, fore arm grip. I have 28″ barrel and bigbore Blod valve. I will make everything else. Lathe is going to be here around 12:00 tomorrow. Can’t wait to start making things on a real lathe. I will then have .22 .25 and .308. Want to try and break 400 fpe with .308.
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Still working on valves Doug?
How about the solution to tank dumps?
Time to revisit this topic :-))
Wow! Thats some exotic stuff you are doing! You dont really have anywhere else to go once ya get on the airgun crack, only other gas with less mass is also too cumbustionable, huh?
At what pressure do you charge the helium to? Is helium easier to compress to higher pressures?
Surely sounds like an addictive and expensive habit to get hooked on!
Breaking the sonic barrier doesnt effect accuracy with these heavier bullets?
I shot the .308 on helium a couple of weeks ago.
158 gr 1154 fps 467 fps
Second shot off same fill
118 gr 1275 fps 425 fpe.
If I would have shot the 118 gr first it would have been over 1300 fps.
I will try again with 171 gr and see if I can break 500 fpe.
It only took 2.5 mildots of hold over at 300 yds. Amazing how fast it got there also.
Howdy Walter!!! 😀 \
Way back iinthe day, I was toying with teh Idea of bullet shooting and getting high velocity and fpe. You said NO WAY! Can’t be done with air! Do you remember??/ HUH—HUH??? And then you went and did it your self.
Sadly, you must have posted some of your results during my absence with that damed eminent domain move. It about ruined us.
Where can I see your leading edge builds? I would love to see them!
Watched Dunham the other night. Made me think of you. Walter’s the MAN!!! :8:
The older I get, the more I see myself getting more and more like him! 😳 😆
K/M, remind me what was impossible? Fergettful these days.
I am soooooo busy working very little time for playing……….
Well, I see that he has posted on teh 4500 psi boottle thread. Missed the old fart! 😀
Where is old grumpy any way. I see him on the yellow from time to time. With the success he has had with the Big Bore conlors, I would think he would post more about them. May be he is affraid that the Canadian Gov. will knock on his door. 😯
Well, we do have one member who swore he could do the numbers. sort of. Walter. But he said all of this was impossible when I was playing what “if” with it several years ago. Nope, can’t be done said old grumpy Walter. Then he went and dissproved his OWN theroies himself, by doing it himself. He proved that saying a thing cannot be done, does not PROVE a thing cannot be done! 😆 😉
My hats off to him for doing a thing, when even he himself thought it could not be done.
Knife
UFB!!!!!
Amazing ……. just simply amazing.
How much farther can you push the limit? Do you feel that you are pretty close to the point of diminished returns?
Surely there’s a practical upper limit (or even an impractical limit) to what a mechanical valve can do. It would be interesting if there was a slide ruler/pocket protector engineering type that could demonstrate some predictive mathematical formula of some sort…… :geekn:
Excuse me for being a greenhorn and a newbie but what is the theoretical limit to the velocity achievable for a given volume and pressure of common air or even helium?
Obviously there exsists many other mechanical factors and forces to overcome in this application. Seemingly it appears that overcoming the force of air against the valve vs the force required to open that valve and the timing of equalibrium before it finally spits out the pill at the end of the barrel. The simple straight through design of the airforce valve as it dumps straight into the breech with minimal obstruction or change of flow direction surely is a big advantage to extract the full energy potential of the expanding gas. I just wonder if there is any type of engineering mojo that can be employed to manipulate the fluid dynamics of the expansion of the gas to further extract the energy potential in a most efficient timing or places as it does its work? ??
Can it be manipulated thru venturi effect or expansion chambering or pressure foils or some exotic pratical application of physics?????
I dunno, I am just pondering and throwing it out there for the sake of conversation and topicality!
DAMN AWESOME STUFF YA DOING THERE DOUG!
I will be very happy to just get 80% of what you have gotten in those .257 builds you have done for the few very lucky guys out there! Man I can hardly wait! :4:
Time for a little Elephant and Woosel hunt’n! 😀
Knife
WOW :5:
WOW, what a power-house!!
Doug, does numbers are music to my ears :6: . You still plan on opening up the lead in for 200 grain+ slugs?
Well I’m still working my way up towards 400 fpe in .308.
I put my valve in my HPA tank today.
4000 psi fill
TH .070″
171 gr 933 fps 330 fpe
158 gr 960 fps 323 fpe
118 gr 1048 fps 287 fpe
I will open the TH up to .085″ and see if it gains any or just uses more air.
It will make 500+ fpe on helium as soon as I feel like pumping up a tank full and putting on ear protection. The recoil and noise is something else right now.
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Still making them.
You have issues with tank dump?