Wondering about twist rates
I was looking to build my condor in to one of theses heavy hitters like a 308, 9mm some thing like that I was just wondering if some one can help me out on a good twist rate for a given calaber . hope this is the place to post this. Sorry for spelling I know I messed up some ware. Tanks every one
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I really don’t think it would be a waste. You’d be using a aerodynamic bullet, instead of a pellet. The sound barrier would not be the speed limit. It may not be heavy enough to suit you, would be for me! Would be the simplest way to eliminate using pellets. The technology is available now and works-proven here on the tag.
Sam 😕
Thank been doing a lot of looking and reading I for sure under stand want u are saing it just those jacked ones look crazy but yes u are right for hunting the 308 lead would hold much more energy. But this makes me have to ask how many shots from a tank like 2? lol guess it dosnt matter it will only take one shot and u can stop a tank . K not really but u guys get it
The greenhill formula does not apply well to airguns, it’s main use is predicting stability in supersonic projectiles.
Why would you want to use a sabot? for me, using a .308 gives the advantage of having a larger, heavier bullet hit the target with more energy than a .22 or .25… using a sabot goes the other way, takes the energy off the target rather than putting more energy into the target. Kinda a waste. The only advantage you would gain over a stock .22 condor is using jacketed bullet .
In 308 at subsonic velocities you’d need around 1-10 to stabilize up to around 180g bullets but depends on the bullet design.
walt
I tryed that the air leaks out lol. No real setting whats the length with top hat off.
I tryed that the air leaks out lol. No real setting whats the length with top hat off.
Depends on what your tophat setting is!!
You can pull the tophat and stem out with the tank full 😉
Thanks everyone for your help. Question any one know the length of the tophat to the end of the talon steam. I wana make another one but I dont wana drain the tank again lol. Thanks
The Greenhill formula is an old way of calculating the twist rate needed to stabilize any projectile. Z-hat barrel works has the formula on their website so you can calculate the twist rate you need for the projectile dia. , weight and velocity:
http://www.z-hat.com/twistrate.htm
It’s not designed for hollow airgun pellets or sabot loads, but it should get you in the ballpark.
Cool link thanks again and thats kinda what I though but hay thats y I asked.
I don’t know? Seems 30 to 60yds would be more realistic! These are probably what you would use. : http://www.reloadersauction.com/30-M1-Carbine-cast-bullets-250ct,name,139338,auction_id,auction_details
Go to an online ballistics calculator an plug in caliber, BC, MV, weight-etc…. http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi
I’d also guess muzzle velocity around say 800fps? Zero @ 50yds using .308-130gr bullet drops 13 inches @ 100yds, yields 165 foot pounds.
Sam ❓
K . And thanks again . any idea on how it dose at like 100 yards if that even posable lol
If you try the sabot, use any .224 Jacketed bullet, you want too! Cast lead, use .308 lead only bullet. You could use a .224 lead bullet with the Sabot, but not necessary. Use either with sabot. I don’t know if a lead cast bullet is available for .224 caliber?
Sam 😎
that talon looks crazy those sobot thing look crazy .ill look in to those and just to make sure im understanding this. I need a 308 barrel and the sabot fittings then .224 bullets made of soft lead. Then bigger valve and bla bla bla lol thanks for the help one more thing your saying a 1 &16 twist will work with what I said above
1 in 16 will work.
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Never thought about how u can probley go past the speed of sound that thems to open the bag of how pcp rifles are so called the dark side lol these guns are evil lol. Expectial when all of the mad scientest start getting invalved. but thanks again. When I finaly get this done ill be Sure to show everyone that has helped . This stuff to me is a cake walk I just dont wana waste my time with trial and mestake for the 5 years . But sure glad people have so it helps me out. Thanks again any more info is welll wanted