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Hard cast though..... Can't push them too fast.If your shooting .357, 1000fps seems a little slow from what them puppies can zip along at...
Standard .22lr twist rate is about 1:16, .223 is about 1:9.. the main difference between the two is the speed of the bullet. Speed is a factor to consider regarding twist rate/stabilization of a bullet.Speed does not stabilize bullets, it is the rate of twist.
Whatever you are trying to say, velocity is a factor to consider regarding optimum twist rate/stability.. otherwise, velocity would be a constant in any twist rate calculator.. and it is not.>Standard .22lr twist rate is about 1:16, .223 is about 1:9.. the main difference between the two is the speed of the bullet. Speed is a factor to consider regarding twist rate/stabilization of a bullet.
The main difference between .223 and .22LR is the weight of bullet being stabilized and the length the bullet and the construction of the bullet and the bearing length of the bullet. Gee, maybe there really isn't that much similarity between them.
Precision Pistol centerfire shooting is usually done at 650-750 fps for 25-50 yards.
9mm pistol have a twist rate of 1:16 to 1:10, yet, for accuracy, they need to be about 1:25 to 1:35--talk to the folks in NRA Precision Pistol trying to get 9x19 to shoot accurately for competition against real guns like .45 Autos.
Most pistols could probably use a slower rate of twist, but they are almost all somewhere between 1:16 and 1:10, no matter what. Most pistol bullets have more in common with round ball and minnie ball than rifle bullets.
Weight is the determining factor for twist needed. The heavier the is in relation to its diameter the faster spin it needs to stabilize. 22lr's are 30-40 grains, .223 go from 50 to 80 grains with twists as fast as 1:7.Standard .22lr twist rate is about 1:16, .223 is about 1:9.. the main difference between the two is the speed of the bullet. Speed is a factor to consider regarding twist rate/stabilization of a bullet.
The determining factor? Then hold everything constant save the velocity in any twist calculator. Change it from 1000 to 3000fps. badabingo.Weight is the determining factor for twist needed. The heavier the is in relation to its diameter the faster spin it needs to stabilize. 22lr's are 30-40 grains, .223 go from 50 to 80 grains with twists as fast as 1:7.
It does not work that way. Its distance and RPM, not speed+RPM. A rifle that likes a lite bullet, 1:12, at 1000 FPS. The bullet will have rotated 1000 times at 1000 foot mark. Next, a heavier bullet that needs 1:6 to stabilize shot out of the same gun but at 2000 FPS. At the 1000 foot mark it will only have rotated 1000 times. No matter how fast it's shot RPM's at distance will not change.Change it from 1000 to 3000fps. badabingo.
http://www.bergerbullets.com/twist-rate-calculator/
We're talking about stability of a particular projectile here and then changing its velocity/speed only. Notice what happens.It does not work that way. Its distance and RPM, not speed+RPM. A rifle that likes a lite bullet, 1:12, at 1000 FPS. The bullet will have rotated 1000 times at 1000 foot mark. Next, a heavier bullet that needs 1:6 to stabilize shot out of the same gun but at 2000 FPS. At the 1000 foot mark it will only have rotated 1000 times. No matter how fast it's shot RPM's at distance will not change.
It does not work that way. Its distance and RPM, not speed+RPM. A rifle that likes a lite bullet, 1:12, at 1000 FPS. The bullet will have rotated 1000 times at 1000 foot mark. Next, a heavier bullet that needs 1:6 to stabilize shot out of the same gun but at 2000 FPS. At the 1000 foot mark it will only have rotated 1000 times. No matter how fast it's shot RPM's at distance will not change.
Here's a follow up, shot 2 loads back to back alternating back and forth at 2 targets side by side. shot 4 cylinders of each load, left target was the lighter load right target was the heavier. I then shot 12 rounds of each over the chronograph keeping the strings separate. All shots fired from the same 6" Security Six. The first load was aprox 900 fps and shot aprox a 2" group, it's been my go to load. Second load was 1/2gr more powder so was going aprox 950 fps and shot a group half the size of the first. Looking at the chronograph data the extreme spread dropped from 103 to 54 and the standard deviation dropped from 26 to 18. I think I'm on to something here and will shoot this in my other .357 to see if it likes this load as well. If I get similar results with the GP-100 I might bump the load one more 1/2 gr. and see what happens there.