December 18, 2020 at 7:41 am #536213
Aerodynamics and physics all tell us that dimples in golf balls improve its flight. I was just wondering if we could apply the same principles to the airgun pellet? Both the golf ball and the pellet are projectiles flying through the same air, subject to the same rules of aerodynamics. I tried to ask google if anyone has done it, but no luck there.January 19, 2021 at 2:33 pm #536305Kindly ‘Ol Uncle HootParticipant
I don’t have dimples and my pellets fly just fine!
HootMarch 4, 2021 at 12:51 am #536398sawtimeParticipant
wow Hoot good to see you still around😄😄😄😄
This is the first time i have been in here for years!!!
Been working hard, got a few FX’s since last login
Life has been good considering the 19 shit
sawtimeMarch 4, 2021 at 5:30 am #536399
great to hear from you again Uncle Hoot… been ages actually.. glad to see it is my post you replied in centuries.
I am pretty sure you have dimples somewhere your old eyes can not see… but you knew that all along.
Maybe I will experiment with dimpled pellets somehow and see how my theory goes.March 4, 2021 at 10:19 pm #536405RowdyParticipant
If the pellets were round balls the dimples might help indeed but dang they’d be really small dimples considering the diameter of a pellet as compared to a golf ball…
Now if you just do a good search and some good reading on the Diablo design of the pellet, head shape takes on the design of the big end of a raindrop then you get the waisted skirt at the small end of the raindrop; the skirt of the pellet does three main things.
1- helps stabilize the pellet in flight.
2- capturing propulsion from the air rifle.
3- then the cup side of the skirt captures the energy from the rifle pushing the pellet through the barrel with the trailing edge of the skirt indexing itself with the rifling, to achieve the best possible trajectory and point of impact.
Now all this is applied to pellets and projectiles under the speed of sound. The Diablo design works really well. Approaching or over the speed of sound they tend to fly around a little more so than bullets…
In the cases of solid rounds those are not well suited for fast rifled barrels, most often they are like a 1 in 38″ twist or longer, even some barrels being smooth bore for them.
They never equal the accuracy of the Diablo design that I’ve ever seen, I will have to admit, I love shooting round ball. There’s just something about the way the round ball impacts things that I really like, they just don’t have the range and accuracy that most of us require.
Now, we take the modern day PCP rifle builders and have them build the semi-auto PCP.
Let’s make it either .22 caliber which is hard to find, but is type “F” in shot size or the easier to find #3 shot @ which would be .25 and a bit more heavy on impact, incidentally the 22 caliber type “F” weighs in @ 14.3 grains, I use these in several old Benjamin air rifles I have in smooth bore.
Type “F” is a tight fit, which would need a lead in on the chamber, for semi-auto, I buying it by the pound, which is cheap as compared to our other pellet ammo.
The barrel @ 1 in 38″ twist, it would be very interesting to see how that would pan out.
Might be an interesting test for the FX- smooth twist barrels in the slow twist rates…
The round ball would be much easier to magazine a bigger volume, in either caliber also. Which would be a bennie 🙂 which we all like the higher cap mags…
.25 caliber round ball ammo at 950 ft per second would be pretty badass semi auto wise, long as it’s accurate.
Then, I guess you would need to be trying The dimple on the 25 caliber ball ammo!!! 🙂April 19, 2021 at 10:23 am #536520John StezParticipant
They would be very difficult and expensive to manufacture correctly. The dimples would have to be perfectly and evenly formed and spaced, or there will be an uneven pressure differential. If possible, it would increase the BC a bit. Most of a pellets BC issues is the skirt. Would be cool to see though.April 25, 2021 at 9:51 am #536532
I feel and I think people are just content with slugs than improving the classic diabolo pellet.
My pcp can not handle slugs, and I feel I have to live with it as it is.. to just be content with what I have.
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