Shootin a 223 in the rain, ? for you Pros
- Thread starter BeltfedMG
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Couple factors here:
a) The HP tends to give more consistent aerodynamics
b) The cavity displaces weight outward where it will help with gyroscopic stability. The closer mass is to the axis of rotation, the less gyroscopic stability it imparts. A 200gr FMJ is generally going to be less stable than a 200gr JHP of the same caliber.
627PCFan
Member
For those of you whom dont know Ed minored in Meteorology in college 
rcmodel
Member in memoriam
Do they call Time-Out for a Rain-Delay in a war if it starts raining?
There is no effect at all, other then if it's really pouring, you can't see to shoot very far.
BTDT!
rcmodel
There is no effect at all, other then if it's really pouring, you can't see to shoot very far.
BTDT!
rcmodel
blackhawk2000
member
LOL Ryan . . .
In 40+ years of trigger pulling, more than 25 years of precision shooting and over ten years of 1/4 minute groups on the internet with this very keyboard and another that was just as accurate but got shot out, I have never heard of such a thing and would love to review the source . . .
A hollow point gives more consistent aerodynamics? How can a ragged hole in the tip be more consistently formed than a smooth, round FMJ? It just isn't, it's just a place to end, to leave the inconsistencies where they'll do the least harm.
Moving the weight outward from the center of form increases the influence of any imperfections/imbalances. Higher RPM also increases gyroscope stability (while also increasing the effects of any imperfections), yet the benchrest crew spins their bullets as slowly as possible, since spinning them more than necessary is proven counterproductive to good accuracy (less than 1/10th inch groups at 100 yards). It costs the same for a 1:7 barrel it does for a 1:14, if accuracy lived at greater gyroscopic stability, everybody would go there, but, they just don't. They only spin the bullet just fast enough to keep it stable and nose on, nothing more. Go figure.
The 200 grain FMJ in the cited example will actually have a less perfect base, thus less perfect uniformity, thus less perfect accuracy, than a match grade BTHP. Tip design/shape is the tertiary concern.
http://www.fbodaily.com/archive/2002/10-October/30-Oct-2002/FBO-00195130.htm
http://www.thegunzone.com/556faq-nb.html
A "perfect point" behind a bubble . . . LOL, that guy lives in a perfect bubble. I wish they would pay those guys enough to afford a research computer and internet service. I just HATE when publications just make up stuff when they don't know anything about something. I enjoy SOF from time to time, but not for the precision of their technical writing. Pardon me for saying so, but that whole article reads like a machine gunner trying to explain the (inconceivable) nuances of the 1,000 yard benchrest game.
kingjoey, where did this information come from?kingjoey said:
In 40+ years of trigger pulling, more than 25 years of precision shooting and over ten years of 1/4 minute groups on the internet with this very keyboard and another that was just as accurate but got shot out, I have never heard of such a thing and would love to review the source . . .
A hollow point gives more consistent aerodynamics? How can a ragged hole in the tip be more consistently formed than a smooth, round FMJ? It just isn't, it's just a place to end, to leave the inconsistencies where they'll do the least harm.
Moving the weight outward from the center of form increases the influence of any imperfections/imbalances. Higher RPM also increases gyroscope stability (while also increasing the effects of any imperfections), yet the benchrest crew spins their bullets as slowly as possible, since spinning them more than necessary is proven counterproductive to good accuracy (less than 1/10th inch groups at 100 yards). It costs the same for a 1:7 barrel it does for a 1:14, if accuracy lived at greater gyroscopic stability, everybody would go there, but, they just don't. They only spin the bullet just fast enough to keep it stable and nose on, nothing more. Go figure.
The 200 grain FMJ in the cited example will actually have a less perfect base, thus less perfect uniformity, thus less perfect accuracy, than a match grade BTHP. Tip design/shape is the tertiary concern.
Who'd have ever figured SOF would get their technical details mixed up [/sarcasm], but the MK 262 Mod 0 is actually a preliminary load using a 77 grain SMK w/o cannelure, which is indeed a true hollow point, with a hole in the nose, with a cavity behind it, with a closed-jacketed boattail base. The current MK 262 Mod 1 is the same thing with a cannelure, a 77 grain Sierra Match King.Blackhawk said:
http://www.fbodaily.com/archive/2002/10-October/30-Oct-2002/FBO-00195130.htm
http://www.thegunzone.com/556faq-nb.html
A "perfect point" behind a bubble . . . LOL, that guy lives in a perfect bubble. I wish they would pay those guys enough to afford a research computer and internet service. I just HATE when publications just make up stuff when they don't know anything about something. I enjoy SOF from time to time, but not for the precision of their technical writing. Pardon me for saying so, but that whole article reads like a machine gunner trying to explain the (inconceivable) nuances of the 1,000 yard benchrest game.
GooseGestapo
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EShell;
Much of the information that has been thrown around here is in the various Sierra reloading manuals. They go into quite some depth in discussing supersonic aerodynamics.
[I don't design or build aircraft, I just fly them. (and teach others how to fly them), hence, I know just enough about aerodynamics to embaress myself in front of those who do.]
They (Sierra) also discuss the hollow point vs. FMJ effect. When closing the base of a FMJ, any slight differences in metal density or jacket unformity manifests itself in inconsistencies there. I've got a batch of Federal FMJ .224" 55gr bullets. It's very obvious looking at the base of the bullet that the edge of the jacket is eccentric. Look at the tips of the Sierra hollow point bullets. They are almost always irregular. Hence, Sinclair makes a "Meplat Unformer" that is something like a pencil sharpner for cutting the tips "straight".
There is "something" to a lot of the foregoing discussion.
A accurate FMJ "can" be made. It just costs a LOT more to do it than with a HP. After all, the bullets have to be "affordable" to be shot down range.
Much of the information that has been thrown around here is in the various Sierra reloading manuals. They go into quite some depth in discussing supersonic aerodynamics.
[I don't design or build aircraft, I just fly them. (and teach others how to fly them), hence, I know just enough about aerodynamics to embaress myself in front of those who do.]
They (Sierra) also discuss the hollow point vs. FMJ effect. When closing the base of a FMJ, any slight differences in metal density or jacket unformity manifests itself in inconsistencies there. I've got a batch of Federal FMJ .224" 55gr bullets. It's very obvious looking at the base of the bullet that the edge of the jacket is eccentric. Look at the tips of the Sierra hollow point bullets. They are almost always irregular. Hence, Sinclair makes a "Meplat Unformer" that is something like a pencil sharpner for cutting the tips "straight".
There is "something" to a lot of the foregoing discussion.
A accurate FMJ "can" be made. It just costs a LOT more to do it than with a HP. After all, the bullets have to be "affordable" to be shot down range.
GooseGestapo,
I actually think that you and I are on the same page here. . . my several forgoing posts relate right back to the points you make.
I'm very familiar with the theory of meplat truing, which actually works to make the BC more uniform (vs improving absolute accuracy), thus reducing vertical dispersion at extended ranges due to varying times of flight.
OTOH, are you saying that what kingjoey had said was sourced from Sierra?
I actually think that you and I are on the same page here. . . my several forgoing posts relate right back to the points you make.
I'm very familiar with the theory of meplat truing, which actually works to make the BC more uniform (vs improving absolute accuracy), thus reducing vertical dispersion at extended ranges due to varying times of flight.
OTOH, are you saying that what kingjoey had said was sourced from Sierra?
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