Q. if a barrel has a 1:9" twist is this saying that after leaving the muzzle the bullet will rotate once fully in 9"? how is it measured? also how does the twist effect the bullets travel, will a 1:10" twist preform better than a 1:9" twist?
A. Longer bullets generally require a faster rate of twist. When you hear that a heavier bullet needs a faster rate of twist it’s because when its heaver than normal the bullet is generally longer.
It’s a combination of bullet speed, weight and design that leads to what rifling twist works best.
Faster twist rate can cause more wear on the guns bore and its rifling. And too fast of a twist can compromise the bullet even causing it to come apart in the air.
To say a bullet keep its revolution of say 1 in 9 as it travels through the air is wrong. As soon as the bullet leaves the bore it meets resistance from the air and moisture in the air which slows it down. So a bullet thats traveling with a spin of 1 revolution in 9 inches wont be doing so at say 100 yards because it going slower. This changes the ratio of spin per inch to some degree.
The bullets spin keeps it stable in flight. Take a kids top for example, when it spins fast it stands upright spinning in circles. As it slows down it becomes unstable and begins to wobble and then it falls over. A bullet spinning in flight without the correct spin will start to yaw then tumble and hit the target in a key hole effect. As it travels to the target while tumbling it looses it accuracy due to deflection from the air. If you ever shot an odd shaped rock out of a sling shot as a kid and watched them go crazy directions then you can see how a tumbling bullet can go all over the place.
I’m not much of a Wikipedia fan but this explains rifling pretty good;
http://en.wikipedia.org/wiki/Rifling
The effect of rifling applies to old black powder guns as well as modern guns. Now some big guns such as tanks may not have any rifling at all because the projectile deploys “fins” or stabilizers to spin it.
This article on smooth bores explains that;
http://en.wikipedia.org/wiki/Smoothbore
This modern smooth bore projectile technology has been used for shotgun projectiles used by the military. Check out this puppy;
http://media.photobucket.com/image/finned%20shotgun%20shells%20for%20the%20military/zarganuts/shotgun-fins.jpg
Here is the fag 12 round pictured above being fired at a target;
http://www.youtube.com/watch?v=cQYp9fOJ9VI
And this taser shotgun round with fins;
http://electronics.howstuffworks.com/gadgets/other-gadgets/taser-shotgun-shell1.htm
Some old black powder rifles had a 1 in 74 inch spin for lead round balls. And some newer BP rifles made for sabot conical may have a twist of 1 in 10.
Hope this helps some and that I didn’t give you a headache lol!
I sure have one now so I think another shot of Jack is in order!
It’s a combination of bullet speed, weight and design that leads to what rifling twist works best.
Faster twist rate can cause more wear on the guns bore and its rifling. And too fast of a twist can compromise the bullet even causing it to come apart in the air.
To say a bullet keep its revolution of say 1 in 9 as it travels through the air is wrong. As soon as the bullet leaves the bore it meets resistance from the air and moisture in the air which slows it down. So a bullet thats traveling with a spin of 1 revolution in 9 inches wont be doing so at say 100 yards because it going slower. This changes the ratio of spin per inch to some degree.
The bullets spin keeps it stable in flight. Take a kids top for example, when it spins fast it stands upright spinning in circles. As it slows down it becomes unstable and begins to wobble and then it falls over. A bullet spinning in flight without the correct spin will start to yaw then tumble and hit the target in a key hole effect. As it travels to the target while tumbling it looses it accuracy due to deflection from the air. If you ever shot an odd shaped rock out of a sling shot as a kid and watched them go crazy directions then you can see how a tumbling bullet can go all over the place.
I’m not much of a Wikipedia fan but this explains rifling pretty good;
http://en.wikipedia.org/wiki/Rifling
The effect of rifling applies to old black powder guns as well as modern guns. Now some big guns such as tanks may not have any rifling at all because the projectile deploys “fins” or stabilizers to spin it.
This article on smooth bores explains that;
http://en.wikipedia.org/wiki/Smoothbore
This modern smooth bore projectile technology has been used for shotgun projectiles used by the military. Check out this puppy;
http://media.photobucket.com/image/finned%20shotgun%20shells%20for%20the%20military/zarganuts/shotgun-fins.jpg
Here is the fag 12 round pictured above being fired at a target;
http://www.youtube.com/watch?v=cQYp9fOJ9VI
And this taser shotgun round with fins;
http://electronics.howstuffworks.com/gadgets/other-gadgets/taser-shotgun-shell1.htm
Some old black powder rifles had a 1 in 74 inch spin for lead round balls. And some newer BP rifles made for sabot conical may have a twist of 1 in 10.
Hope this helps some and that I didn’t give you a headache lol!
I sure have one now so I think another shot of Jack is in order!
What do you think about the practice of sending brag letters in Christmas cards?
Q. They tell about how rosy their life has been and how great the past year has been to them. For example, their son is class president, and their daughter is on the honour roll. Some of them brag about how many grandchildren they have and/or how fast they are collecting them. They talk about their extensive travels or what wonderful jobs their spouses or kids have. Nowdays, they brag about their electronic gadgets and their computers. The sun shines perpetually on these people. You would really think they knew Santa Claus better than anyone else, and they make other people feel sick and depressed. They even seem to imply that they are getting all these things because they have been good.
Is this practice in keeping with the spirit of Christmas?
Is this practice in keeping with the spirit of Christmas?
A. Hmm... not keeping with the spirit at all. We've got a family friend who sent those letters out every year until last year and instead she sent a family newsletter. For crying out loud, a newsletter. It had little blurbs for her children... 'Katie's Corner' and even one for the dog. She went on and on about how her son was a black belt and on the Honor roll and how her daughter was the best reader in her class and all this other bull crap that nobody really wants to hear on Christmas. I agree... they just want you think think they're something special. For them, Christmas is the time of year to let everyone know how great life is, even if it's only to avoid thinking about the downpoints. I don't buy a word of it though. It's great to share love and be friendly and even if people don't mean to brag, they do... and they shove the rest of us down. Whoever said, on this page, that you're 'not whorthy' to read those letters proablby has never recived such a Christmas card. I wish we could all brag and be happy for one another. It'd be great if Christmas worked that way, but it doesn't in our heads because the world bassically sucks.
There's an answer in here somewhere. Happy Holidays.
There's an answer in here somewhere. Happy Holidays.
Where's a good hotel to stay in with my family in Hong Kong?
Q. I'm planning to take my husband and 3 kids (aged 10, 12 &15) to their first trip in Hong Kong. We intend to shop for gadgets and visit HK Disney. Please recommend a reasonably priced hotel that's situated near shopping malls, the MTR, and with big enough rooms for kids. Thanks!
A. It might be difficult to find a hotel that can accomodate 5 people in one room and that is affordable. When I travel with family, I stay at the Metropark in Kowloon; it is a very good hotel, great location just off Kowloon Tong, nice amenities, great service, there is a swimming pool on the top floor which is great for the kids...However, the maximum number of people accepted in one room is 3, maybe 4. I believe there are some regulations on the number of people who can stay in one hotel room. My last stay there was last August with my 2 daughters, and I paid an average of 700HK$ per night for a double room, and they gave me an extra cot for free, you might be able to negotiate a good deal if you decide to take two adjoining rooms. If you don't mind staying out of town, the Silvermine Beach hotel is not bad and relatively affordable, and there is a very nice beach. It is located on Lantau, very accessible, near the Big Buddha, Disneyland, and very nice natural scenery, and only a quick ferry ride away from downtown HK or KL.
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