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Discussion Starter · #1 ·
When I talk about firearm safety with someone new to shooting, I refer to the danger as a line extending straight out from the muzzle. I know that this is technically wrong, but they would likely roll their eyes if I called it an arced, overstabilized helix.

When you fire your a gun, the bullet wants to exit the muzzle in a straight line. As the bullet emerges, random variables such as the irregular escape of the propellant gases, bullet imperfections and the absence of the barrel to guide it, cause the bullet to wobble. This wobble, or yaw, makes the air flowing around the bullet to push it in the direction of yaw. Due to gyroscopic forces, a spinning bullet will try to move sideways to the direction that it is pushed. As the bullet starts to move, the process repeats itself, leading the bullet to fly in a spiral path. Many factors come together to settle the bullet into a steady spiral. The spiral is usually of such a small diameter that it's ignored, but it is there.

As the bullet proceeds toward the target, the nose is asked to turn downward to continuously point in the direction of travel. If the bullet has the minimum spin to stabilize it, the nose should gently turn to point in the direction of travel as gravity pulls the bullet earthward. However, if the bullet is spun too fast it will resist this change, resulting in yaw, spiral and drift more than necessary. The yawing will slow the bullet far more quickly than zero-yaw. The spiral will also grow more pronounced, yielding inconsistent groups. Yes, bad things happen when you spin the bullet too fast or too slow.

Modern rifle bullets almost always leave the muzzle at a speed faster than sound. High velocity has many virtues for a rifle bullet. As the rifle bullet flies through the air, it slows. At some distance, the rifle bullet will have slowed to slightly faster than the speed of sound. When this happens, some of the shock waves emanating from the bullet begin to shift fore and aft. Vibrations set in and the bullet begins to wobble, thus accentuating accuracy problems. For this reason .22LR target shooters use subsonic ammo and precision rifle shooters try to maintain supersonic velocity of their bullet until it reaches the target.

So, when someone tells you that the bullet flew straight from the rifle to the target...they lied. ;)
 

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thanks for the 101 refresher!

and the very short lives they have[just doing there job]


i guess i have lied, about my bullets in the past .

thank you for shining the LIGHT of truth/fact upon me!




thanks. :bow01:
 

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Here's a question for some.:

Everything else being equal, what bullet/cartridge generally shoots tighter groups at 300yds than it does at 100yds?

The ones that have experience with this round wait and see if someone else knows the answer.
 

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Discussion Starter · #4 ·
TODD 3465 said:
Here's a question for some.:

Everything else being equal, what bullet/cartridge generally shoots tighter groups at 300yds than it does at 100yds?
This may be a quirk caused by the lessened yaw and nutation at 300 yards versus that occuring at 100 yards. My intuitive thinking is that this phenomenon would only manifest itself in a case where the shot-to-shot dispersion was much smaller than the nutation. As a matter of physics, accuracy should degrade as range increases.
 

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i think it's the?

steel core penatrator [du] rds. out of the m-1 abrams main gun!



thanks.
 

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brasshammer- Close, it is a relatively large round but not that large.

A Clue:There's a hint at what it is on every page of this site.
 

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well! my second P-O-IMPACT

will be the .50 cal bmg


i shoot one my self, [a grinning scope eye, every time!]


but the cost, driving time , it just sets basically,




although, snapping the heads of a 350 chevy in half is pretty fun at 400-500-yards!

thanks.
 

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That sounds like fun Brass Hammer. Ever it the gas tank and have the car explode in flames?

RIKA
 

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no ! not yet, rika!

i got a 'moter-head' buddy that supplies me a lot of targets.

setting up, and shooting,across a desert valley[ i.e. out there!]

the exploding gas tank will leave alot of smoke[i.e hard to E-AND-E]


although, a 20lb. propane tank with the blue-tip projos are heap big fun!




thanks.
 

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While this 300 yd condition is rare, I've read of it being manifested with super-accurate rifles and ammo.
 
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