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9/22/2017 12:11:25 AM
Posted: 8/23/2005 3:30:50 PM EDT
Is there any relation between barrel lenght and bullet weight? If I have a short barrel would a certain weight of a bullet stabilize better than another? Such as a short barrel would better stablize a lighter weight? Sorry if this does not make sense.
Link Posted: 8/23/2005 3:33:30 PM EDT

Originally Posted By Cptbwst:
Is there any relation between barrel lenght and bullet weight?Yes If I have a short barrel would a certain weight of a bullet stabilize better than another?Yes Such as a short barrel would better stablize a lighter weight?Yes Sorry if this does not make sense.It made sense

Link Posted: 8/23/2005 3:42:00 PM EDT
Thanks "theshootersden"!!!! I needed that answer and I got it very quick!
Link Posted: 8/23/2005 4:03:40 PM EDT
Link Posted: 8/23/2005 4:28:46 PM EDT
So is there a guide or something for twists and weights for barrels?
Link Posted: 8/23/2005 4:34:16 PM EDT
[Last Edit: 8/23/2005 5:44:19 PM EDT by theshootersden]
For example:

A 1x9 twist in a 20- to 24-inch barrel allows for essentially the full range of bullet weights, 40 to 75 grains, as well as for the use of potentially frangible bullets. Hence, it represents the ideal twist for this caliber (.224) because of its versatility. A 16-inch barrel in the 1x9 twist will accurately launch all most bullet types in weights up to 69 grains. These are my findings...
Link Posted: 8/23/2005 4:35:25 PM EDT
In general:
1x7 Good twist for the 50-80 grain bullets. Excellent accuracy with 60 grain bullets and up.
1x8 Good twist for the 50-80 grain bullets. Excellent accuracy with 55 grain bullets and up.
1x9 Good all around twist ratio. Will shoot well with bullets anywhere from 40-75 grains in weight.
1x10 Good twist for the 40-62 grain bullets, but favoring the lighter side a little more.
1x12 Good twist for the 40-55 grain bullets.
1x14 Good twist for the 40-45 grain bullets.
Link Posted: 8/23/2005 4:39:23 PM EDT

Originally Posted By Cptbwst:
So is there a guide or something for twists and weights for barrels?



Good reloading manual.

It's a little more complex than just weight. It has as much to do with bullet length, where the bearing surface is in relation to the COM (Center Of Mass) and all this is related to the weight (mass).

Generally speaking heavier bullets require faster twist rates. The ideal twist will impart enough spin to stablize the bullet enough to let it rotate forward to follow the arc (keep the pointy end headed in the direction of travel).

Also barrel length does have a little to do with it. Stabilization has more to do with the rotation of the bullet, relative to it's trajectory, shape and COM. Shorter barrels impart less velocity, hence less rotation, than longer barrels of the same twist rate.

Totaly confused now?
Link Posted: 8/23/2005 4:47:50 PM EDT

Originally Posted By Halfcocked:

Originally Posted By Cptbwst:
So is there a guide or something for twists and weights for barrels?



Good reloading manual.

It's a little more complex than just weight. It has as much to do with bullet length, where the bearing surface is in relation to the COM (Center Of Mass) and all this is related to the weight (mass).

Generally speaking heavier bullets require faster twist rates. The ideal twist will impart enough spin to stablize the bullet enough to let it rotate forward to follow the arc (keep the pointy end headed in the direction of travel).

Also barrel length does have a little to do with it. Stabilization has more to do with the rotation of the bullet, relative to it's trajectory, shape and COM. Shorter barrels impart less velocity, hence less rotation, than longer barrels of the same twist rate.

Totaly confused now?



LOL, it is pretty confusing That's why I'm usually hesitant to go there, it always turns into a prove it ordeal...
Link Posted: 8/23/2005 4:56:23 PM EDT
[Last Edit: 8/23/2005 4:59:10 PM EDT by Halfcocked]
www.bergerbullets.com/catalog.htm

These are generally higher end bullets. You will notice that for the VLD (Very Low Drag) bullets the twist rate might seem a tad slow for the weight. That is because the shape of the bullet is such that more of the bearing surface is towards the back of the COM (long pointy nose).
Link Posted: 8/24/2005 1:12:33 AM EDT
Whoah! Ok. I'm taking from this then if you have the same bullet and twist but a deferent lenght of barrel you get either more or less velocity depending on the lenght of the barrel.hinking.gif
Link Posted: 8/24/2005 1:43:52 AM EDT
@ bigbore,

Given the same twist, barrel length HAS to do with stabilization. The more muzzle velocity, the more rotation, the more stabilization.
Link Posted: 8/24/2005 6:21:05 AM EDT

Originally Posted By Cptbwst:
Whoah! Ok. I'm taking from this then if you have the same bullet and twist but a deferent lenght of barrel you get either more or less velocity depending on the lenght of the barrel.



10-4
Link Posted: 8/24/2005 6:32:16 AM EDT
Link Posted: 8/24/2005 6:42:38 AM EDT

Originally Posted By bigbore:

Originally Posted By Keiler:
@ bigbore,

Given the same twist, barrel length HAS to do with stabilization. The more muzzle velocity, the more rotation, the more stabilization.



more stabilization I can understand a stool with 3 legs being stable, and a chair with 4 legs having more stabilization.

Can any physics experts explain to me how a bullet can be more stabilized? If the bullet is stabilized, isnt it "stabilized"?



Look at it this way for simplicity... Is a .22 caliber pistol as accurate as a .22 caliber rifle at 50 yards? It is not... Why? Because of the barrel length Chamber pressure and stabilization is the factor...
Link Posted: 8/24/2005 6:49:39 AM EDT
Link Posted: 8/24/2005 7:04:14 AM EDT
[Last Edit: 8/24/2005 7:25:46 AM EDT by QShok]

Originally Posted By bigbore:

Originally Posted By Keiler:
@ bigbore,

Given the same twist, barrel length HAS to do with stabilization. The more muzzle velocity, the more rotation, the more stabilization.



more stabilization I can understand a stool with 3 legs being stable, and a chair with 4 legs having more stabilization.

Can any physics experts explain to me how a bullet can be more stabilized? If the bullet is stabilized, isnt it "stabilized"?




More stabilized means to spin it faster but not too fast. Increasing twist rate or muzzle velocity will increase spin. Increasing barrel length increases velocity thereby increasing spin. A longer barrel with the same twist rate can give you "more stabilization" which helps with heavier/longer bullets.

Bullet velocity and spin slows down over time. A bullet can be perfectly stable then start to yaw or wobble at some distance away becuase it isn't spinning as fast. The faster you spin it the farther and longer it will be stable.

Over stabilizing is spinning it too fast. It will cause it to yaw shortly after leaving the barrel then correct itself when it's spin slows down enough.

Shok
Link Posted: 8/24/2005 7:18:12 AM EDT

Originally Posted By bigbore:

Originally Posted By theshootersden:

Look at it this way for simplicity... Is a .22 caliber pistol as accurate as a .22 caliber rifle at 50 yards?



Yes, it is just as accurate. You'll have to add a bit more elevation to the pistol to get the groups in the same place as the rifle, but that has nothing to do with accuracy.

By your logic a 13" barrel at 300yds, wont be as accurate as a 20" at the same distance?




No, Its not as accurate... It has everything to do with barrel length... Caliber, barrel length and range comes into play there... Adding windage and/or elevation to compensate is not comparable...

Why do you need to add elevation to achieve the same results? Chamber pressure/stabilization?

Link Posted: 8/24/2005 7:32:11 AM EDT
[Last Edit: 8/24/2005 7:36:04 AM EDT by MuRDoC]

Originally Posted By theshootersden:

Originally Posted By bigbore:

Originally Posted By theshootersden:

Look at it this way for simplicity... Is a .22 caliber pistol as accurate as a .22 caliber rifle at 50 yards?



Yes, it is just as accurate. You'll have to add a bit more elevation to the pistol to get the groups in the same place as the rifle, but that has nothing to do with accuracy.

By your logic a 13" barrel at 300yds, wont be as accurate as a 20" at the same distance?




No, Its not as accurate... It has everything to do with barrel length... Caliber, barrel length and range comes into play there... Adding windage and/or elevation to compensate is not comparable...

Why do you need to add elevation to achieve the same results? Chamber pressure/stabilization?





just because a slower round drops more does not make it less accurate, if you sill shoot it threw the same hole at 100yds, its the pattern, all bullets travel in an arch, some have a higher arch than others, the arch is affected by bullit weight and velocity. Bullit stabilization is a gyroscopic effect on the round, and that comes from the rate of twist.
Link Posted: 8/24/2005 7:53:16 AM EDT

Originally Posted By MuRDoC:

Originally Posted By theshootersden:

Originally Posted By bigbore:

Originally Posted By theshootersden:

Look at it this way for simplicity... Is a .22 caliber pistol as accurate as a .22 caliber rifle at 50 yards?



Yes, it is just as accurate. You'll have to add a bit more elevation to the pistol to get the groups in the same place as the rifle, but that has nothing to do with accuracy.

By your logic a 13" barrel at 300yds, wont be as accurate as a 20" at the same distance?




No, Its not as accurate... It has everything to do with barrel length... Caliber, barrel length and range comes into play there... Adding windage and/or elevation to compensate is not comparable...

Why do you need to add elevation to achieve the same results? Chamber pressure/stabilization?





just because a slower round drops more does not make it less accurate, if you sill shoot it threw the same hole at 100yds, its the pattern, all bullets travel in an arch, some have a higher arch than others, the arch is affected by bullit weight and velocity. Bullit stabilization is a gyroscopic effect on the round, and that comes from the rate of twist.



A round dropping more because its slower is the DEFINITION of less accurate. You are saying it has the same PRECISION which is something else entirely seperate from accuracy.
Link Posted: 8/24/2005 8:00:14 AM EDT
[Last Edit: 8/24/2005 8:00:56 AM EDT by theshootersden]

Originally Posted By DevL:

Originally Posted By MuRDoC:

Originally Posted By theshootersden:

Originally Posted By bigbore:

Originally Posted By theshootersden:

Look at it this way for simplicity... Is a .22 caliber pistol as accurate as a .22 caliber rifle at 50 yards?



Yes, it is just as accurate. You'll have to add a bit more elevation to the pistol to get the groups in the same place as the rifle, but that has nothing to do with accuracy.

By your logic a 13" barrel at 300yds, wont be as accurate as a 20" at the same distance?




No, Its not as accurate... It has everything to do with barrel length... Caliber, barrel length and range comes into play there... Adding windage and/or elevation to compensate is not comparable...

Why do you need to add elevation to achieve the same results? Chamber pressure/stabilization?





just because a slower round drops more does not make it less accurate, if you sill shoot it threw the same hole at 100yds, its the pattern, all bullets travel in an arch, some have a higher arch than others, the arch is affected by bullit weight and velocity. Bullit stabilization is a gyroscopic effect on the round, and that comes from the rate of twist.



A round dropping more because its slower is the DEFINITION of less accurate. You are saying it has the same PRECISION which is something else entirely seperate from accuracy.



+1 DevL...
Link Posted: 8/24/2005 8:02:40 AM EDT
[Last Edit: 8/24/2005 8:52:21 AM EDT by theshootersden]
By selecting different barrel twist and length you can change the way the bullet exits the barrel... A barrel with a faster twist will cause the bullet to exit the barrel earlier than a bullet launched from a slower twist barrel...
The harmonics of a barrel when being fired will cause the bullet to have an upward swing when exiting the barrel...An average velocity bullet will exit the barrel just before the peak of its upward swing. A faster bullet will exit the barrel earlier and exit slightly before an average velocity bullet, thus the angle of the upward swing of the barrel will be slightly less, causing the bullets launch angle to be less also, but the bullet is going faster and drops less... A slower bullet will exit later and the barrels upward swing will be higher and at a steeper angle when the bullet exits the barrel, thus the bullet is launched at a higher angle but is slower and will drop slightly more...



Here's something to look at... www.anzioironworks.com/barrel_length_vs_fps.htm
Link Posted: 8/24/2005 8:17:26 AM EDT
Link Posted: 8/24/2005 2:14:16 PM EDT
Yes, twist does play the greatest part in stability and the length of the rifle barrel has a direct influence on the velocity obtained from the cartridge for which it is chambered. Ballistically, longer is usually better, but not always the case...
Link Posted: 8/24/2005 2:49:17 PM EDT
[Last Edit: 8/24/2005 2:50:09 PM EDT by SWO_daddy]

Originally Posted By DevL:

Originally Posted By MuRDoC:

Originally Posted By theshootersden:

Originally Posted By bigbore:

Originally Posted By theshootersden:

Look at it this way for simplicity... Is a .22 caliber pistol as accurate as a .22 caliber rifle at 50 yards?



Yes, it is just as accurate. You'll have to add a bit more elevation to the pistol to get the groups in the same place as the rifle, but that has nothing to do with accuracy.

By your logic a 13" barrel at 300yds, wont be as accurate as a 20" at the same distance?




No, Its not as accurate... It has everything to do with barrel length... Caliber, barrel length and range comes into play there... Adding windage and/or elevation to compensate is not comparable...

Why do you need to add elevation to achieve the same results? Chamber pressure/stabilization?





just because a slower round drops more does not make it less accurate, if you sill shoot it threw the same hole at 100yds, its the pattern, all bullets travel in an arch, some have a higher arch than others, the arch is affected by bullit weight and velocity. Bullit stabilization is a gyroscopic effect on the round, and that comes from the rate of twist.



A round dropping more because its slower is the DEFINITION of less accurate. You are saying it has the same PRECISION which is something else entirely seperate from accuracy.



Do you not compensate for bullet drop? I thought that's why sights and scopes had elevation adjustments.

Drop has nothing to do with accuracy.
Link Posted: 8/24/2005 2:52:11 PM EDT

Do you not compensate for bullet drop?



Yep, you sure do, but lets not forget about windage too...
Link Posted: 8/24/2005 4:45:53 PM EDT
Whoa.

Lots of BS AND good info put forth above. Let's try and sort it out.

First, a shorter barrel does not necessarily mean more inaccurate than a longer barrel. A longer barrel will impart more Muzzle Velocity (MV) and will mean less drop over the the same distance traveled. This can make range estimation less of an issue with longer barrels, hence greater velocity, for the same round fired through two barrels of different lengths. This assumes both bullets are stabilized appropriatly.

Second, slow rounds ar NOT inherently more inaccurate or are those with greater verticle movement over their trajectory (high arcing bullets). I was in the artillery and we fire projectiles up into the air at angles higher than 45 degrees. They could be placed with in yards of each other 10 miles away. Consistency from round to round is what makes for accuracy.

Third, the gyroscopic effect (why a top when spinning fast doesn't fall over) is the force that stabilizes a bullet. Not enough spin will cause it to wobble or yaw. FOR LONG RANGES (over three hundred yards) if the bullet begins to fall at a rate that lets the bottom of the bullet develope pressure (the direction of travel is down some what but the bullet stays horizontal) the bullet will be over stabilized and it will start to wander in the direction opposite to the direction the bottom is rotating. This is how a curve ball moves. Again if it's consistent, the lateral distance will be the same from round to round and it will not be more inaccurate, it will just move to the left or right (depending on the direction of spin). It will move more at longer distances. It is not uncommon in high power shooting to have to add a click or two of windage for the 600 yard range on perfectly calm days. If the bullet is stabilized correctly, the bullet will tilt forward to keep the nose pointed in the direction of travel thus minimizing the affect.

There is a lot of good info in the ammo oricle and over at the compitition forums.
Link Posted: 8/25/2005 2:59:32 AM EDT
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