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Advanced Marksmanship I need DOPE!!! Snipers please help

C

camomallninja

Sergeant
Full Member
Minuteman
Mar 9, 2009
235
0
So I went to this website and filled everything out the best I could.

http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

But realized the clicks were a bit off I am new at this and here is what I noticed.

at 100 yards I am dead on middle but at 300 it shot about 1MOA to the right! I shot another rifle I have same results 1MOA to the right? There was no wind! so after researching I learned about (Spin drifting) is there a formula for this? I need some pointers.


Thanks guys
 
Re: I need DOPE!!! Snipers please help

Spin Drift is a Bitch... not only will she divorce you, take your money, eat your dog, but she'll also fuck your best friend.

Good luck with that...
 
Re: I need DOPE!!! Snipers please help

Gyroscopic drift (Spin drift)Even in completely calm air, with no sideways air movement at all, a spin-stabilized projectile will experience a spin-induced sideways component. For a right hand (clockwise) direction of rotation this component will always be to the right. For a left hand (counterclockwise) direction of rotation this component will always be to the left. This is because the projectile's longitudinal axis (its axis of rotation) and the direction of the velocity of the center of gravity (CG) deviate by a small angle, which is said to be the equilibrium yaw or the yaw of repose. For right-handed (clockwise) spin bullets, the bullet's axis of symmetry points to the right and a little bit upward with respect to the direction of the velocity vector as the projectile rotates through its ballistic arc on a long range trajectory. As an effect of this small inclination, there is a continuous air stream, which tends to deflect the bullet to the right. Thus the occurrence of the yaw of repose is the reason for bullet drift to the right (for right-handed spin) or to the left (for left-handed spin). This means that the bullet is "skidding" sideways at any given moment, and thus experiencing a sideways component.[20][21]

The following variables affect the magnitude of gyroscopic drift:

Projectile or bullet length: longer projectiles experience more gyroscopic drift because they produce more lateral "lift" for a given yaw angle.
Spin rate: faster spin rates will produce more gyroscopic drift because the nose ends up pointing farther to the side.
Range, time of flight and trajectory height: gyroscopic drift increases with all of these variables.
Doppler radar measurement results for the gyroscopic drift of several US military and other very-low-drag bullets at 1000 yards (914.4 m) look like this:

Bullet type US military M193 Ball US military M118 Special Ball Palma Sierra MatchKing LRBT J40 Match Sierra MatchKing Sierra MatchKing LRBT J40 Match LRBT J40 Match
Projectile weight (in grain) 55 gr 173 gr 155 gr 190 gr 220 gr 300 gr 350 gr 419 gr
Projectile diameter (in inches and mm) .223 in / 5.56 mm .308 in / 7.62 mm .308 in / 7.62 mm .308 in / 7.62 mm .308 in / 7.62 mm .338 in / 8.59 mm .375 in / 9.53 mm .408 in / 10.36 mm
Gyroscopic drift (in inches and mm) 23.00 in / 584 mm 11.50 in / 292 mm 12.75 in / 324 mm 3.00 in / 76 mm 7.75 in / 197 mm 6.5 in / 165 mm 0.87 in / 22 mm 1.90 in / 48 mm

The table shows that the gyroscopic drift is rather variable and no clear trend is easily distinguishable.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body">So I went to this website and filled everything out the best I could.

http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

But realized the clicks were a bit off I am new at this and here is what I noticed.

at 100 yards I am dead on middle but at 300 it shot about 1MOA to the right! I shot another rifle I have same results 1MOA to the right? There was no wind! so after researching I learned about (Spin drifting) is there a formula for this? I need some pointers.


Thanks guys </div></div>

that is also why it is called DOPE.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chiller</div><div class="ubbcode-body">so....

at 100 shoot all zero and at 300 have 1moa left.....problem solved..... </div></div>

yeah what about 400 500 600?
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chiller</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body">So I went to this website and filled everything out the best I could.

http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

But realized the clicks were a bit off I am new at this and here is what I noticed.

at 100 yards I am dead on middle but at 300 it shot about 1MOA to the right! I shot another rifle I have same results 1MOA to the right? There was no wind! so after researching I learned about (Spin drifting) is there a formula for this? I need some pointers.


Thanks guys </div></div>

that is also why it is called DOPE. </div></div>

Yeah I feel like I am on drugs!
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chanonry</div><div class="ubbcode-body">Even if you buy into Spin Drift, it will not produce 1 moa at 300 yards? </div></div>

I shot a .223 Savage and a Savage 30-06 and both grouped SUB MOA but 1MOA to the right.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chanonry</div><div class="ubbcode-body">Even if you buy into Spin Drift, it will not produce 1 moa at 300 yards? </div></div>

I shot a .223 Savage and a Savage 30-06 and both grouped SUB MOA but 1MOA the left </div></div>

And people wonder why I rant about it... take this guy and times him by 100X and that is the reality of those who walk in the door thinking this way.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chanonry</div><div class="ubbcode-body">Even if you buy into Spin Drift, it will not produce 1 moa at 300 yards? </div></div>

I shot a .223 Savage and a Savage 30-06 and both grouped SUB MOA but 1MOA to the right.</div></div>

http://www.snipershide.com/forum/ubbthreads.php?ubb=postlist&Board=11&page=1

Pay the money, watch "trigger school". Watch it again.

Now, proceed to dryfiring...a lot.
 
Re: I need DOPE!!! Snipers please help

You guys are pretty messed up. The guy asks a legit question and you F with him. Dude, don't listen to these clowns. This is whats needed to get you shooting straight, SpinD .
 
Re: I need DOPE!!! Snipers please help

If it were me I'd head to the range, set up a target at 100 yards. Take a 4ft level, draw a verticle line about 3ft tall and near the bottom but a horizontal line. That is your target. Crank your scope down to hit that dead center, crank 1 full turn up, still aim at that same target, crank it one full turn again, shoot the same spot and if you have room do it one more time. I'll venture to say you're tracking off. Just that the scope isn't tracking <span style="font-weight: bold">perfectly</span> verticle as you crank it up.

There is a thread on here somewhere that will help you get that taken care of.
But, I could be wrong. At least something to try that is most often times what is wrong.

Then again, it could be SD, Corri... something or another affect, full moon, UFO flying or possibility of a slight breeze between you and the target you can't see. But since my gun only has a 15" barrel and only shoots out to 1000 yards that don't affect me, they have built in immunity and all that uber elite stuff only affects anything longer than 15 1/2" length barrels
smile.gif


Good luck

Topstrap
 
Re: I need DOPE!!! Snipers please help

your rounds are impacting 3.6 inches to the right only at 300 yrds. I do not persieve spin drift is the problem. I think trigger control, breathing, or somthing behind the stick is causing it. If not must be a extreamly slow round with an extreamly high trist rate.
I honestly dont percieve spindrift a problem at the relitivly close range of 300 yrds in suppersonic rounds. At least not pulling 3.6 inches out of range. 3.6 (1 mil)inches at 500yrds mmmmmmmmm maby. I think maby place the rifle in a sled and see. at least it would tell you if you are flenching or jercking the trigger. If not record riffle info, bullet info, and adjust for impact.
 
Re: I need DOPE!!! Snipers please help

Unless you are a Grand Master, Hi Power Champion, or F Class shooter who routinely cleans the course of fire winning by "X" count, you are not seeing SD... especially inside 800 meters.
 
Re: I need DOPE!!! Snipers please help

awe hell Frank, but it just can't be their fault. I mean hell, their rifle is perfect, they're expert marksmen w. top notch equipment, and mad wind reading skills... maybe it's corliolis effect at 300yds
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chanonry</div><div class="ubbcode-body">Even if you buy into Spin Drift, it will not produce 1 moa at 300 yards? </div></div>

I shot a .223 Savage and a Savage 30-06 and both grouped SUB MOA but 1MOA to the right.</div></div>

I am sure they did. The results you observed were not however a result of Spin Drift.

Fundamentals?
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: former naval person</div><div class="ubbcode-body">Could be as simple as the 100 yard zero isn't a true zero. </div></div>

WhatIWasThinkin' . . . . . .

BMT
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Topstrap</div><div class="ubbcode-body">If it were me I'd head to the range, set up a target at 100 yards. Take a 4ft level, draw a verticle line about 3ft tall and near the bottom but a horizontal line. That is your target. Crank your scope down to hit that dead center, crank 1 full turn up, still aim at that same target, crank it one full turn again, shoot the same spot and if you have room do it one more time. I'll venture to say you're tracking off. Just that the scope isn't tracking <span style="font-weight: bold">perfectly</span> verticle as you crank it up.

There is a thread on here somewhere that will help you get that taken care of.
But, I could be wrong. At least something to try that is most often times what is wrong.

Then again, it could be SD, Corri... something or another affect, full moon, UFO flying or possibility of a slight breeze between you and the target you can't see. But since my gun only has a 15" barrel and only shoots out to 1000 yards that don't affect me, they have built in immunity and all that uber elite stuff only affects anything longer than 15 1/2" length barrels
smile.gif


Good luck

Topstrap </div></div>

Box test lol
 
Re: I need DOPE!!! Snipers please help

I GOT SOME SPIN D!!! Not only does it taste great but it gave me the boost of energy I needed.... PS you guys are fuckers for fucking with me... it was funny I have to admit.
 
Re: I need DOPE!!! Snipers please help

Dude, people aren't kidding about testing your scope, making sure everything is square as well making sure you're not overly canting the rifle. More than likely you have a shit trigger press, but who can say without seeing it.

It is NOT SD and anyone telling you they are dialing SD inside 800m is more than likely dialing a piss poor trigger pull, or canting their rifle, or their equipment is not Square. It is not SD at 300, period !
 
Re: I need DOPE!!! Snipers please help

Listen to LL this man knows his stuff.. He gets paid to teach people how to shoot.... So go back to the fundamentals and start figuring out what went wrong. Check your rifle. Once you have enough rounds down the tube you will know what went wrong before you see the hit. LL gets paid to do this listen!
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: force_multiplier</div><div class="ubbcode-body">reticle level?


edit to add: wait, what, there was no wind? how'd you survive in a vacuum? </div></div>

That sucks .
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KIDGLOCK</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: force_multiplier</div><div class="ubbcode-body">reticle level?


edit to add: wait, what, there was no wind? how'd you survive in a vacuum? </div></div>

That sucks . </div></div>

...wow quit your day job... you've got a new job ahead of you lol
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">Dude, people aren't kidding about testing your scope, making sure everything is square as well making sure you're not overly canting the rifle. More than likely you have a shit trigger press, but who can say without seeing it.

It is NOT SD and anyone telling you they are dialing SD inside 800m is more than likely dialing a piss poor trigger pull, or canting their rifle, or their equipment is not Square. It is not SD at 300, period ! </div></div>

Hmm it's a 2 pound trigger and I am squeezing it and letting it surprise me! My groups are Sub MOA at that range what should I check? My bi pod allows me to level the rifle. Both rifles are having the same point of impact!
 
Re: I need DOPE!!! Snipers please help

2 rifles... same thing... 1 shooter same results..... I think it's you buddy
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: (pink)MiST</div><div class="ubbcode-body">2 rifles... same thing... 1 shooter same results..... I think it's you buddy </div></div>


ohhh man! WTF! I don't get what I am doing wrong?
 
Re: I need DOPE!!! Snipers please help

A not square trigger pull that was consistant could move you that much easily. My problem is verticle at 300. I'll bet you are pulling the trigger back and to the left. By the way Low Light is the commandant trunk hooker in these parts.

good luck
Rthur
 
Re: I need DOPE!!! Snipers please help

Listen to LL. Practice the fundamentals as if your life depends on it. Once it's perfect I'm sure your problem will cease to exist. If in a month you're still having the same problem then have someone who knows what they're doing watch you shoot.

Also, what did you measure your wind speeds with? If it was just a rough estimation of very light wind speeds then there could've been something there but not enough for you to obviously notice it. And that could effect your groups enough with the 223. Doubtfull on the 30-06 but you never know.

Get back out there, shoot some more, and if you have the same EXACT results then you need help.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TerrorInTheShadows</div><div class="ubbcode-body">Listen to LL. Practice the fundamentals as if your life depends on it. Once it's perfect I'm sure your problem will cease to exist. If in a month you're still having the same problem then have someone who knows what they're doing watch you shoot.

Also, what did you measure your wind speeds with? If it was just a rough estimation of very light wind speeds then there could've been something there but not enough for you to obviously notice it. And that could effect your groups enough with the 223. Doubtfull on the 30-06 but you never know.

Get back out there, shoot some more, and if you have the same EXACT results then you need help. </div></div>

I ll shoot again and post my groups.
 
Re: I need DOPE!!! Snipers please help

See, I rest my case, now when you guys see me debating SD this is exactly what i am talking about. When people run out and say I am flat earther because I don't advocate this, everyone will know why.

With each retelling of the tale, it gets bigger, and more pronounced at shorter ranges every time.

Then the debate, I am great shot, it can't be me, no it has to be SD, the computer says so... my trigger light, my penis is large, my eyes are blue my hair is blonde, an Army Sniper talked to me in the airport. The list is endless.

1 MOA @ 300 yards, think about that... in class we have heard people go as high as saying they dial 2 MOA of SD @ 1000 yards, and now you get my point as it is playing out here right now.

This is exactly why I ask Bryan to make the caveats in BOLD... people latch onto one aspect of what is said, and suddenly the gospel is written. Oh, he has a right hand twist barrel, easy, SD...
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">See, I rest my case, now when you guys see me debating SD this is exactly what i am talking about. When people run out and say I am flat earther because I don't advocate this, everyone will know why.

With each retelling of the tale, it gets bigger, and more pronounced at shorter ranges every time.

Then the debate, I am great shot, it can't be me, no it has to be SD, the computer says so... my trigger light, my penis is large, my eyes are blue my hair is blonde, an Army Sniper talked to me in the airport. The list is endless.

1 MOA @ 300 yards, think about that... in class we have heard people go as high as saying they dial 2 MOA of SD @ 1000 yards, and now you get my point as it is playing out here right now.

This is exactly why I ask Bryan to make the caveats in BOLD... people latch onto one aspect of what is said, and suddenly the gospel is written. Oh, he has a right hand twist barrel, easy, SD... </div></div>


Hey hey hey Low light I might not be a great shot but damn it my penis is big!
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">See, I rest my case, now when you guys see me debating SD this is exactly what i am talking about. When people run out and say I am flat earther because I don't advocate this, everyone will know why.

With each retelling of the tale, it gets bigger, and more pronounced at shorter ranges every time.

Then the debate, I am great shot, it can't be me, no it has to be SD, the computer says so... my trigger light, my penis is large, my eyes are blue my hair is blonde, an Army Sniper talked to me in the airport. The list is endless.

1 MOA @ 300 yards, think about that... in class we have heard people go as high as saying they dial 2 MOA of SD @ 1000 yards, and now you get my point as it is playing out here right now.

This is exactly why I ask Bryan to make the caveats in BOLD... people latch onto one aspect of what is said, and suddenly the gospel is written. Oh, he has a right hand twist barrel, easy, SD... </div></div>


Hey hey hey Low light I might not be a great shot but damn it my penis is big! </div></div>

.... Face palm....
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: (pink)MiST</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">See, I rest my case, now when you guys see me debating SD this is exactly what i am talking about. When people run out and say I am flat earther because I don't advocate this, everyone will know why.

With each retelling of the tale, it gets bigger, and more pronounced at shorter ranges every time.

Then the debate, I am great shot, it can't be me, no it has to be SD, the computer says so... my trigger light, my penis is large, my eyes are blue my hair is blonde, an Army Sniper talked to me in the airport. The list is endless.

1 MOA @ 300 yards, think about that... in class we have heard people go as high as saying they dial 2 MOA of SD @ 1000 yards, and now you get my point as it is playing out here right now.

This is exactly why I ask Bryan to make the caveats in BOLD... people latch onto one aspect of what is said, and suddenly the gospel is written. Oh, he has a right hand twist barrel, easy, SD... </div></div>


Hey hey hey Low light I might not be a great shot but damn it my penis is big! </div></div>

.... Face palm.... </div></div>

lol what ever, I was just told I can shoot I have to have something.. so a big penis is all I have left well kind of big... well if I was Chinese I would be hung
 
Re: I need DOPE!!! Snipers please help

Clearly either the rifle is canted, or the reticle in relation to the rifle.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bm11</div><div class="ubbcode-body">Clearly either the rifle is canted, or the reticle in relation to the rifle. </div></div>

read here, and understand.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2330680&page=1

actually, you dont even have to read, just look at the target pic and it should click.

I had a similar issue before realizing that I was continually pushing the rifle slightly to the right while I was trying to get a proper cheek weld. Once I corrected and my shooting position became more muscle memory Its not really an issue any more. But it took a little while of double checking myself. If I'm working with quality gear that is obviously functioning, I always assume the fault lies with the human factor. Even if that means swallowing a little pride and admitting that I'm f**king up.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nly205</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bm11</div><div class="ubbcode-body">Clearly either the rifle is canted, or the reticle in relation to the rifle. </div></div>

read here, and understand.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2330680&page=1

actually, you dont even have to read, just look at the target pic and it should click.

I had a similar issue before realizing that I was continually pushing the rifle slightly to the right while I was trying to get a proper cheek weld. Once I corrected and my shooting position became more muscle memory Its not really an issue any more. But it took a little while of double checking myself. If I'm working with quality gear that is obviously functioning, I always assume the fault lies with the human factor. Even if that means swallowing a little pride and admitting that I'm f**king up. </div></div>

Wow! I see what you guys are talking about! So I need to line up straight on with the rifle? I was told to be sprawled a little to the left of the rifle is that right?
 
Re: I need DOPE!!! Snipers please help

allow me to quote someone more credible than myself

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">



You need to be straight behind the rifle for a host of reasons easier to show than explain in writing.

Weapon pointed to the target, body pointed to the weapon.

As well you apply a bit of forward pressure with the toes before dropping and relaxing your lower body. It's about management recoil and if you cock your body an anyway you give the recoil some place other than straight back to gone, which in turn throws the rifle off after the shot. </div></div>

While the body angle is a base fundamental, and it needs to be maintained, the rifle/scope cant will affect your POI in the manner your having issues with.
 
Re: I need DOPE!!! Snipers please help

Where's my pop corn.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">Spin Drift is a Bitch... not only will she divorce you, take your money, eat your dog, but she'll also fuck your best friend.

Good luck with that... </div></div>

I damn near pissed my pants. That's why my wife has been acting strange.
 
Re: I need DOPE!!! Snipers please help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: camomallninja</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nly205</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bm11</div><div class="ubbcode-body">Clearly either the rifle is canted, or the reticle in relation to the rifle. </div></div>

read here, and understand.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2330680&page=1

actually, you dont even have to read, just look at the target pic and it should click.

I had a similar issue before realizing that I was continually pushing the rifle slightly to the right while I was trying to get a proper cheek weld. Once I corrected and my shooting position became more muscle memory Its not really an issue any more. But it took a little while of double checking myself. If I'm working with quality gear that is obviously functioning, I always assume the fault lies with the human factor. Even if that means swallowing a little pride and admitting that I'm f**king up. </div></div>

Wow! I see what you guys are talking about! So I need to line up straight on with the rifle? I was told to be sprawled a little to the left of the rifle is that right? </div></div>

? yes, but thats really not what that thread was about. . .
 
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