AR Sponsor
Posted: 1/4/2013 9:53:40 AM EDT
| Hey guys, I've got a SIG 516 that's giving me some pretty weird results. It functions flawlessly, but the trajectory sucks. It's level at about 25 yards, but then around 2 feet high at 125 yards. I'm using Federal 5.56x45 55g NATO stamped. My barrel is a 1/7 twist, is it the ammo I'm using? Does anyone else have this problem? |
|
not bashing and i love my Sig516, try zeroing with the irons, but the Sig red dots have had less than stellar reports, i ended up putting a T1 on mine. this is just me, but i would verify zero with irons, and try a different red dot. see if a friend can let you borrow a red dot and see what kind of groups you can get.
|
|
Quoted:
Hey guys, I've got a SIG 516 that's giving me some pretty weird results. It functions flawlessly, but the trajectory sucks. It's level at about 25 yards, but then around 2 feet high at 125 yards. I'm using Federal 5.56x45 55g NATO stamped. My barrel is a 1/7 twist, is it the ammo I'm using? Does anyone else have this problem? Your title is quite misleading. You don't have a problem with the gun, you have a problem with the user. First thing you need to know is the yardage you want it to be sighted in. The 25 yard sight in is just to get it on the paper at your actual sight in distance. Since you have it on the paper now you are ready to sight it in at your actual sight in distance. #1 Place a target at your preferred distance. (200-250 yards is good with a dot or irons) #2 Shoot bullets at target and adjust your sighting device to put it on the bulls eye. If you don't have a place to shoot 250 yards you can just sight it in a couple of inches high at 100 yards, or 125 yards, whatever. I am sure it will be close enough for you to learn basic techniques. |
| This is the only rifle I've ever had problems with. I sight in every gun that way, including my M14 and it's always spot on. 25 yards is supposed to be when the bullet is level, then it levels back out at somewhere around 150 yards. The point is, the gun is messed up or my ammo hates me gun. Not a user error. |
|
This is the only rifle I've ever had problems with. I sight in every gun that way, including my M14 and it's always spot on. 25 yards is supposed to be when the bullet is level, then it levels back out at somewhere around 150 yards. The point is, the gun is messed up or my ammo hates me gun. Not a user error.
Yes, definitely user error. 25 yards is not the right distance to zero that rifle for a 150 yard zero. Stupidity can't alter the laws of physics no matter how hard you try. Zero it at 50 yards and then come back and tell us your results. |
| Wow, so many opinions. With most 5.56 ammo, a 50 yard zero will provide the least amount of deviation from the target out to about 300 yards. Depending on your bore to sight axis, less than 50 yards rounds will be from 0 to 2 inches low. They will be high between 50 and 200 and then low after 200. This has proven to be the best combat zero for irons and un-magnified red dots. |
|
Wow, so many opinions. With most 5.56 ammo, a 50 yard zero will provide the least amount of deviation from the target out to about 300 yards.
Yes. A 25 yard zero with standard height AR-15 sights will put the bullet ridiculously high at the mid point which is exactly what the OP is getting. This is not rocket science. |
| @wildnfree, no point in being a dick. I'm doing what SIG told me to do. The problem is most likely the ammo. SIG told me that if I'm using 55 grain ammo then I need to move the sight up about an inch at 25 yards. They said the gun IS SUPPOSED TO BE SIGHTED IN AT THIS RANGE AND LEVEL OUT AT 125. They said 62 grain shouldn't have this problem. All I have to do is wait on some ammo and test both weights. |
|
@wildnfree, no point in being a dick. I'm doing what SIG told me to do. The problem is most likely the ammo. SIG told me that if I'm using 55 grain ammo then I need to move the sight up about an inch at 25 yards. They said the gun IS SUPPOSED TO BE SIGHTED IN AT THIS RANGE AND LEVEL OUT AT 125. They said 62 grain shouldn't have this problem. All I have to do is wait on some ammo and test both weights.
Me being a dick? LOL. Sig is wrong and you will remain at the special education level of intelligence regarding the ballistics characteristics of the 223/556 round as long as you listen to them instead of the experienced people on this forum. The problem is most definitely not the ammo or your rifle. There is virtually no practical difference between the trajectory of 55 gr and 62 gr ammo out to 250 yards. Why do you need to test 'both' when you have already tested one and instead of getting the results you expected you got the results we said you would, and told you what the problem is. But you are so hard headed that you won't even correct your problem with the correct advice that we gave you, and you are still trying to blame your problem on your rifle or ammo. IF you actually knew anything about sighting in a rifle you would know that what the bullet is doing at 25 yards (or 50 yards) doesn't mean squat anyway when the target you really need to be able to hit is at 200/300/400 yards. If you sight it in to hit your target at the longer range you will be right on track at the closer distances. Have you ever heard of 'point blank range'? Here is a link for you to play with if you are interested. The figures on the chart are what you should get with a 50 yard zero. The PBR figures can be pulled up by setting the correct parameter in the box if you had rather sight in that way. Just click the calculate button at the bottom of the page when you get to the link. http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.1.cgi I also have my doubts about your measurements. If you actually did sight in your AR at 25 yards the bullets will not be hitting over 12 inches high at 125 yards. Did you actually measure this distance or just make a wild ass guess? For the bullet to hit 12 inches high at 125 yards would require a 20 yard sight in distance (zero). They said the gun IS SUPPOSED TO BE SIGHTED IN AT THIS RANGE AND LEVEL OUT AT 125
Once again, Sig is wrong. Sig builds guns. The people on this forum shoot them. IF you use a 25 yard zero it won"t level out till it reaches approximately 225 yards at which point it will be approximately 9 inches above the line of sight, and then it will cross the line of sight again (zero) at around 400 yards. To get it to level out at anywhere close to 125 yards would require a zero of around 50 yards (225 yards). I also noticed your previous post said that it levels out at 25 yards and then levels out again at 125 yards. Wrong. A bullet only levels out once at the very brief instant it reaches it highest trajectory. Also, just because you always use a 25 yard zero on all your guns, including your "M14" and it has always worked fine just shows you how lucky you have been in the past, but your luck has run out. If you will study the charts provided above in this thread and at the link maybe you will understand what we are trying to tell you. |
|
Go to page 50 of FM23-9 and read and understand. Look at the pictures. A 25 yard zero is for iron sights, specifically the LONG RANGE reticle.
Do you see in the quote below where it says: " After making this adjustment and flipping back to the short-range sight and aiming center of mass at a 42-meter target, the bullet crosses the line of sight at 42 meters and again at 250 meters as shown in Figure 3-22." This is the result you want with your RDS since YOU DON'T HAVE A LONG RANGE FLIP UP RETICLE IN YOUR RDS for long range sighting. Also, they are sighting in at meters. Since you are using yards you will need to convert meters to yards so you would end up with a zero range of 42 meters plus 4.2 which equals 46.2 yards short range and 250 meters plus 25 or 275 yards long range." Read this from page 51 and understand. Convert meters to yards to get correct distance. Most combat targets are expected to be engaged in the ranges from 0 to 300 meters; therefore, the 250-meter
battlesight zero is the setting that remains on the rifle. At 25 meters, the bullet is about I inch below line of sight, crossing line of sight at 42 meters. It reaches its highest point above the line of sight (about 5 inches) at a range of about 175 meters, crosses line of sight again at 250 meters, and is about 7 inches below line of sight at 300 meters. Targets can be hit out to a range of 300 meters with no adjustments to point of aim. (A somewhat higher hit probability results with minor adjustments to the aiming point.) Notice they say to aim 1" low at 25 meters. This puts your zero at approximately 46 yards. [This is also the same Point Blank Range sighting method I was talking about in my previous post]. M16Al STANDARD SIGHTS AND ZEROING
To battlesight zero the rifle, the soldier must understand sight adjustment procedures. The best possible zero is obtained by zeroing at actual range. Because facilities normally do not exist for zeroing at 250 meters, most zeroing is conducted at 25 meters. By pushing the rear sight forward so the L is exposed, the bullet crosses line of sight at 25 meters, reaches a maximum height above line of sight of about 11 inches at 225 meters, and crosses line of sight again at 375 meters (Figure 3-21). To gain the many benefits associated with having bullets hit exactly where the rifle is aimed during 25-meter firing, the long-range sight is used on the zero range. Therefore, when bullets are adjusted to bit the same place the rifle is aimed at 25 meters, the bullet also bits where the rifle is aimed at 375 meters. After making this adjustment and flipping back to the short-range sight and aiming center of mass at a 42-meter target, the bullet crosses the line of sight at 42 meters and again at 250 meters as shown in Figure 3-22. A person with a closed mind repeats the same mistake over and over and wonders why he doesn't get a different result. |
|
On my Sig 516, I did the 25/50 yard zero. This is the target you place at 25 yards with a green bulls-eye dead center and another grey bulls-eye about an inch or so lower than the green one. You aim at the green bull-eye and adjust until your impacts are in the grey one. This target effectively nets you a 50/200 yard zero which has the smallest amount of overall deviation in trajectory from 25 to 300 yards. With this method, I have not experienced any of the issues you have reported. Try it and report back.
Here is the target: 
http://www.ar15.com/mobile/topic.html?b=3&f=18&t=529846 Here is a great PDF on the subject: http://gunwebsites.net/wp-content/uploads/2011/09/Guns-AR15-Zero-Introduction.pdf |
|
Quoted:
This is pretty much what I was hoping for, I'll try it when I get good ammo. I only have a handful of Wolf left. So as soon as I can find some federal ill get it the.n try it with this target. Thanks! You don't need good ammo to confirm whether or not this works. Once you do the 25 yard zero, you will only need about three shots at the longer distances you mentioned earlier to confirm whether or not this worked for you. I used TulAmmo. Sure, better ammo will be more accurate and precise, but you were so far off the mark that if you start hitting paper at longer ranges with the cheap stuff, that should be all the evidence you need to come to the conclusion that the Sig recommended 25 yard zero was a bad recommendation. |
|
Quoted:
On my Sig 516, I did the 25/50 yard zero. This is the target you place at 25 yards with a green bulls-eye dead center and another grey bulls-eye about an inch or so lower than the green one. You aim at the green bull-eye and adjust until your impacts are in the grey one. This target effectively nets you a 50/200 yard zero which has the smallest amount of overall deviation in trajectory from 25 to 300 yards. With this method, I have not experience any of the issues you have reported. Try it and report back. Here is the target: http://farm8.staticflickr.com/7035/6642425017_852909d97f_o.jpg http://www.ar15.com/mobile/topic.html?b=3&f=18&t=529846 Here is a great PDF on the subject: http://gunwebsites.net/wp-content/uploads/2011/09/Guns-AR15-Zero-Introduction.pdf This. |
|
The target fixed it.
LOL. "IT" wasn't broke, so the target didn't fix "it". All the target did was put 'your' problem in simple enough terms for you to understand so 'you' could turn the little screws to fix 'your' problem. But I am glad you finally figured it out. |
|
Quoted:
Wow, so many opinions. With most 5.56 ammo, a 50 yard zero will provide the least amount of deviation from the target out to about 300 yards. Depending on your bore to sight axis, less than 50 yards rounds will be from 0 to 2 inches low. They will be high between 50 and 200 and then low after 200. This has proven to be the best combat zero for irons and un-magnified red dots. You've seen combat with that zero? Zen of the 100 yard Zero by this guy who puts on a hell of a carbine class. |
AR Sponsor