i have been confused to no end on MOA and the references. i understand the 1MOA is 1" @100yds and so on. now, does that mean that if you are sighted in at 200yds, the MOA for a 400yd shot would be 2MOA? or because it is at 400yds, it would be the 4MOA? and is there any data sheets that have a generalized MOA calculation for distance?
regarding MOA
1 - 20 of 22 Posts
Joined
·
604 Posts
OK, fair question. 1 minute of angle is 1" at 100 yards ... 1 minute of angle is 4" at 400 yards. 3" @ 300 yards and so on. A weapon that will shoot into 1 minute of angle at 100 yards should theoretically shoot 2" at 200 yards, 3" at 300 yards. Theoretically! We all wish it were always so.
OK, Guys - let's keep this simple. No need to confuse the issue with getting into the grass hairs of One Minute Angle. Just assume 1MOA is equal to 1.0".
Comvet - Welcome to the board. Main rule is to play nice with others and respect all postings. If you will do an Archives search on the board, you'll find lots of previous discussion on this issue. In fact, merely scroll down to the bottom of this page and under "Similar threads", click on the listed threads regarding MOA.
Comvet - Welcome to the board. Main rule is to play nice with others and respect all postings. If you will do an Archives search on the board, you'll find lots of previous discussion on this issue. In fact, merely scroll down to the bottom of this page and under "Similar threads", click on the listed threads regarding MOA.
thanks kdub. im also printing out and doing some research on the army FM covering their sniper training, hopefully that will help out some too. im currently deployed and hoping to go sniper. just thought i could use the sniper training and MOA to help with hunting too.
Joined
·
14,097 Posts
Comvet25,
What has been said is correct, but perhaps did not addressing the root of your question? An moa is not a measure of distance across your target, it is a measure of angle. It is 1/60th of a degree. If you draw that angle on the ground at the range, with the two sides coming to a point (the apex of the angle) right at the rifle scope, you will see the sides of that 1/60 degree angle (or any other angle) grow farther apart the further you go forward from the apex. With an angle that small, at 100 yards the sides will be just over an inch apart. By the time you've gone 200 yards from the scope, they will be just over two inches apart. Indeed for every additional 100 yards you go forward from the scope, they will be just over another inch apart.
When you think about gun sight adjustments, you will realize all they do is adjust the angle between the centerline of the barrel bore and the line of sight looking through the sights (the sight line). Since the manufacturer has no idea what distance you will be shooting at, he can't offer the adjustment in inches of change in point of bullet impact at the target. That is why the adjustments are expressed as the angle between the sight line and bore that they adjust. It is up to the shooter to know the range he is shooting at the target from, so he can figure out how much a change in angle with the sight adjustments will move the point of impact of the bullet.
It's not hard. Use the approximation that 1 moa will move the bullet 1 inch for every hundred yards of distance.
What has been said is correct, but perhaps did not addressing the root of your question? An moa is not a measure of distance across your target, it is a measure of angle. It is 1/60th of a degree. If you draw that angle on the ground at the range, with the two sides coming to a point (the apex of the angle) right at the rifle scope, you will see the sides of that 1/60 degree angle (or any other angle) grow farther apart the further you go forward from the apex. With an angle that small, at 100 yards the sides will be just over an inch apart. By the time you've gone 200 yards from the scope, they will be just over two inches apart. Indeed for every additional 100 yards you go forward from the scope, they will be just over another inch apart.
When you think about gun sight adjustments, you will realize all they do is adjust the angle between the centerline of the barrel bore and the line of sight looking through the sights (the sight line). Since the manufacturer has no idea what distance you will be shooting at, he can't offer the adjustment in inches of change in point of bullet impact at the target. That is why the adjustments are expressed as the angle between the sight line and bore that they adjust. It is up to the shooter to know the range he is shooting at the target from, so he can figure out how much a change in angle with the sight adjustments will move the point of impact of the bullet.
It's not hard. Use the approximation that 1 moa will move the bullet 1 inch for every hundred yards of distance.
Joined
·
39 Posts
moa
as allready stated a 1" group at 100 yards is equal to 1 moa. thereby a 1 moa group at 50yards is half an inch across .and a 1 moa group at 200 yards is 2" across.
All you need to do is be aware that if your rifle is capable of shooting 5 shots measured centre to centre at 100 yards into 2" it is a 2 moa rifle. Its normal group size at 1000 yards is within a 20 " circle. A 1/2 Moa gun ,s group will be within a 5" circle
Trajectory is the curve from the barrell to the target. The factors that determine this are 1..The weight of the bullet/projectile 2.. The speed ( muzzle velocity of the bullet0. 3 The shape of the bullet be it a round ball , boat tail spire point etc. This is commonly expressed
as the BC.. ballistic coefficient of the bullet.( How well it flies. think basketball vs football.)
4 The distance you want the rifle to hit dead on say 225 for a 308, if you sight it for 300 the rise above the line of bore will increase .
The old military ladder sights make this easier to understand as the soldier estimated the enemys range and raised the back sight for longer distances thus increasing the angle of elevation of the barrell , so the bullet went higher to come down at the target like throwing a baseball .
These are the basics. speed can be affected by case capacity, powder type and burning rate .
effecient design of case , lenght of barrell ,twist of barrell etc.
Find a ballistics program ( Remington sell one on their web site) and then understand that long range shooting is a black art..
Oh and dont forget to look up windage, mirage ,mil dot scopes ,wind indicators ,breathing and people shooting back.
In basic terms target shooters will refer to the size of a group ( usually measured from the centre of the bullet hole 0n one side of the group to the centre of the hole farthest from it in terms of moa
as allready stated a 1" group at 100 yards is equal to 1 moa. thereby a 1 moa group at 50yards is half an inch across .and a 1 moa group at 200 yards is 2" across.
All you need to do is be aware that if your rifle is capable of shooting 5 shots measured centre to centre at 100 yards into 2" it is a 2 moa rifle. Its normal group size at 1000 yards is within a 20 " circle. A 1/2 Moa gun ,s group will be within a 5" circle
Trajectory is the curve from the barrell to the target. The factors that determine this are 1..The weight of the bullet/projectile 2.. The speed ( muzzle velocity of the bullet0. 3 The shape of the bullet be it a round ball , boat tail spire point etc. This is commonly expressed
as the BC.. ballistic coefficient of the bullet.( How well it flies. think basketball vs football.)
4 The distance you want the rifle to hit dead on say 225 for a 308, if you sight it for 300 the rise above the line of bore will increase .
The old military ladder sights make this easier to understand as the soldier estimated the enemys range and raised the back sight for longer distances thus increasing the angle of elevation of the barrell , so the bullet went higher to come down at the target like throwing a baseball .
These are the basics. speed can be affected by case capacity, powder type and burning rate .
effecient design of case , lenght of barrell ,twist of barrell etc.
Find a ballistics program ( Remington sell one on their web site) and then understand that long range shooting is a black art..
Oh and dont forget to look up windage, mirage ,mil dot scopes ,wind indicators ,breathing and people shooting back.
That depends on what you're shooting. A .22 LR will drop far more than a .308 Winchester at 200 yards. Yes, you can find ballistic charts for bullet drop. Just search your caliber on google and I'm sure you'll find a lot of information. What you're looking for is "x inch drop at y yards". You can print off that information and start to remember it. Now, knowing that 1 MOA is simply 1 inch for everyone hundred yards (close enough!) you can adjust your sight in MOA. Some sights use quarter MOA clicks. So if your sight is zeroed for 100 yards but you're taking a longer shot, say 400 yards, you consult your ballistic chart (see how much that bullet is going to drop) and dope your scope.
I'm not sure if that helps, but I read through the thread and it seemed like that might be what you needed to hear.
Joined
·
123 Posts
Joined
·
2,613 Posts
comvet25,
IM me if you have additionial questions. I'm retired Army and qualified sniper still down range.
CD
IM me if you have additionial questions. I'm retired Army and qualified sniper still down range.
CD
Joined
·
604 Posts
Combat Diver: AND Special Forces? I'm impressed Soldier. De Oppresso Liber.
Joined
·
409 Posts
I second that.
Combat Diver: i would gratefully take any help that can be offered. my road to becoming a sniper is probably fairly long, however, taking a clean, humane kill of a deer or elk is more within my grasp now. i dont wanna be "that guy" who puts a bad shot on one and it is simply wounded.
thanks for all of the help and input from everyone. i just ordered my scope and mounting base yesterday. now im doing the research and trying to get a head start on understanding the MIL-DOT system. that is kinda confusing too. im just "assuming" that MOA and the MIL-DOT may be a deadly combination for shooting once i get both of them down pat.
Joined
·
2,613 Posts
MIL-DOT scopes use MOA(60min) not MILs (6400) for reference between dots. Comvet25, I sent you a PM (look at the top right hand of your screen, under your log in) and an email. If you can get John Plaster book on "Ultimate Sniper" answers allot of your questions. TMs coming later.
CD
ETA: 1000 post-
CD
ETA: 1000 post-
1 - 20 of 22 Posts
Join the discussion
