question for the long-range shooters....new pics added......

Dog_Sniper

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I got a 223 with 55 grain 243 with 55 grain in a 243 with 100 grain I'll shoot half moa out to around 400 yards at 5 it widens and 6 it goes to crap everything shoots left pardon me everything shoots right and low and the lighter the bullet the more right and the more low is there an explanation for this or am I just a terrible shot any help or comments would be greatly appreciated
 
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20 inch sporter on the 243 barrel 22 inch heavy onthe 223. everything out to 400 is dead on I put in the adjustments for the further ranges and it seems like something just goes to crap I assume it's me but I'm hoping there's a factor but I'm just overlookingwith a backstop and walking it on I could hit the 10 inch steel 3 times out of 4 with 100 grain 243 never did hit it what the 223 until I moved up to 400 yard mark but then I could group it darn near touching
 
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Right hand twist barrel will tend to drift bullets to the right.The low part is just a function of the distance.Bullets drop at distance.
 
It's funny,,,Over the years I've heard a lot of theories about bullet drift and some of the various reasons for it to happen...High vs Low Humidity, High vs Low Elevation, etc...and while I could never say that any of it is not true, I really question the predictability of the claims...

There is a group in Texas (Houston Area, I believe) that I've read about that are chasing the five shot, one hole situation and have set up a range inside an old warehouse that has perfect lighting, the total absence of wind movement and extra stability built into the shooting benches and are still chasing that dream...

Just as the movement of the earth will have an effect on trajectory at a given distance, I'm reasonably sure that there are other factors that can affect a point of impact, the problem is identifying the factor to the point that one can predict the precise amount of movement that is applied at any given distance and at what speed...Movement of 1/4" or 1/8" at 100 yards is so minute that assigning a causal factor is almost impossible to the point that the shooter can predict the outcome in advance...
 
I think if your having trouble past 400 yrds your velocity is off on whatever ballistic program you're using. It has always seemed to me that 400 yards was the magical distance. You could be off on your velocity or b.c. a little and still be pretty close at 400 but past that if either are incorrect trajectory would be off and only get worse the farther you go. How did you come up with your velocity because if I go off what a chrono tells me my trajectory is always off. To come up with my actual velocity I always shoot at various distances then adjust my velocity on my ballistics program until it lines up. As far as the shooting right issue there didn't happen to be a slight breeze did there because unless you are using high b.c. bullets beyond 400yrds even a tiny breeze will start to really affect your bullets drift.
 
Originally Posted By: Jabey9210I think if your having trouble past 400 yrds your velocity is off on whatever ballistic program you're using. It has always seemed to me that 400 yards was the magical distance. You could be off on your velocity or b.c. a little and still be pretty close at 400 but past that if either are incorrect trajectory would be off and only get worse the farther you go. How did you come up with your velocity because if I go off what a chrono tells me my trajectory is always off. To come up with my actual velocity I always shoot at various distances then adjust my velocity on my ballistics program until it lines up. As far as the shooting right issue there didn't happen to be a slight breeze did there because unless you are using high b.c. bullets beyond 400yrds even a tiny breeze will start to really affect your bullets drift. strong wind that day but it was dead in my face. And i shot a 5 shot stri g and too the avg on my chrono. Guess i still got some work to do. Thanks for replying everyone.
 
Originally Posted By: Jabey9210 How did you come up with your velocity because if I go off what a chrono tells me my trajectory is always off. To come up with my actual velocity I always shoot at various distances then adjust my velocity on my ballistics program until it lines up.

That method works for me too.
You can also get a data book of some sort and keep notes on your settings at different yardages.
Elevation is the easier part of the game to figure out. Dealing with wind will always be a struggle.
 
For me the vector (magnitude and direction) seems to be harder to adjust for past 400 yards. I believe time of flight becomes more critical in figuring points of impact and slight angles of wind really throw the calculations off "tables". Past 500 yards start adding spin drift and Corvallis effect and the fact that most of us wish we could shoot more often than we actually do. Keep records of every shot and see if your poi become more predictable. All of this is mute if your scope is not mounted level to the bore/action and the rifle fired when level.
 
Originally Posted By: spotstalkshoot. All of this is mute if your scope is not mounted level to the bore/action and the rifle fired when level.



Im really not trying to sound like a dummby. I have a 20 moa base and assumed when i mounted rings and scope that it was stright and true with the world. My retical was as level as the neighbors picket fence both vert and hori....off a sand bag and the coffee table. Its and old family method lol. Do you have a method of mounting that youd be interested in sharing? You know.....for us low tech, low cash fellas.
 
Originally Posted By: Dog_Sniper Do you have a method of mounting that youd be interested in sharing? You know.....for us low tech, low cash fellas.

Try using feeler gauges between the bottom of the scope turret housing and the 20 MOA base.
 
sounds as though the reticle is canted to some degree. That makes for the right/left dispersion. The human eye can't fully tell if the reticle is off only a few degrees. I still havn't found a fool proof way of getting the rifle and scope perfectly aligned. Even if you do, and your rifle is only a few degrees canted in the bags/rest, that will cause right and left errors over distance. Under recoil, the rifle also torques in the direction of the rifling i.e. (right hand twist = right hand torque)

For the Drop variance, I do not adjust the MV in the chart, as that number is a "known" variable since the avg of a 5 shot string across the chronograph provides that information. Remember when shooting to get that average, to wait several minutes between shots, so that there is no residual heat in the chamber, which will raise pressures due to heating the powder in the case to a degree, while you are aiming/breathing etc before each shot. I run the chart using the manufacturer's BC rating and the MV from the chrono. Then I go and shoot at the increasing distances while measuring the drop and comparing that to the drop on the chart. When they vary, I adjust the BC and re-run the chart until the real world drop matches (as closely as possible) the drop on the chart. The BC is the "unknown" variable in the equation. The BC from the manufacturer is akin to the MSRP on a product,..it isn't necessarily what you will find when you actually go to the store.

at least that's my take on it
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Originally Posted By: spotstalkshootFor me the vector (magnitude and direction) seems to be harder to adjust for past 400 yards. I believe time of flight becomes more critical in figuring points of impact and slight angles of wind really throw the calculations off "tables". Past 500 yards start adding spin drift and Corvallis effect and the fact that most of us wish we could shoot more often than we actually do. Keep records of every shot and see if your poi become more predictable. All of this is mute if your scope is not mounted level to the bore/action and the rifle fired when level.

You do not get "Spin drift", or "Corvallis" (???) effects at 500 yds, or even at 700/800 with these cartridges - those are very long range problems and you are not dealing with that here.

*(Whatthehell is Corvallis???
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This kindle has a weird spell check coriolis, ref for the long range. Dog sniper level your rifle in a vise and remove turret caps and check scope for level. You can remove the bolt from bolt actions and use a piece of bar stock to set the level on. Ar use the rail to set level position.
 
Originally Posted By: CatShooter

*(Whatthehell is Corvallis???
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It was a little compact car produced by General Motors between the years of 1959 and 1969.
 
Originally Posted By: fw707Originally Posted By: CatShooter

*(Whatthehell is Corvallis???
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It was a little compact car produced by General Motors between the years of 1959 and 1969.

I think "69" was it's best year
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