Need help understanding my rifle at 500yd

The Revenge

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Hey gang.
Recently got my first bolt guns and started shooting at increased distances.
Went to a precision rifle course a weekend or two ago. The new to me rifle I brought to the cousre is a savage model 10pc 308 5r 20" barrel. I used federal Sierra match king bthp 168gr. Vortex pst 4-16 Ffp scope. I broke the barrel in and zero'd the rifle before going to the class.
The first day we only shot to 100yd learning and doing different drills and practice. All was well. Rifle very accurate. They had us rapidly engaging eggs. They even put two 308 casings on a ledge to see if any of us could hit one. I hit one.
Next day we moved from 100yd out to 500yd, stopping at 200,300 and 400 along the way.
All shots were done using holdovers. 200 right on. 300 right on. 400 right on. Sub moa shot groups the whole way.
At 500 I ran into a problem. According to the instructor my holdover should have been right at 12moa at 500yd. Even on my isnipe app it shows the holdover as 11.67 moa.
I couldn't hit the target which was a 10" metal plate. There was a spotter and he kept calling my shots low. I finally hit the target with my holdover at 14 moa.
A day or two later I went to a local range and used a chrono. The rounds were averaging 2600 fps, only 50fps slower than advertised for the ammo.
Anyone have any ideas why so much more holdover all of a sudden at 500yd? Is this just normal and every rifles different? I just wonder if this situation will be compounded now going beyond 500yd.
Thanks
 

seanhagerty

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My First thought would be did you laser range the 500 yd target? Next thought was about the wind, what was the wind doing when you engaged the 500 yd target?

I have found these two things to be what ails me the most when I am having difficulty with long range dope.
 

17874

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My 10PC has a 14 minute holdover at 500 meters with 168 GMM.
 

The Revenge

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My 10PC has a 14 minute holdover at 500 meters with 168 GMM.

Wow thanks. Did you just discover that on your own? Every ballistic chart and isnipe puts me at 12. So is this a situation where you go try those numbers and use them as a guideline?
The guy right next to me at the range had a R700 308 with 24" barrel and he was holding a hair under 12 and hitting the target. The guy on the other side of me was shooting a dpms LR308 and was holding closer to 11 to hit the target.
I was the only one way off at 14.
 

The Revenge

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Damn dude, just trying to help. Flame on

I don't know what that means. I took it as help. I thanked you for telling me your 10pc is at 14 also and basically asked if that was something you knew off the bat or through trial and error.
Then I added what the two shooters next to me were doing.
Sorry if I offended you somehow.
 

cmh2007

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every rifle is different in how fast or slow the barrel is. how high is your scope mounted above the barrel? what were the conditions? Is your scope tracking properly?

JBM is showing 13 MOA to 500 with that load.
 

The Revenge

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every rifle is different in how fast or slow the barrel is. how high is your scope mounted above the barrel? what were the conditions? Is your scope tracking properly?

JBM is showing 13 MOA to 500 with that load.

Thanks.
I used burris low mounts with a EGW base. I'm not sure where to take the exact measurement on scope height. I guesstimated at 1.5 inches for the sake of entering something in isnipe.
Conditions where 78 F with calm winds. They didn't show us any method to check tracking other than shooting at multiple targets, a whole days worth at 100yd. Then on the longer range the next day everything was to be done using holdover only. The first day everyone's zero's were verified.
I started logging everything at this class.
In terms of going further on the shots now, it's safe to say its trial and error? Dial in the scope for say 600 and just see where the shots go, then adjust from there?
I appreciate the feedback.
These are my first bolt guns and I'm having fun with them. I'm ex army but never touched a bolt rifle, I carried an M60.
 
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bodywerks

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Dial and see where it goes is one approach - an expensive one. If you don't reload and can blow money on sending $1.50 rounds into dirt until you get it right then continue on.
I started off that way but started reloading way early on so it didn't hurt too bad to waste my time.
What it takes to hit a piece of steel at 600 on a Sunday can be totally different from the following Friday. If you go to a range that's another 2000 feet higher than the range you went to last Sunday and its 15° hotter and you have a 7mph wind from your 8 o'cock, chances are if you just dial 14 MOA of up like you did last Sunday, chances are your first round down range is gonna be high and right.
If you want first shot cold bore hits at distance, a lot of reading and some data acquisition is in order...

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cmh2007

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well, you need to figure out the bore center line at the front ring...so take your calipers and figure out the diameter then divide by 2 the radius of the receiver, then you know the diameter of your scope. then figure up how thick your mount is and the height from the mount to the bottom of the scope tube. Mine is close to 1.65 so i just use 1.6 and it works out very close. as to figuring up your 600 yard dope, get onto JBM's site and work it there. as to tracking test, take it out and shoot a starting group then track it up say 6 or 8 inches, shoot a group then measure the grouping distances, or you can do a box test which will track you around the page and back to center to test return to center too.
 

RobertB

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No big deal if it's repeatable. I measure density altitude before and during each shooting session. Record all enviro data and what the rifle/load takes to get to a certain distance and what it as time goes to see what your getting. If it's not repeatable then somethings wrong. You are just getting info that's a little off but the info is getting you close. Use the data, get close, then make the necessary adjustment to get to certain range, record and repeat at later date. If you want to know for sure it takes rounds down range and doing it multiple times. Good luck
 

Sterling Shooter

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All,

In mid range HP competitions holding elevation effectively makes the target bigger and allows for some wind error without consequence. Holding elevation begins with an understanding for the trajectory of the bullet at any particular angle of departure, considering effects on the bullet from the primary factors of trajectory: gravity, drag, temperature, humidity, and wind. This knowledge is harnessed by properly maintaining a data or score book. For the most part, the score book will help the shooter understand what sight adjustment is necessary for any given target distance/condition.

In this thread, the OP wants to know why he did not hit the target. He did not hit the target because he did not properly adjust his sight for conditions, as well as distance. He perceived those who told him what to do knew how to do it. He assumed his instructors could interpolate the adjustment needed for the OP's rifle and ammunition. The OP's actions, made from his assumptions, did not produce the desired result. Now, the OP is here for answers when the easiest means to discover the source of his errors and the means to correct would be to record his observations in a score book, allowing for comparative analysis. Comparative analysis is ideal for coming to an understanding about trajectory or bullet path since we begin with an absolute that the trajectory is ALWAYS a definitive and uniform arc.
 
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bodywerks

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Yep. The only reason the OP was hitting the other targets at the closer distances was because the bullet trajectory was still rather flat. At 500 and only a 2500-2600fps, a 168gr bullet is on a decent downward trajectory, so what others were using as a dope wasn't 'close enough' anymore. Not terribly surprised it took 14MOA for that factory ammo out of a 20"barrel to get to 500

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The Revenge

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Thank you for all the feedback, I'll take all of it and apply it this weekend.
This weekend a near by range is having a scope a dope day out to 850yd.
I will also take my other new rifle a 300wm and give it a go.
 

bodywerks

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If you stick with that federal 168 your gonna most likely have a helluva time hitting targets at 850, especially at the velocities you're getting. You might want to stick with the 300wm for that distance.

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Sterling Shooter

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Thank you for all the feedback, I'll take all of it and apply it this weekend.
This weekend a near by range is having a scope a dope day out to 850yd.
I will also take my other new rifle a 300wm and give it a go.

Does your range have pit service? If it does not then you have little benefit, that's to say, your practice will not likely be a venue for progress. Instead, order a high power rifle score book, practice shooting at the MR-31 reduced course target, and plot your calls and strikes. Trouble shoot your shot errors from the likely source of error identified through the call/strike corollary. This sort of practice will get you off to a good start. You will get to where you'll be able to use triangulation to accurately determine your no wind zeros for any particular distance/condition, and a with the aid of a chronograph, you will be able to determine zero for any other particular distance your bullet can get to nose on.
 
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The Revenge

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Here's the event I'm going to.
https://docs.google.com/file/d/0B8pgXHKQNGRPZmJZWVRkdWdMUm8/edit?pli=1

It clearly states, please have adequate knowledge of your ballistics. Every ballistic I've pulled up for this rifle and round have been off at 500yd. It took 14 to hit the target, the closet ballistic program I've seen was 13. At this event if I try and hit the 600 or 700yd target should I just roll with the ballistic data and just compensate from there?
I have a Impact Data Book to record everything.
Thanks
 

bodywerks

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Its probably not the ballistics that's off. Its probably what you think the muzzle velocity is is off. Use the G7 BC in your ballistics program if it has the option and use the Litz version of that bullet if its in your bullet library. See what muzzle velocity you need to input to get a 14 MOA dial up and use that as your basis. I'm thinking that as the barrel warms up your only getting 2500-2550.
But like i mentioned before, good luck at 850 with the 168smk. There is tons of data that shows the bullet tends to become unstable near transonic.
Shooter shows 13.9 up at 500 with a 2500fps speed at 2000 density altitude, and transonic at 860.
If its way hotter and much higher density altitude you might get lucky, but a better billet with better ballistics would be a lot less frustrating...

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The Revenge

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When I enter those parameters in isnipe I get right at the 13.9 also. I'll use 2500 going forward. Would you have two dope cards in that case? One for hot barrel, one for cold? When I did the chrono the barrel was cold and the average was 2620 with that ammo.
I hear ya on the 850 with that ammo. With the 2500 number what would be the longest realistic target to stick with? This barrel is 11.25 and from what I've read the it handles the 175 better than the 168. The 168 was all I could find at the time.
The 300wm chrono'd at 3000fps cold. The box of ammo showed 2900. That rifle has a 24" thicker barrel. Would the same hold true with the drop in fps with that barrel? Or not as pronounced.
Thanks a ton.
 

bodywerks

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Different barrels act different with heat. Heavier, match barrels trend to stay more consistent.
On every savage i have ever owned, it would shoot high and erratic for the first 10 shots or so. After that it settled down and was quite consistent.
I'd say go with the one dope of around 2500 and know your first few shots will be a tad high.

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CEL317

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Another thing to consider is performing Brian Litz's "Tall Target Test" to confirm that when you are dialing 14 MOA on your turret that the reticle is actually changing your POI 14.658 inches at 100 yards.

The "Tall Target Test" is a highly valuable calibration exercise which gets you ready for long range shooting.
Simply place a 'tall target' at 100 yards or meters and draw a plump line (using a plumb bob or level). Fire a group at the bottom of the target at your zero, then dial the scope up 30 MOA or 10 MILS and shoot another group. Measure the distance between the two groups and determine how much the group actually moved in relation to the adjustment that was made on the scope.

image054.png


Copied from http://appliedballisticsllc.com/AB_app.htm
I highly recommend his book Accuracy and Precision for Long Range Shooting.

Of course if you can perform the test at any position up the turret. I did it in 5 MOA increments up to 30 MOA with mine. Again, it's just a suggestion/option.
 

turbo54

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My thoughts:

Forget the chrono. Who cares what it has to say? What matters is shots on target.

The **first** thing you need to do is ensure your scope tracks. That's first. Shame on your instructor(s) for not having you check this, if it was an introductory class.

Set up a 36" tall target at 50 yards with an aiming spot at the bottom. Fire 2 or 3 rounds at the spot, and then dial up 10 moa. Fire 2 or 3 more. Dial up another 10 and fire a few more. 30 MOA up from 100 yards will get you close to 1000 yards, the practical maximum range of your rifle. Measure your impacts and see if they jive. If not, you'll want to try some settings in between to find where it gets screwy.

Assuming the scope tracks, just keep practicing and collecting data. You'll have good dope before long.
 

Sterling Shooter

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Forget the chronograph? That's why the OP is struggling. With an understanding about average velocity, as well as S.D. and E.S., all of which can be made known from the chronograph, the shooter will have rounds on target without any drama. The chronograph is an essential tool for anyone serious about any sort of LR shooting. One more thing, while shooting at a tall target is ideal for zeroing to distances which are not available to the shooter while practicing, getting a result that puts the shooter exactly where desired is likely not possible. For example, when my match rifle with 1/4 minute sights is zeroed for 100 yards, 18 clicks will get me to 297 yards, while 19 clicks will get me to 315 yards from my average velocity of about 2650 fps at standard atmospheric conditions. If I was an ignorant shooter I might perceive that my scope does not track properly, not being able to get exact elevation for a 300 yard hit, rather than suspect it had something to do with the average velocity and my course fractional MOA adjustment increments not permitting me to precisely adjust to target distance.

At any rate, the OP would be wise not to forget the chronograph, the score book, and the spotting scope. These tools are all essential to the shooter who wants to master LR shooting. BTW, these tools have a big payoff for the guy shooting an as issued iron sight .223 Service Rifle in NRA LR. For such division, the shooter needs a very exact understanding for trajectory to aid the shooter's limited ability to hold elevation by appraisal of sight picture alone. Holding elevation by all means effectively makes the target bigger and allows for some wind error without point loss.

The previous poster suggested from a 100 yard zero you would need 30 MOA of adjustment to your sight to be on at 1000 yards. For your average velocity and bullet weight you have earlier indicated such an adjustment would not get you even close to 1000 yards. Your actual adjustment would be more likely in the neighborhood of 45 to 50 MOA. And even with a proper adjustment it's doubtful that your bullet would get to the target nose-on. It will likely begin to fly erratically and begin to tumble before it gets to the target.
 
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turbo54

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Sterling Shooter said:
Forget the chronograph? That's why the OP is struggling. With an understanding about average velocity, as well as S.D. and E.S., all of which can be made known from the chronograph, the shooter will have rounds on target without any drama. The chronograph is an essential tool for anyone serious about any sort of LR shooting.

Yes, foget the chrono, other than getting an initial idea of what kind of settings are required to get on target downrange. Case in point: The OP used a chrono, and then his his dope based on said chrono didn't work. What was it again the chrono did for him in this case?


Sterling Shooter said:
One more thing, while shooting at a tall target is ideal for zeroing to distances which are not available to the shooter while practicing, getting a result that puts the shooter exactly where desired is likely not possible. For example, when my match rifle with 1/4 minute sights is zeroed for 100 yards, 18 clicks will get me to 297 yards, while 19 clicks will get me to 315 yards from my average velocity of about 2650 fps at standard atmospheric conditions. If I was an ignorant shooter I might perceive that my scope does not track properly, not being able to get exact elevation for a 300 yard hit, rather than suspect it had something to do with the average velocity and my course fractional MOA adjustment increments not permitting me to precisely adjust to target distance.

You've said a lot here and honestly I don't really follow your point...

Are you suggesting that a full-range elevation tracking test of the sighting system is not warranted to ensure it actually adjusts what it says it does?? I hope not, because this is a fundamental aspect of LR shooting, and many of us (including myself) have experienced scopes that don't track - even with high dollar optics.

Or, are you suggesting that your chrono data is so good it allows you to resolve between 4.5moa (18 clicks) and 4.75moa (19 clicks) to achieve a perfect, dead-center shot at 300 yards?

Sterling Shooter said:
At any rate, the OP would be wise not to forget the chronograph, the score book, and the spotting scope. These tools are all essential to the shooter who wants to master LR shooting. BTW, these tools have a big payoff for the guy shooting an as issued iron sight .223 Service Rifle in NRA LR. For such division, the shooter needs a very exact understanding for trajectory to aid the shooter's limited ability to hold elevation by appraisal of sight picture alone. Holding elevation by all means effectively makes the target bigger and allows for some wind error without point loss.

We're going to have to go ahead and just disagree on how important the chrono is for tactical marksmen.

I'm with you 100% on a data book.

Sterling Shooter said:
The previous poster suggested from a 100 yard zero you would need 30 MOA of adjustment to your sight to be on at 1000 yards. For your average velocity and bullet weight you have earlier indicated such an adjustment would not get you even close to 1000 yards. Your actual adjustment would be more likely in the neighborhood of 45 to 50 MOA. And even with a proper adjustment it's doubtful that your bullet would get to the target nose-on. It will likely begin to fly erratically and begin to tumble before it gets to the target.

~35moa up from 100 generally gets a 308 to 1000 yards or close to it. You're splitting hairs. Obviously it depends on bullet, barrel length, velocity, density altitude etc etc etc etc. Hopefully the OP didn't take my "30moa will get you close to 1000 yards" as if I were Moses coming down from Mt. Sinai with his dope written on a stone tablet, because that's not what I meant - and I thought it was obvious. Forgive me for not being more clear.

Still, a scope tracking test from 0-30moa will indicate whether/not the optic is to blame for why it's taking the OP more dope to score hits at 500 yards than he thought, based on what the chrono had to say.

I have a chrono and I've used it quite a bit. It has never been the answer. It has generally gotten me close, but I'd NEVER EVER feel confident showing up to a shooting match with chrono-dope only. A databook plus hits on steel is what I'm confident in.

YMMV.
 

Sterling Shooter

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You stated the OP's come up from 100 to 1000 yards would be about 30 MOA. You were only off about 20 MOA. Following your advice the OP would not see progress. You don't know what you don't know about LR shooting and it shows. Following your advice is an example of the blind leading the blind. You don't have a clue about what's important to LR. Your advice is from what appears to be a very limited experience with the concept. Attempting to get good hits at LR requires knowledge of the trajectory produced by an angle of departure from an exact average velocity. You allude to the chronograph as not being needed. Only by using speculative methods for velocity recognition would it not be needed. And any of these alternative methods requires working math backwards from a ballistics table using the result created by zeroing from trial and error. The OP is now using the trial and error method working the math backwards and where has it taken him, no where. There is no substitute for the chronograph. Saying it is not needed and having such advice accepted by a novice shooter is a receipt for bad results which will thwart the aspiring shooter from reaching the highest plateaus of good shooting.

Oh one more thing, you probably missed it but the shooters here who actually do know something about LR told the OP that his bullet driven at its likely velocity envelope will not reach LR distances. So even if the sight was adjusted correctly it would be moot.
 
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The Revenge

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I appreciate everyone's advice.
In a nut shell here's where I'm at:
Went to precision course shooting out to 500yd.
Was shooting federal match 168 bthp. Hadn't used chrono at that point.
Used the ballistics from I snipe for that round, it used 2650fps.
100 very accurate, 200 using the isnipe holdover very accurate, same at 300yd, at 400 using the isnipe holdover rounds were landing 4-5 inches below bullseye, at 500yd using isnipe holdover of 12 I wasn't hitting target. Didn't until holding over 14.
Documented everything in my data book.
Came home the next day and used the chrono. Average out of 3 rounds was 2620. That was with a cold barrel, I didn't realize a hot barrel would or could have effected fps on the range the weekend before.

Now this weekend I'm going to another event with the chance to shoot out to 850.
Should I stick with the holdovers that were accurate out to 300 then apply the data from I snipe with a lower fps for targets beyond? When I enter 2520 in isnipe I get the 14 holdover for the 500 target.
Sterling what's the next step to avoid being blind? Just trying to learn to shoot better.
Thanks
 
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Sterling Shooter

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The tall target is a way of zeroing to known distance without having to actually shoot at such distance. I shoot in 1000 yard matches. These matches usually allow for unlimited sighters and 20 rounds for record in a 30 minute period. Knowing my 2800 fps average muzzle velocity for the 80 grain Berger .224 bullet I shoot will have a bullet path 36 inches high at 100 yards, for bullet path and line of sight to intersect at 1000 yards, I will adjust my sights for a result which will place the bullet 36 inches high at 100 yards. I shoot at the tall target to confirm the adjustment taken to the sights actually produces a triangulated zero 36 inches above point of aim at 100 yards. I may not initially get an exact result or an exact result may not be possible if I am not actually producing a velocity of 2800 fps. But in any event the result gives me confidence my first round will be somewhere inside the 10 ring on match day. This means I will not need to use time for sighters that could be useful for record shots. It also means less fatigue, and, if shots do not go on call, I can be more certain it was from a bad wind reading rather than from a bad no wind zero. BTW, having a first round hit in the 10 ring at 1000 rather than a shot somewhere off paper which needs to be somehow dialed in is a big help to remaining composed to attend to rebuilding the position for each shot at LR, instead of being distracted from position concentration by having to get on paper.
 

turbo54

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I have to wonder if sterling is reading the same thread I am...

The question: what is 2+2?

Sterling's answer: the refraction of light rays in atmospheric dust causes the sky to be blue

...a true statement in its own right, but has nothing to do with the question asked.

Revenge: for now, go with what you know works, based on actual observed trajectory. When you can, check your scopes tracking @ 50 yards on a tall target. That test won't tell you what dope you need, but WILL tell you if the scope is reacting to your inputs as expected.

I've had a very similar situation caused by a scope not adjusting as indicated on the turret.
 

Sterling Shooter

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OP,

The 3 shots you took to get average muzzle velocity of 2620 does not relate to my experience with a standard 168 grain load from the barrel length stated. The results you got indicating 14 MOA up for a good 500 yard hit from 100 yard zero would indicate 2500 fps as your average muzzle velocity. So something is wrong here. I'd suggest going back to the chronograph and shooting another string of fire. Or,if that's not possible, input 2500 fps with standard atmospheric conditions using JBM Ballistics Calculator. And see what the bullet path at 100 yards needs to be above line of sight for line of sight and bullet path to intersect at 860 yards. I think using such approach will better assure a first round hit if you counter properly for wind. Remember though, 860 yards is really pushing it for a 168 grain bullet at the sort of velocity you are likely getting from your barrel length. Once the bullet begins to destabilize it will fly erratically and tumble end over end. This is where marksmanship ends.

Another thought, the tall target is also useful to understand if the sight is squared to the rifle's receiver. If not square you will take some windage along with the ride to distant target.

One more thing, we have been talking about taking fractional MOA clicks on your sight. Is your sight graduated in fractional MOA, or in fractional inch increments? Confusion about what you've got could be worth about an MOA of error at the sort of distance you are shooting to. It's another good reason to shoot at the tall target at 100 yards.
 
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The Revenge

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What is your experience on muzzle velocity with that round and 20" barrel?
My scope is a vortex pst 4-16 with Ebr-1 moa reticle. It has .25 moa adjustments. The hash marks on the reticle are in 2 moa increments. We never dialed up our scopes that whole last event. We just used holdovers.
Thanks
 
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Sterling Shooter

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What is your experience on muzzle velocity with that round and 20" barrel?
My scope is a vortex pst 4-16 with Ebr-1 moa reticle. It has .25 moa adjustments. The hash marks on the reticle are in 2 moa increments. We never dialed up our scopes that whole last event. We just used holdovers.
Thanks

There's no way anyone on this forum can state the average muzzle velocity for your rifle; but, having said that, from what is known, that's to say, you have some results which indicate your velocity, it would appear your velocity is somewhere between 2500 and 2570 fps.

I hope you do not need to use holdovers for your next event. Holdover's require extraordinary picture memory development for the best results. You may not have such skill, or if the scope is not at the proper magnification setting, range finding and holdovers will not be accurate. This may in fact be much of your problem right now unless your reticle is in the first plane and is magnifying the reticle with the target. Also, if you will be using holdovers, be sure you bring a calculator as the math will need to account to the fraction. These things individually or collectively could put you an MOA or two off your target. In addition, in some cases, a 20 degree temperature change can be worth 50 fps which is worth about one MOA.

If possible, just get out to the practice range and chronograph your load again, recording atmospheric conditions, then, using something like the JBM Ballistics Calculator, calculate the bullet path at 100 yards above line of sight for line of sight and bullet path to intersect at 860 yards or thereabouts. Next shoot a tall target at 100 yards, adjusting clicks the amount of MOA of movement believed necessary to place your group at the desired point above line of sight. That's it. You will know what you do not now know; and, you will be well poised to properly analyze your work in progress through call/strike corollary at your next match.
 
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Pfiddy

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I just wanted to post in this thread so I can come back and read it again a few times. A lot of info in here
 

sled_mack

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Do a box test before you go any further. Make sure it tracks properly and is level. I've had a scope that did not track the full value stated on the knob. It will have you struggling for a long time till you get it figured out. And, it makes your hold-over value different than your dial value. You can't trust anything until you know the scope is valid.
 

The Lawn Ranger

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Yes, foget the chrono, other than getting an initial idea of what kind of settings are required to get on target downrange. Case in point: The OP used a chrono, and then his his dope based on said chrono didn't work. What was it again the chrono did for him in this case?

I would have to agree with Turbo here. After developing a "few" loads for multiple calibers the chrono
has been collecting dust. Real velocities are determined shooting at different ranges. (300, 600, 1000).

This is where loads are tweaked. It usually takes 9-12 rounds on an estimated velocity to figure out what
the actual velocity is when shooting at known 300/600/1000 yard ranges.

I also find you also begin to understand vertical dispersement a lot better when shooting longer ranges.

I can get a really accurate load at 100 only to find 18" of vertical at 1000.

BTW. I make micro velocity adjustments in JBM at 600 on clay pigeons- this works very well for me.
 
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The Revenge

Private
Full Member
Minuteman
Feb 21, 2013
41
0
Range report after dope a scope day:
Awesome day at the range.
I went to the range with two sets of ballistics pulled printed out plus my ipad standing by with isnipe. One set for the chrono number 2620 and then 2520 which is what an average was of most on here thought the ballistics would look like. I had them side by side and decided to start out using 2620 number since that was the chrono number.
We got two initial shots and then three shots per each round, repeating it if necessary before moving to next distance.
At 100yd rifle dead on.
At two hundred I used 2.25moa from isnipe and was right on.
300yd same thing. 5.25moa
400yd same thing. 8.5moa
500yd 12.5moa which is where the problem was before. Not this time.
At 600yd things started to change. I used 16.79moa first and was low, I ended up at 17.5moa and on target. This number is between the ballistics I had for 2620 and 2520.
At 700yd same thing. Started with 21.79moa and ended up at 22.75moa to be on target.
By now the wind was a 8-10knt left cross wind and was really messing everyone up. BUT I was still landing roughly within a foot of the target before my scope adjustments.
At 800yd my first two shots were low and right of target using the 2620 ballistics. I dialed up some more and ended up still about 8 inches low of the target, and slightly right, then we called it a day. Then we all realized the last target was actually at 850yd. They maxed out the range with the last target and we all assumed the target was just being moved another 100yd to 800yd. By then the wind was playing hell with everyone even the very experienced bench shooters there.
The targets were 4" orange circle targets out to 600yd then they switched to 6" orange circles for the rest of the range.
It appears the ballistics for 2620 work fine out to 500yd then after that you need ballistics for between 2620 and 2520. I haven't had time to break the numbers down further.
It was a great day and fun. Now I'm qualified to go use their 850yd range on my own so I can practice. It was fun shooting at 700 and 850. Also seeing how accurate this stock savage is.
I'm still going to do the other scope tests you guys recommended. I'm also going to attend two more long range courses by the end of the year.
I know have still have a lot to learn, in the mean time thanks for all your tips.
 
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Sterling Shooter

Gunny Sergeant
Full Member
Minuteman
Jun 10, 2004
2,842
13
Louisville, Kentucky
Yes, foget the chrono, other than getting an initial idea of what kind of settings are required to get on target downrange. Case in point: The OP used a chrono, and then his his dope based on said chrono didn't work. What was it again the chrono did for him in this case?

I would have to agree with Turbo here. After developing a "few" loads for multiple calibers the chrono
has been collecting dust. Real velocities are determined shooting at different ranges. (300, 600, 1000).

This is where loads are tweaked. It usually takes 9-12 rounds on an estimated velocity to figure out what
the actual velocity is when shooting at known 300/600/1000 yard ranges.

I also find you also begin to understand vertical dispersement a lot better when shooting longer ranges.

I can get a really accurate load at 100 only to find 18" of vertical at 1000.

BTW. I make micro velocity adjustments in JBM at 600 on clay pigeons- this works very well for me.

Real velocities are not determined by shooting at different distances. Velocity is determined by internal ballistics. We need to know internal ballistics to understand it's effect on external ballistics, which is our primary interest for an understanding about where the barrel needs to be pointed. The factors of external ballistics (trajectory) are gravity, drag, humidity, temperature, and wind. Since the chronograph is a very accurate means of determining average muzzle velocity, it can be used to understand pin wheel X elevation for any weather condition. This knowledge and a hard hold promotes the realization of a shooter holding proper elevation at distance, which effectively makes the target bigger, reducing the consequence for a less than perfect wind favor. Of course, any shooter on any given day will begin shooting with what is perceived to be the correct no wind zero and he will finish with the corrected zero. The closer the beginning zero is to the corrected zero assures the work in progress will be a better result. This is why the chronograph is essential for any one interested in winning at the highest levels of NRA LR Competition. Perhaps, it's your ignorance of the chronograph which has thwarted your progress. One thing for sure, your vertical dispersion of almost two MOA at 1000 yards, which you could not observe at 100 yards, would have been easily revealed by the chronograph if the error was about SD and ES. But without such findings you are forced to speculate whether you have a problem rebuilding the position or have an ammunition problem. Speculation is what novice shooters do. Really great shooters begin with the recognition that the bullet path is a definitive and uniform arc. With the chronograph, discovering things like high ES and SD allows you to better predict the bullet path shot to shot and seek a means to reduce the shot to shot divergence with a better hand load.

With a name like m14er I would suspect you shoot your M14 in Service Rifle Division of NRA LR, am I right. What is your classification?
 
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Sterling Shooter

Gunny Sergeant
Full Member
Minuteman
Jun 10, 2004
2,842
13
Louisville, Kentucky
Revenge,

Going from one ballistic profile to another as a means to adjust the sight for distance is not a solution. You will not get the desired result. I'm convinced your scope is not set to the magnification which correlates to stated reticle sub tension. This sort of adjustment will effect range finding capability, as well as realization of correct hold over. Sub tension error of course has profound consequence when shooting at distant targets. Just borrow a chronograph to get average muzzle velocity, and then get your scope's magnification set to yield correct sub tension.
 
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