Nightforce Problem?

Jay: Kyle Brown said he has had lots of people ponting out the numbers weren't right so they were going to eliminate the number and just have hash marks! Don't know if they have changed as of yet. Now my way of fixing the parallax problem, would be to have a coarse and a fine adjustment! Frank let me know if the full turn works for you.

Joe Salt
 
Going over my notes I find when I had problems getting on @ 1K I was usually low and right. I posted a question about yaw with no responses. I know there are some sharp folks on this site that already know the following. It seems with the 107 SMK @ 3000 fps I can expect around 13" of drift with a dead on 100 yard zero. I tried to paste a chart below but it didn't work so I will leave just one bullet that has a similar BC. Later! Frank

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.[22][23]

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

Palma Sierra MatchKing 155 gr Gyroscopic drift = 12.75 in / 324 mm @ 1K
 
Frank, where was your flags? the wind can blow many different directions in 1K. What size was the group? a full value wind at 1K would be with 13" of drift would be2-3 MPH....... jim
 
I haven't read any where on this thread the real reason the parelex adjustment is there. Everyone seems to be worried about "focus" and the corasponding numbers. The absolute most important thing the paralex adjustmenty does IS TO ELIMINATE PARALEX!! It is not a focus knob, although when the paralex is dialed out, the scope focus should be at is best. I have one NF that is not exactly in focus when the paralex is dialed out. When I wiggle my head around untill the cross hair stops moving is not the place where the focus is best. I am not trying to score a trophy white tail, so I don't care if it is not dead nutz on. I have won a lot of wood with that scope!!

Just my .02,
Tod
 
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Frank, I think you need a lot more flags. I have no idea what the range you shoot looks like but tree lines breaks in the tree lines and valleys mean a lot. Flags every 200 yds would be what i would use. to start with and what Tod said is fact.......jim
 
Went out to try 1000 again today. First shot on the target again and almost centered. A very good thing. Fired my first group with my #1 bullet. (105 Hybrid) The first three went 2.875”. The 4th shot went 13” low. (WTF) The 5th went right back with the first three opening the group to 3.5”. What a bummer. Had by best 1000 yard group going. Can’t imagine what happen. The wind was steady as usual blowing from 7 to 1. I only have two flags so one was at the target and one 20 yards in from of the bench. I guess if I am going to continue at this range I better buy a couple more. I used some of the suggestions you guys posted and appreciate them very much. Keep them coming. I have not seen the need to weigh cases and bullets or measure base to ogive. I think I will pay a lot more attention to the details. I have inspected the case that caused the flyer. Can't see a problem. The case was the 10th firing. I have had a few primers that were a little easier to seat with my hand tool. I absolutely need to run this load over my cronograph. It is shooting a lot higher than my 107 SMKs. I thought both were running right at 3000. Any ideas on the flyer? Thanks again for all the help. Later! Frank

PS: My range is laid out on a very big stubble field. For you guys back east this is a field that wheat was harvested from. It only has 20' of elevation change over 1K. There are no hills within 500 yards. This time of years the wind direction is most always the same.
 
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Frank, A condition change you had a let up, If you don't have flags use ribbon or surveyor tape to see the wind changes at all the way. Learn to read the wind and get a spotting scope, they help with wind reading and get a book on it...... jim
 
Frank are you weighing your primers? That 7 to 1 O'clock wind is a killer. And how did the one turn on the scope from 600 yards work or didn't you try it!

Joe Salt
 
I do have a good spotting scope. I have another flag and surveyer's tape. Need another tripod. My target cam gear is using one.

I wasn't weighing primers. After this morning's shoot I decided to build some rounds for a chronograph session tomorrow. I weighed 30 CCI-450s on my RCBS digital. They all came in at 3.7. Do I need to weigh them on my 5-0-5? All the bullets for tomorrow are right on their advertised weight. All the brass is within one grain. Primers are snug in all the cases. We will see.

Joe, I didn't try the come up from 600 you suggested. My scope was set for the previous 1000 yard shoot.
 
Frank,

I attended the 3-day class that the folks at Williamsport host annually this past April. The biggest point that they make is that consistency in your loads will give you the best chance at success for long range shooting. The low flyer that you experienced on your 4th shot could have been a result of something, anything being different about that cartridge.

Some that they spoke of were:
*Primers....do you weigh?....consistent seating pressure/crush?
*Powder charge....how accurate is your scale?
*Bullet....do you weigh?....measure base to ogive?....measure bearing length?....trim meplat?.....point meplat?....measure diameters?
*Brass....weigh?.....anneal?.....case volume?....uniform primer pockets/flash holes?.....cleaning i.e. ultrasonic?.....lube inside of neck before seating?....chamfer case mouth?....sizing die made for chamber?....consistent neck thickness?....consistent bullet seating pressure?
*All components.....NEVER MIX LOTS!
*Load testing......ladder test at 1000 yards?

The above examples aren't even close to all of the items given and demonstrated to the students. Were the instructors able to quantify measurable accuracy for each and every of the methods taught? NO. But absolute consistency is what they harped on.

What does any of the above have to do with a "nightforce problem"? Nothing I guess, but it seemed to be the way the thread was going. Of course, a little puff o' wind or the slightest gaff in bench technique can give any number of reasons for a shot to go out at 1000 yards. Just the nature of the game!

Jerry

P.S. Joe Salt was one of the teachers at the school. He knows long range. Just don't ask me to correctly pronounce his last name!
 
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Jerry, I am doing a lot of that and plan to do a lot more. I started the Nightforce topic and got my answer. Since I cannot high jack my own thread and had everyone's attention I just kept it going. As you can see there aren't many new topics in the 600/1000 forum. Thanks for your list. I am going to save it and go to work tomorrow. I have been wondering about neck tension since I am up to ten loadings and jumping .020". I have not annealed yet. Later! Frank
 
Frank' the primers weighed 3.7 WHAT! Should be using a scale thats in hundredths not tenths, it should be 3.70-3.78 and so on. You will be surprised how far off some are. And like Jerry said nothing wrong with your Nightforce!

Joe Salt
 
Frank B said:
I have never lubed inside the neck. Tell me about that please. Later! Frank
Click to expand...

http://www.neconos.com/category/Reloading-Aids-16 Bottom of the page. Super Deluxe kit.

Done as the last operation before dumping the powder charge into the case. This MUST be done after ultrasonic cleaning as the inside of the necks get "too clean" and can give any number of issues. In my opinion, it is good practice to do at every loading regardless of your brass cleaning habits. I feel more consistent seating when this is done.

Follow the instructions that NECO gives with the kit. They're pretty good.

A little tip on procedure: You'll notice that the moly appears to apply in what looks like streaks inside the necks. Not to worry.....after lubing the necks and wiping the moly powder from the outside of all of the necks, take a soft plastic bore brush and give the inside of each neck 2 strokes with the brush. As soon as you take out the brush, give the case a light tap with the mouth down on a paper towel or a rag. Any moly that gets loose during brushing comes out on the towel. I kinda twist the brush while stroking as well.

I feel the brushing and twisting makes for a more consistent result with the moly. Keep this brush in a small zip lock bag and only use it for this task. The first couple reloading sessions that you use the brush, give it a dip in the moly before you start brushing to apply some on the brush.

By the way....be neat when working with the moly as it can be very messy!

Jerry
 
I appreciate all the help. I really do! In a couple weeks I will be 69. I have a wife with Alzheimer's that I take everywhere I go. So far she likes to go out shooting with me. I haul all my range gear in the back of my 4X4. Unfortunately I am never going to shoot in a match. My immediate goal is to consistently shoot under 9" and work my way down. Most of the things you guys mentioned are within my means. I don't see a several hundred dollar scale to weigh primers in my future. I also don't see an auto annealing machine in my future. I did do some annealing when I was making TCU cases. That being said, how about a list of the most important to keep me busy. Thanks. Frank
 
Frank, I don't think you need a annealing machine, all you need is the set up Hornady sells,it goes on a drill and wind flags can be made from old election signs. I turned 69 today and i enjoy making my own things ....jim
 
Jim, I have a couple flags I bought from Bruno's a few years ago. They are made out of sign board with a Daisy wheel on the front. I am making one now. Later! Frank
 
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