308Nut

Another danger of using corrected yardage instead of actual drop inches is that line of sight still applies for MIL, MOA and click values at the line of sight range Example: By using the rifleman method of a 600 yards shot and shooting for 300 yards (600 * 0.5 COSINE). If you look at your drop chart and find that your 300 yard drop is 1 Mil from your 100 yard zero, and hold for 1 mil at 600 yards even though your drop chart at 300 yards says 1 Mil, it compounds the problem because 1 mil at 300 yards = 10.8 inches where 1 mil at 600 yards = 21.6 inches. If there is a bullet drop value of 79" at 600 yards from a 100 yard zero on a 0 degree shot, and you take 1/2 of that which is 39.5" and IF this method worked, holding for 1 mil which is the 300 yard holdover, an 18" mistake will occur. This is because 1 Mil at 600 yards = 21.6". You would be shooting for 21.6" where the rifleman method told you 300 yards or 1/2 the drop inch value which would be 39.5". 39.5 rifleman method drop - 21.6 1 mil holdover = 17.9" error. In other words, using a yardage cut of 300 yards will lead you astray because your drop chart says 1 Mil for 300 yards where you need a 1.8 mil hold for the shot. This is all of course based on the riflemans method which you all know I dont agree with and is for illustration purposes. Forget yardage cuts and go with drop inches. When the new drop inch is determined you will convert inches to MOA or Mils or clicks.

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Coach, You're absolutly right. We TOTALLY hi-jacked this thread. My apologies. Lionhunter, I am sorry we turned your thread into an abomination. Maybe in the near future I will send an article to Amanda and see if she wants to post it about the practical application of compensating for up and downhill shooting WITHOUT the vacume. rclouse79: Happy hunting. If I were to offer any advice, please dont take any shots up or down hill.

Just in case we are just misunderstanding eachother, the picture below illustrates what I am getting at. This illustrates a trajectory in a vacume. The summit is 1/2 way between the start and the end and the angle of departure is the same as the angle of arrival.

Assuming that we are talking about he same thing.......The fact still remains that a bullets trajectory in a vacume is still a parabolic. In a vacume, the vertical velocity (due to gravity) would decrease from the original velocity to zero on the ascending branch of the trajectory and increase from zero to the original velocity on the descending branch. Zero vertical velocity occurs at the highest point in the trajectory. Fact: The summit or peak of a trajectory in a vacume is half way between the begining and the end. Fact: The angle of the fall in a vacume is equal to the angle of elevation. x = vt cos θ y = vt sin θ - ½ g t² v is the velocity θ is the angle you launch it at g is the downwards accelaration caused by gravity = 9.81 m/s² t is time in seconds

I may once again have to beg to differ. Saying the bullet angle does not change (“arrive at the target at the same angle”) is another way of saying the bullet travels in a straight line path which is not true. Below I set up a theoretical situation to illustrate that. Lets say you shoot at a paper target 100 yds away on flat ground at the same height as the barrel and hit the bullseye. Lets just say the initial angle of the bullet was 1 degree above the horizontal. The angle of the bullet would be 1 degree below the horizontal when it hits the target at 100 yds (not the same). Now imagine the first target was on the beginning of a hill that perfectly matched the trajectory of the bullet. A target is placed every 100 yds from 100 yds to infinity. The same bullet continues to punch a hole through the center of each target every 100 yds. Imagine that the hill perfectly matching the bullets path is infinitely long. Eventually the horizontal component of the bullets velocity would be next to zero because it has been decelerating due to air resistance. By this time the bullet would have reached its terminal velocity in the vertical direction (the weight of the bullet is equal and opposite to the air resistance resulting in zero net force and zero acceleration in the vertical direction. a.k.a. maximum speed.) At this point the bullet would be traveling close to 90 degrees below the horizontal still punching a hole through every target every 100 yds. The angle of the bullets travel is not equal to its initial angle, but it still hits the target every 100 yds. Along the way the bullet hit every single angle from 1 degree above the horizontal to just about 90 degrees below the horizontal. In the post I was refering to you said 'Since there is no air resistance' (highlighted in bold) and now you shoot me down by using an example involving air resistance by saying 'due to air resistance' (highlighted in bold). So.....Which is it? The theory that I posed was based on your earlier previous post where you used a theoretical senario using NO air resistance. Without that, the trajectory would be a pure parabolic. In your last post you use air resistance. That said, in a vacume, on level ground the end of the trajectory will be at the same angle as the begining only in reverse. In our enviornment (air resistance), the angle wil be much different. In THAT context, you are right.

In theory, this would be negated by the fact that the trajectory is parabolic and would arrive at the target at the same angle it left the rifle. Or 180 degrees depending on how you choose to look at it.

Who is Chuck Norris?

rclouse79, You dont have to exit. You pointed out a very valid flaw in my explanation. Yes I understand the physics behind it, no I did not explain it properly. It was late and I was tired, my 21 month old daughter was tugging on me etc...... You're absolutly right about the straight line in a vacume with no gravity. There would be no need for correction regardless of any angles as there is no trajectory. Homestly I have no idea what I was thinking when I said it. What was said was said and it doesnt add up so to speak. I can live with that. So allow me to correct myself. In a vacume, (with gravity) the trajectories regardless of caliber, velocity, BC, etc...will all have the exact same center. Meaning that even though the maximum height of each trajectory is different, the highest point in each trajectory is exactally 1/2 way between the bullet's starting point and the ending point. In other words, the trajectories are purely parabolic. With this fact, in a vacume, the math involved is as simple as multiplying the cosine of the angle by the line of sight distance. With air density, the maximum height of the typical bullet trajectory is between the 1/2 way mark and the target AND will be different for each trajectory. In other words, the trajectories are not purely parabolic. It is because of air density that it becomes more complicated than just multiplying the cosine value by the line of sight distance. That is really the message and principal that I was trying to get accross. Thank you for pointing that out. For the record, you are 100% correct. Now somthing else to chew.................... Lets say we were in a vacume (with gravity). The shot is 950 yards with a 40 degree slope. If you take 950 and multiply it by .766 for a corrected yardage of 728 yards, making the shot as simple as finding and using your 728 yard Mil or MOA hold over?

Do you have an idea of what the angle was? Altitude? Temp? It looks like for you to have shot over his back at 400 yards, the angle was most likely 35-40 degrees. Less degrees if you were aiming for 400 yards and he was actually closer to 380 yards. In any event, using the riflemans method at 350-400 yards between 30-40 degrees would have helped tremendously. There is NO shame in missing SO LONG as you learn from it. If you never repeat this mistake than it was worth it. M

Mike, I thought you knew about gravity, I can't believe I trusted you to set up my shot last December Yeah. I bet you will never make that mistake again!! In all fairness, I can step up to the plate and admit that I used a poor choice of words. If you want to nit pick and find fault with what I said that is your right. That said, if any of you want to get into a debate on the ins and outs of shooting up or down a slope in the real world, in a vacume with or with out gravity or whathaveyou.....I am game for it for as long as you can sit there and take it. M

Time for more popcorn! In all honesty allow a guy to use a poor choice of words. Some experts have said things like 'the vacume of outer space'. Maybe I was a bit out of line thinking members here would understand what I meant.

I knew I shouldnt have brought those caribou down there last year and released them. I really didnt think they would breed with the deer population.

You have'nt supplied enough information to get the right answer. Air density, muzzle velocity, BC etc.... all plays a huge part in calculating an accurate number that you would use for compensation. The illustration used by coach does and excellent job of showing you the principals of shooting at an angle. The danger of using the riflemans method is that (due to trajectories) when the range increases and the angle steepens, the numbers are'nt right. For example, using my 338 Edge in standard air density at 600 yards with a 30 degree angle the bullet drop is 39" as apposed to 53" shooting level. If I were to take the actual cosine value of .866 for 30 degrees and multiply it by 600 yards the answer is 519 yards. My bullet drop at 519 yards is about 32" which is 7" different than actual. Why is this? Because all of the variables were not included. If bullets were fired in a vacume, simply multiplying the distance by the cosine would work flawlessly. Then again, if we fired our rifles in a vacume, there would be no trajectory, only a straight line. When you add the trajectory factor into the equasion, each indavidual trajectory has to be compensated differently for. The deeper the trajectory the worse it is as well. For example, using my 308 in standard air density, the same scenario as above yields 61" level and 46" angled. Looking to 519 yards shows me 36". This is now an even larger error than the flatter shooting Edge. The riflemans method will get you closer than nothing at all but to do it right you will have to employ a ballistic calculator for an accurate compensation or perform a very long equasion by hand. The numbers you need to do the math by hand are unfortunately also generated by a ballistic calculator. It is also important to know that angles are angles. It doesnt matter if it is an uphill shot OR downhill shot the formulas and equasions are the same for both. If you deduct 12" for a downhill shot, you will also deduct 12" for an uphill shot for the same angle. I hope that helps. M

Between the lower weight and cost, I am much more interested than I was before. I will be owning one of these very soon. Between the cost and weight it seems like a great alternative to the bi-pod, albiet I still feel that bi-pods have their place such as in very open terrain in dall sheep country where a super LOW profile is the only way to get her done. Sitting up would meen suicide from a success standpoint in those cases with their superior eye sight. However for deer hunting, moose hunting, elk hunting, caribou hunting, bear hunting etc.....I can see how these claws could be valuable. Thanks for sharing. M

Time to break out the popcorn................

Kathi!! That is awesome! When I saw your post I thought of Mark's new 308 and thought I might see it and then I realized that men dont like to share their girlfriends with their wives! LOL! Sure enough, it wasnt in the picture. Congrats on your 1st coues buck. That is an awesome first buck. M

Better optics, better tri-pods, better laser rangefinders, longer range rifles (guys are finally starting to figure out how to take advantage of them), droughts have not been as bad in recent years, decent game managment, guys have more patience these days, 1 hunter typically has several non-hunters to spot for him these days, backpacking into wilderness areas have become more popular, trail camera popularity, salting etc.... All that said, the big bucks have always been there. Guys are starting to figure out how to find and kill them and having the patience to hold out for the big one. Tight nit internet based groups like this one draw them out for all to see. Just my .02 M

Congrats Amanda. That is an awesome buck. With all of these October pix floating around, I may just have to adopt the idea of burning bonus points for October CWT tags!

What else can you say but WOW! M

Purely awesome buck. M

Gotta love those Edges.

The 180 AB will do just fine. It will open reliably to 1800 FPS and a bit less depending on muscle density, bone interaction etc....... That said, it sounds like you have been developing a load, finally found one that is accurate and are worried about it's performance. DONT WORRY!!!! It will do just fine. Even on those little coues bucks. M

sorry 308...a little south of there, by at least 2000 miles SHHHHHHH!!!! Youre suppose to let them chase their tail. If its the cam I am thinking of, it is in New Mexico anyways!

GPS waypoint: N66 27.090' W151 23.841'