Help Understanding Energy, Distance, and Angled Shots

[wind gypsy]

A lot of this is hard to picture without the "sciency" framing, but it is correct.

But, we all know data is one thing, and shooting it is another. I invite everyone to try to shoot at a steep angle up or down a mountain. Almost guarantee that the dope will never match what you actually hit. Extreme angles introduce lots of influence from the change in position. The changes in centers of gravity significantly effect the recoil and influences on the rifle from the traditional flat shooting we do.

You mean to tell me that a guy with a Leupold CDS dial that is actually perfect for the atmospheric conditions and rifle/ammo on a scope that tracks correctly would still have a 0.4 mil (over 8") error on the OP scenario? gasp.

 

[hereinaz]

You mean to tell me that a guy with a Leupold CDS dial that is actually perfect for the atmospheric conditions and rifle/ammo on a scope that tracks correctly would still have a 0.4 mil (over 8") error on the OP scenario? gasp.

hahahaha, correct. Lead sleds at the range and CDS dials all day, every day. Don't worry, at extreme angles they will still get the hit when there is vertical wind deflection caused by compression of the wind as it passes over the mountain on the windy side when they are shooting up said mountain.

Me on the other hand, with all my fancy gadgets and new fangled learnin' means I can blame the cosine of the tangent cause I forgot to factor in the hypopatamus and the bullet didn't have enough cross sectionality because gravity and wind for terminal mushrooms.

It never comes down to learning how to shoot out in the field and proving the rifle system so you actually know what goes into the shot.

OP, you had a great question, and you'll keep adding knowledge and understanding to your base with questions like that.

 

[taskswap]

For those of us shooting at somewhat shorter ranges, let's say 300 yards, is there a general rule of thumb that can be applied e.g. "hold over 1MOA for up to a 45-degree up-angle, hold under 1MOA for up to a 45-degree down-angle"?

 

[hereinaz]

So to give some context on my question, I was shooting a 6.5cm with Barnes 127 grain lrx bullet. I had created my dope chart out to 400 yards at 0 degrees based on StrelockPro app.

I ranged a cow elk at 410 yards, angle corrected. With estimated angle at 30 degrees, it was a steep canyon. Shot was a perfect lung shot with the bullet lodged in the opposite shoulder blade, she didn't go more then ten yards. I wanted to know energy as I was concerned my shot was ethically questionable on a cow elk. 410 range corrected at 30 degrees is LOS of ~475 yards. Which puts me at 1950 FPS and 1073 ft-lb.

So are you saying it is better to use LOS with my range finder then input range into Strelock with angle to get MOA adjustment? Along with possibly estimating angle in the field not using my phone. Seems may be challenging in the field. Either way 400-500 is near my max comfort level for shooting game.

I think it is better practice to use the correct data in a calculator, and that is LOS and shot angle. Put the best information you have into it. Otherwise, you end up with crazy backwards calculations and weird workarounds that just complicate things, especially if you don't know what goes into the black box in the calculator.

Play with your ballistic calculator in your typical conditions to see what difference adding 5% makes. Then go out in the mountains and pick a rock, then guess the angle. See how close you are and what difference it makes.

You can also get a cosine indicator and know how to do the quick math if you have a dope card on your stock.

With the paper homework, you can take all the possible errors and add them up to see if you can keep the shot inside the kill zone at the distances you want.

If you are confident in the numbers, then take it out your rifle or your .223 trainer and practice in field conditions. Note what is happening and see if your method to call the shot works.

All of that is what snipers did in their DOPE (Data On Previous Engagement) to prove out their rifle in field conditions, before we got the "cheats" with our ballistic calculators. I thought I knew a lot and was hot stuff until I had my eyes opened when I got to train and talked with very, very smart professional shooters. I started taking my book learnin' out to the field and quickly got humbled when I realized my range performance meant very little with the many, many confounding factors with a cold bore shot in the field.

 

[hereinaz]

For those of us shooting at somewhat shorter ranges, let's say 300 yards, is there a general rule of thumb that can be applied e.g. "hold over 1MOA for up to a 45-degree up-angle, hold under 1MOA for up to a 45-degree down-angle"?

Yes, look up the rifleman's rule. Basically you always hold LOW (edited per BBob, thanks) at high angle shots.

Take your rifle and enter your ballistics into the calculator, and play with it. You can see how much difference it makes. The faster your muzzle velocity, the less it matters. That is why old school guys went with 25-06 and .270 for velocity to minimize error. And, that is why Weatherby really stepped on the gas for the guys paying big bucks for their hunts back in the day.

For a fast cartridge: elk, not gonna matter really. For mule deer, maybe. For coues deer, probably.

 

[Reburn]

If you want to read my explanation, it might help to associate it with all the bleeding on the drawing.

I probably should take this and develop it as an article in my weekly long range tips...

You missed the mark when you didnt put a hotdog sammich in there.

 

[SirChooCH]

If you want to read my explanation, it might help to associate it with all the bleeding on the drawing.

I probably should take this and develop it as an article in my weekly long range tips...

Where are these weekly articles for those who like to procrastinate work and read them?

 

[BBob]

For those of us shooting at somewhat shorter ranges, let's say 300 yards, is there a general rule of thumb that can be applied e.g. "hold over 1MOA for up to a 45-degree up-angle, hold under 1MOA for up to a 45-degree down-angle"?

Yes, look up the rifleman's rule. Basically you always hold high at high angle shots

What? Might rethink that answer.

 

[hereinaz]

What? Might rethink that answer.

Doh, hold low, the bullet will go high. Thanks BBbob.

 

[hereinaz]

You missed the mark when you didnt put a hotdog sammich in there.

I have to bait you to the conversation...

 

[hereinaz]

Where are these weekly articles for those who like to procrastinate work and read them?

Long Range Tip of the Week

rokslide.com

It is a sub-forum of the Long Range Hunting forum.

 

[hereinaz]

You missed the mark when you didnt put a hotdog sammich in there.

fixed it

 

[WCB]

For those of us shooting at somewhat shorter ranges, let's say 300 yards, is there a general rule of thumb that can be applied e.g. "hold over 1MOA for up to a 45-degree up-angle, hold under 1MOA for up to a 45-degree down-angle"?

A couple people have basically answered this but on steep angled shots assuming a 200 yd zero or the standard (1.5" high at 100) with a common caliber in basic guide talk I told my clients "aim for the heart" as most guys aim about 1/2 up in general. If really steep and close I told them to aim at the bottom of the heart or "just on bottom line hair". Worked like a charm for a simple in the moment instruction. And, if followed, resulted in a clean well placed shot. Had a couple guys not take the advice and shoot over a couple animals but luckily compensated on the follow up and done deal.

Had one client refuse to listen for 3 shots in a row at a dandy mule deer. about 300 yards out missed high all 3 shots. Asked where he aimed and he told my high shoulder first two and a little lower the 3rd. He of course thought "my gun must have been bumped. Had him shoot at a big rock and aim right at a spot...HIGH. Told him aim at a spot below it a little and basically center punched his original point of aim....walk back to the truck was quiet to say the least.

 

[Macintosh]

Non angle compensated—At 300 yards with my 270 shooting barnes 130s which slow down pretty fast, this is what my applied ballistics spits out:

At a 20 degree angle (which is about the average slope of many advanced-intermediate/single black diamond ski runs and feels pretty steep when youre on it) my AB says the elevation hold is .2mil different from a horizontal shot of the same distance, equivalent to 6cm or 2.5” at 300.

at a 30degree angle (which is quite steep for a overall slope angle, about like most “notorious” double black diamond ski runs. I think to be significantly steeper over a 300-yard long distance youre in cliff-bands or rocks of some sort in most terrain in the rockies Ive been in) my AB says there is a .3mil difference from same distance on horizontal. At 300 thats 9cm or about 3.5 inches.

At a 45-degree angle—that is steeper than your actual stairs and youd likely encounter only in exceptionally steep pockets of terrain on a slope or if more or less shooting off a cliff or a series of small cliffs— it’s a .6mil difference (1.1mil on horizontal, .5mil at 45 degrees), which is about 7”.

My takeaway is that at 300 and under its not a huge difference on a moderate slope and you probably could get away with not compensating for it at all—until it gets pretty dang steep or range increases, or both. My guess is at short ranges and moderate angles stacking it on top of other errors is more the issue and misses arent coming solely from this. Im also noting this is “canceling out” some of the built-in error of a mpbr zero at 300-350 yards once the trajectory goes below point of aim.
Obviously longer range and steeper angle is different. Also might look different with other cartridges.

 

[ResearchinStuff]

Op, to answer the other side of your question, that was too low of an impact velocity for your Barnes to really do much of anything. 1950 impact works great with an eld/tmk, but not very well with a mono.

 

[jake_eizy]

Op, to answer the other side of your question, that was too low of an impact velocity for your Barnes to really do much of anything. 1950 impact works great with an eld/tmk, but not very well with a mono.

Looking around I was under the impression 1800 fps is the lowest fps for good expansion on copper?

 

[ResearchinStuff]

i don't like monos below 3000 fps impact. Others are more tolerant of poor wound profiles and use them lower, but I don't think anyone has posted actual photos of devastation on game below 2000 fps impact. to be clear, dead animals are not the same as devastating wounds.

depending on whether you like to read or listen, check out the shoot 2 hunt podcast on bullets or the thread here on why match bullets for killing to learn much, much more.

Why Match/Target Bullets For Hunting

This is going to be a barrage of questions. It will help to view me as a skeptic relative to the matter at hand. I am going to do some load development for my new 6mm Creed. I live in the southeast where shots are rarely taken at more than 100 yards. But, I fancy that I will take a trip out...

rokslide.com

also, we have a whole thread devoted to killing stuff with the 6.5's, you can compare the wound photos there to what you remember from your elk kill:

6.5 Creedmoor/260 for Deer, Elk, and whatever else.....

Seeing that the 223 thread is such a success, I thought maybe I would start one for the Creedmoor/260. Seems like people are asking a lot about using them and various bullets, especially for elk. I've used mine for the last few years almost exclusively. I have some pics of bullet damage, albeit...

rokslide.com

 

[jake_eizy]

i don't like monos below 3000 fps impact. Others are more tolerant of poor wound profiles and use them lower, but I don't think anyone has posted actual photos of devastation on game below 2000 fps impact. to be clear, dead animals are not the same as devastating wounds.

depending on whether you like to read or listen, check out the shoot 2 hunt podcast on bullets or the thread here on why match bullets for killing to learn much, much more.

Why Match/Target Bullets For Hunting

This is going to be a barrage of questions. It will help to view me as a skeptic relative to the matter at hand. I am going to do some load development for my new 6mm Creed. I live in the southeast where shots are rarely taken at more than 100 yards. But, I fancy that I will take a trip out...

rokslide.com

also, we have a whole thread devoted to killing stuff with the 6.5's, you can compare the wound photos there to what you remember from your elk kill:

6.5 Creedmoor/260 for Deer, Elk, and whatever else.....

Seeing that the 223 thread is such a success, I thought maybe I would start one for the Creedmoor/260. Seems like people are asking a lot about using them and various bullets, especially for elk. I've used mine for the last few years almost exclusively. I have some pics of bullet damage, albeit...

rokslide.com

Thanks for this info. I will sift through all those posts and watch the podcast. I have started digging through the last link and it has good info.

I only have a picture of the lungs but the entrance wound was about the size of a ping pong ball. I am planning to switch to hammer bullets and/or build out a 300 WM for bigger game after all this. Thoughts on the 124 hammer hunter with a 6.5cm out to 500 yards on elk?

 

[ResearchinStuff]

just load a 130+ ELD or TMK and shoot them out to as far as you're proficient with the creed. the only reason to shoot monos is if you are required to.

for reference, a guy in the 223 kill thread just ended another moose with a 223.

 

[Macintosh]

@ResearchinStuff 3000fps impact velocity? Or 2000? Or did you mean muzzle velocity?

3000 fps impact velocity would shorten my effective range to mere inches, as that is already at or above muzzle velocity for many cartridges, so I guess I can lose this fancy scope?

Manufacturers will say 1800 (and even lower in a few cases) but be careful to define what you mean by “expansion”. 1800 is where you get a tiny mushroom at the tip, but the “expanded” part is still narrower than the bullet diameter. 2000+ is what I have heard most people say is minimum for expansion to about double caliber diameter, which I think is more what people mean when they think of “expansion”. Even barnes will tell you you need additional velocity above their stated minimum if you want 2x expansion. I recently emailed barnes to ask this question for their LRX .277 129 gr bullet, they replied 1400 was minimum to get 1.7x bullet diameter expansion and I should add a couple hundred fps if I wanted 2x. Barnes has a different velocity range for various similar bullets even within the same family (lrx) but even 1400 is significantly lower than I have heard before for lrx bullets. Its also past my ability to shoot so I doubt I have a need, but I have been figuring 2000min with ttsx. That gets me past 500 yards at any elevation where I can SEE 500 yards, so its plenty for me.


For what its worth, Ive had fine results on critters from antelope to elk with monos as low as 2500fps or so, just never needed to take a longer shot. Even the resident “killing bullets” guru cites 2200 fps as his minimum for “reliable expansion” with barnes monos, and his is the HIGHEST recommended impact velocity Ive ever seen.