Help Understanding Energy, Distance, and Angled Shots

[Macintosh]

I shot monos for years. Still do but I favor bonded with high weight retention. Barnes does state 1800 fps minimum and LRX down to 1600 fps. Personally, I keep impact velocity > 2200 fps and never had any issues.

I did some testing with reloads. Not entirely perfect but best I could do. 1800-2000 fps minimal opening and not more than the diameter of the bullet. 2000-2200 fps some opened perfect others less than diameter of bullet. > 2200 fps all opened perfectly. Sample: Barnes 150 grain TTSX.

Nathan Foster (Terminal Ballistics), regarding monos, recommends > 2400 fps with monos. 2200-2400 fps he recommended high shoulder shots to quickly anchor game. Below 2200 fps he states delayed killing occurs.
Obviously with perfect shot though major vessels (Aorta, Vena Cava, Etc), will kill well below 2000 fps.

FWIW

I am curious to read the nathan foster stuff, is that something I can find with a google search? That also more or less mirrors what Form has said on the topic, i.e. LRX requires lower velocity than ttsx and other traditional monos, and somewhere between 2000-2400 is "safe" depending on how much room for error you want to maintain (I've heard all the above at times). I dont have the extensive experience, and I dont have any experience near low velocity threshold (all mine between 2400-2600 with ttsx were fine), so curious.

For what its worth this is the email exchange I JUST had directly with Barnes customer service:

Sent: Saturday, October 7, 2023 4:28 PM
To: Barnes Customer Service <[email protected]>
Subject: 129gr LRX .277 minimum impact velocity?

Hi,
What is your recommended minimum impact velocity to achieve greater than caliber diameter expansion in the .277 caliber 129gr LRX bullet?

From: @barnesbullets.com>
Sent: Tuesday, October 10, 2023 10:50 AM
Subject: FW: 129gr LRX .277 minimum impact velocity?

Thank you for choosing to shoot Barnes Bullets, all copper bullets. 1400 fps will get you about 1.7x expansion of the bullet's original diameter. If 2x expansion is desired then add approximately 100-200 fps.

Thank You
| Consumer Service
Barnes Bullets

Sent: Thursday, October 26, 2023 3:34 PM
To: @barnesbullets.com>
Subject: Re: 129gr LRX .277 minimum impact velocity?

Thank you. 1400 is far lower than I have ever heard before for a copper bullet, its even significantly lower than long-range specific lead bullets I'm aware of, so I'm surprised to hear that. Is there a caveat about bullet placement along with that, or can I expect 100% of my double-lung shots (ie no bone, etc) to expand to 2x caliber diameter at 1600fps?
Is there a chart or some publication you could send or point me toward with recommended velocities like this for various barnes bullets? It seems there are different velocities recommended for different specific bullets, even different weight bullets within one caliber/family.
Thanks very much,

From: @barnesbullets.com>
Sent: Thursday, October 26, 2023 5:48 PM
To:
Subject: RE: 129gr LRX .277 minimum impact velocity?

Hit the shoulder, a rib, between two ribs, angle in from the gut…..does not matter. All our LRX, TTSX and TSX bullet are designed to hit full expansion by the time they penetrate 1” to 1.5”…..MAX. Usually quicker. At which point they dump all their hydrostatic shock to the animal. Then, with the monolithic copper construction the bullet retains 100% wieight or nearly so, causing DEEP penetration. Best of both worlds! That 139 LRX is the lowest of our LRX expansion numbers. Typically 1500 to 1800, depending on which bullet. A couple, 22 cal 77 LRX and 25 cal 101 gr LRX are 1900 fps.
No. Sorry, no chart. Sort of a call/email me situation.
Thank You
| Consumer Service
Barnes Bullets

I am not keen to test this especially given the "marketing language" in the reply, but it makes it hard for a guy to know where to land in deciding where his own velocity cutoff will be. At minimum it seems clear it is different for various bullets even within same brand and "family".

 

[Formidilosus]

I am curious to read the nathan foster stuff, is that something I can find with a google search?

www.ballisticstudies.com

Some things he writes are correct, unfortunately mixed in is lots of nonsense that is sprinkled with the same “scientific” jargon to appear authoritative, but is easily refuted by legit medical studies and terminal ballistic testing.

For what its worth this is the email exchange I JUST had directly with Barnes customer service:



I am not keen to test this especially given the "marketing language" in the reply, but it makes it hard for a guy to know where to land in deciding where his own velocity cutoff will be. At minimum it seems clear it is different for various bullets even within same brand and "family".

1,400fps huh….

Maybe one day companies will realize their employees should be competent and knowledgeable.

 

[Mule3006Elk]

I am curious to read the nathan foster stuff, is that something I can find with a google search? That also more or less mirrors what Form has said on the topic, i.e. LRX requires lower velocity than ttsx and other traditional monos, and somewhere between 2000-2400 is "safe" depending on how much room for error you want to maintain (I've heard all the above at times). I dont have the extensive experience, and I dont have any experience near low velocity threshold (all mine between 2400-2600 with ttsx were fine), so curious.

For what its worth this is the email exchange I JUST had directly with Barnes customer service:



I am not keen to test this especially given the "marketing language" in the reply, but it makes it hard for a guy to know where to land in deciding where his own velocity cutoff will be. At minimum it seems clear it is different for various bullets even within same brand and "family".

1400 fps. Unless something changed IDK. I would not trust that one bit.

Old video but the low expansion is not impressive IMO

 

[Macintosh]

Agree, just throwing it out there to illustrate the difficulty in figuring out for ones self where the “line” ought to be, especially when it isnt consistent across their product line, and when the manufacturer is telling people something VERY different than others are. Its the kind of situation where I personally dont feel like I can trust anyone or anything on the topic that I havent seen with my own eyes. And even then, Id trust a dead critter more than what the bullet looked like.

 

[Mule3006Elk]

Agree, just throwing it out there to illustrate the difficulty in figuring out for ones self where the “line” ought to be, especially when it isnt consistent across their product line, and when the manufacturer is telling people something VERY different than others are. Its the kind of situation where I personally dont feel like I can trust anyone or anything on the topic that I havent seen with my own eyes. And even then, Id trust a dead critter more than what the bullet looked like.

100% agree. That is why I did my own testing. I want to make ethical/informed decisions regarding range.
My results mirrored what Nathan Foster recommended. 2400 fps + good to go. 2200-2400 fps high shoulder or hilar plexus. < 2200 fps no go. This is just my approach after going down the same rabbit hole years ago. They will kill < 2200 fps, for me, it introduces the expansion variable and I just didn't want any part of it.

If you want send me a PM. I have the projectiles from my testing and specific fps.

 

[Dobermann]

I am curious to read the nathan foster stuff, is that something I can find with a google search?

As @Formidilosus covered above, Nathan's stuff isn't great and has been covered on this forum before.

When I started getting into long range, a well-meaning person pointed me in the direction to read all of his books, and most of what mattered to me was just not accurate - but it took me a long time to find this out. Put my learning back significantly. Couldn't re-sell his books fast enough, and when I did, I felt guilty for passing them on to someone else.

For ballistics, look at the sources Form quotes here.

For the reliability, or not, of platforms, do some judicious reading on this forum.

 

[Macintosh]

.

For the reliability, or not, of platforms, do some judicious reading on this forum.

Could you clarify? Ive read on the topic on this forum, I believe I’ve read every single thread on the topic, and I dont think I said anything that contradicts that.

 

[Dobermann]

Could you clarify? Ive read on the topic on this forum, I believe I’ve read every single thread on the topic, and I dont think I said anything that contradicts that.

I was just meaning if you want guidance on particular rifles, his books are not necessarily your best source.

It's years since I read them, so don't quote me on it, but I remember him being underwhelmed by Tikkas, thinking Blaser were a bad design, and that rifles needed to be bedded.

You're better off going with advice from experienced people here.

 

[kevlar88]

@hereinaz (or anyone for that matter)
What's the correct solution:

A. Input 500 yards into ballistic solver and change angle to 30* = 6.75MOA
B. Use AMR of 433 yards and leave ballistic solver at 0* = 6.25MOA

All environmentals and ballistics were left exactly the same for both problems yet some how you end up with a different solution. I confirmed this with several different calculators.

 

[Harvey_NW]

View attachment 654275
@hereinaz (or anyone for that matter)
What's the correct solution:

A. Input 500 yards into ballistic solver and change angle to 30* = 6.75MOA
B. Use AMR of 433 yards and leave ballistic solver at 0* = 6.25MOA

All environmentals and ballistics were left exactly the same for both problems yet some how you end up with a different solution. I confirmed this with several different calculators.

I plugged it into my calculator and you are correct, it spits out 2 different corrections. The one thing I notice is when I plug in 500 @ -30° and click additional info, it says "click value at current distance, inch - 1.3, with Time of Flight .61 sec", and when I plug in 433 @ 0° it says "click value at current distance, inch - 1.1, with Time of Flight .52 sec". Interesting..

I can't answer why, but I have always left my rangefinder on corrected distance, and trued up my MV in the calculator based on that range. I use my chrono velocity and box BC to start, and within a few shots and a minor MV correction usually I'm fairly centered for vertical on 1 MOA plate at 400 and 800.

 

[hereinaz]

A is correct because it does all the calculations.

You can’t cheat the system. Don’t use compensated in the solvers. You will only create weird anomalies, especially when you go further than 400ish.

Time of flight matters because the bullet is affected by gravity that acts over time and horizontal travel.

Both bullet travels the same 433 feet in the horizontal plane that gravity acts.

But, the 500 yard shot takes longer because it actually travels another 67 yards in the vertical plane. That extra time means that gravity is acting longer. You see the time of flight difference. And that is why there is extra elevation to dial in.

 

[kevlar88]

A is correct because it does all the calculations.

You can’t cheat the system. Don’t use compensated in the solvers. You will only create weird anomalies, especially when you go further than 400ish.

Time of flight matters because the bullet is affected by gravity that acts over time and horizontal travel.

Both bullet travels the same 433 feet in the horizontal plane that gravity acts.

But, the 500 yard shot takes longer because it actually travels another 67 yards in the vertical plane. That extra time means that gravity is acting longer. You see the time of flight difference. And that is why there is extra elevation to dial in.

Perfect, thanks for the explanation.

 

[pyrotechnic]

This whole "gravity working over distance" needs to die.

Gravity effects the projectile during its time of flight. It always acts in a direction down to the center of the earth. This acceleration imparts velocity on that projectile which is entirely dependent on that time. This velocity, when combined with the time of flight, gives a distance the projectile travels towards the center of the earth.

Our line of sight may or may not be angled with respect to that. When our line of sight isn't perfectly perpendicular to the direction of gravity a component of that acceleration is now parallel to our line of sight and doesn’t appear to have any effect on the projectile's trajectory (from our POV).

Using the horizontal distance to target can give a rough value for your elevation correction, but falls apart at distance. It's been known as the rifleman rule. The improved rifleman's rule is simple applying the cosine of your firing angle to your dope, it supposedly does a bit better job, I haven't messed with it much to compare.

Imputting your firing angle into your calculator allows it to sum the acceleration vectors appropriately while it's doing it's numerical integration and get an actual solution.

At no point does projectile give a shit about the horizontal distance it traveled.