Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels and Ballistics


Reply

Ballistics beyond 2000 yds : do we need/trust them?

 
LinkBack Thread Tools Display Modes
  #1  
Old 01-28-2007, 10:54 PM
Silver Member
 
Join Date: Jun 2007
Location: Buenos Aires, ARGENTINA
Posts: 131
Ballistics beyond 2000 yds : do we need/trust them?

From the reading of so many posts about discrepancies in downrange figures from different programs ( commercial or free ) and being myself involved in the development of another package (now in beta) I asked myself : do we need to compute values beyond the 2000 yards mark?

While with my own knowledge and experience in LRH and ballistics fired a fast answer that doing so is futile due to innacuracies in the math models, especially at the transonic level, and not counting shooter's error at that distance and the almost ever present wind, my guess is that we cannot trust or need to push the envelope that far. Maybe for marketing reasons.

We have different drag models, differents algorithms, different books...(Pejsa, McCoy, just to name a few) etc, but so far I've never obtained from a certified source a true table showing real vs. predicted values. Not even in military circles, except ( and cannot confirm ) the ones involved in the CheyTac system.

Moreover, if we take that project into the scene, I've never found any proof of some claims ( and please do not take this statement as it not being possible or unreal )

In short, when some programs shows downrange values beyond 2000 yards, my best educated estimate is that they rarely are confirmed by real firings.

A couple of weeks ago I had the opportunity to check during a sniper exercise (Marines' Special Forces) under "somewhat" controlled conditions and up to 1200 yards the values I'm obtaining from my software.

Well, fortunately drop values were almost near the 99% of the threshold of accuracy ( field data vs predictions ) but when I tried to push the range out to 2000 yards, an experienced officer and a LRH himself, pointed out the many variables involved that otherwise can put in jeopardy a military operation, by not hitting the target with the first or two rounds. Beyond that they call in close air support [img]/ubbthreads/images/graemlins/smirk.gif[/img] [img]/ubbthreads/images/graemlins/smirk.gif[/img]

So, they don't need or foresee a future need for tables beyond that range. That prompted my original question posted here.

In short, I'll like to hear from more experienced shooters waht they think on this subject.

Thanks in advance!
__________________
regards, Gus

LoadBaseŠ Desktop & Mobile editions - the ballistics/reloading software solution
http://www.patagoniaballistics.com
Reply With Quote
  #2  
Old 01-29-2007, 12:47 AM
Official LRH Sponsor
 
Join Date: Jun 2004
Location: Fort Shaw, Montana
Posts: 6,796
Re: Ballistics beyond 2000 yds : do we need/trust them?

In my opinion, the main reason for the inconsistancies has more to do with the rounds being used at these ranges more then anything.

Take a 308 win.

Load a 168 to 178 gr match bullet to 2500-2600 fps and look where she drops below supersonic velocity anywhere from 1300 to 1500 yards depending on the elevation your at.

Some say that some bullets will remain consistant through the transsonic velocities. That may well be but every bullet to some degree will be effected in some way dropping out of supersonic velocity and seldom is there sustained level of predictable consistancy.

With the 300 Win Mag with a 220 gr smk at 2700-2800 fps and even with this added performance level you will be dropping out of supersonic velocity in the 1500-1700 yard mark.

The big 338 Lapua and 338 Edge will flirt with the 2K yardage in certain elevations with supersonic velocity but in many cases they will even be on the marginal velocity limits.

So to answer your question, do we need these predictions with most conventional rounds, probably not simply for the reason that most conventional rounds will not give you super sonic velocity to anywhere near this range and as such consistancy is such that it is nearly impossible to predict what that bullets ballistic personality will be as it drops through and below supersonic velocity.

Now take the really big 338 rounds based on the 408 CT case and in most environments you will get super sonic velocity out to the 2600 yard range. and in most areas over 2700 yards worth.

For these, yes they are useful but there probably are not enough of them out there in use yet to make it worthwhile.

I can tell you for a fact, in good shooting conditions, holding 1 moa out to 2500 yards is not a problem with this class of round. The problem is that if conditions are not ideal, you will play hell getting any kind of consistancy at these ranges.

Just my opinion.

Kirby Allen(50)
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
Reply With Quote
  #3  
Old 01-29-2007, 05:23 AM
PUBLISHER
 
Join Date: May 2001
Posts: 5,831
Re: Ballistics beyond 2000 yds : do we need/trust them?

Gustavo

Could you please add to this thread:

Where Are You From
__________________


Long Range Hunting Rifles

Long Range Rifles, LLC - Ready To Ship

Components and assembly by LRH Sponsors
Reply With Quote
  #4  
Old 01-29-2007, 07:14 AM
Platinum Member
 
Join Date: Jun 2001
Location: Potomac River
Posts: 5,057
Re: Ballistics beyond 2000 yds : do we need/trust them?

[ QUOTE ]
otherwise can put in jeopardy a military operation, by not hitting the target with the first or two rounds. Beyond that they call in close air support

[/ QUOTE ]

This man is an idiot and has never been in combat with snipers. I suggest if this is the type of people you are getting information from then your program will be just one more piece of computer code that breaks no new ground. I assume you posted the question to see if there is another side of the story.

I have to go and do something this morning and I will be back. When I get back I will back up what I said with proof if you wish.

In the meantime I would just say that this is the second time you have said you are a long range hunter and I would like to see some pictures of the Argentina country side and some animals. If you have no animals to show,at least let us see some country side.
__________________
The Smokin Fur Rifle Club
Reply With Quote
  #5  
Old 01-29-2007, 08:32 AM
Gold Member
 
Join Date: May 2001
Posts: 920
Re: Ballistics beyond 2000 yds : do we need/trust them?

Gustavo...

I agree with what Buffalobob and Fiftydriver said.

First, there is no "ONE" military framework that a mil-sniper shoots in.

Under some conditions, if a military sniper cannot make a first shot hit a 500yds, he will not take the shot... the target at that range might be availably only through a small window or port.

But under other conditions, snipers can harass enemies at very long range without being at risk - consider that snipers can keep the enemy from drinking water, from using the facilities, getting to the chow tent, just by raining accurate fire on the camp from 2000+yds, even if the hit ratio is <20%.

Being stuck in a fox hole for three or four days is VERY demoralizing.

In WW2, the Germans kept our guys dug in for days at a time, and it cost us dearly. We had NO snipers to shoot back, and iron sighted Garands were no match for the German K98 sniper rifles.

I think your marine friend didn't have much practical experience. Probably a yuppy who didn't get into college [img]/ubbthreads/images/graemlins/wink.gif[/img]

As to the civilian side of things... there is a fellow that was written up in Precision Shooting a few years back that shot a 308 (Ackley) at 3000 yds, and rang steel plates on a regular basis. He used a custom built scope mount with 7 degrees of tilt. He had NO problem with transonic velocities (transonic problems disappear with proper twist rates). He shot a prairie dog at that range - third shot.

There are folks that whack away at rock chucks at 2,500yds on a regular basis and hit well enough to eliminate "luck".

I shoot a a 50BMG with 145 moa of up available on the scope, so I think a program that works past 2000yds is just fine.

So I will vote FOR longer range ballistic software.

The biggest problem with the current "models" (G1 through G8) is that they are ALL based on artillery projectiles that are 2" to 4" in diameter... and then the data is "scaled down" for us. No one is interested in breaking ground and doing original ballistic work and developing models with a series of projectiles from .17" to .40" at the velocities that we use them.

So when you punch in the BC for the .224 69gr MatchKing, you are hoping that it will fly "sorta, kinda" like a 4" diameter G7 round... sorta kinda [img]/ubbthreads/images/graemlins/wink.gif[/img]

If you can get accurate predictions of flight to 3000 yds, then go to it. People WILL buy it.

It's absolutely amazing!! The better your rifle, the better your ammo, the better your flight predictions, and better your ranging capabilities, and the more you practice, the more "luckier" you get [img]/ubbthreads/images/graemlins/wink.gif[/img]

.
__________________
Here, kitty kitty kitty.

LRH member #23
Reply With Quote
  #6  
Old 01-29-2007, 11:03 AM
Platinum Member
 
Join Date: Jan 2003
Location: The rifle range, or archery range or behind the computer in Alaska
Posts: 3,514
Re: Ballistics beyond 2000 yds : do we need/trust them?

[ QUOTE ]
In short, when some programs shows downrange values beyond 2000 yards, my best educated estimate is that they rarely are confirmed by real firings.

[/ QUOTE ]


What good are my or your firing tests at beyond 2K going to do for anybody else? Unless they shoot the same caliber with the same bullets with the same twist with the same powder and the same primers at the same velocities, firing test only benefit the shooter doing the test.

As has been brought out MANY times here already, ballistic software will ONLY work for each user AFTER he has done his own tests with his own equipment. From there on, with an accurate BC and drag model for his own equipment, will he get accurate predictions for ever changing enviornmental conditions.

So to answer your original question. Without doing firing tests for each set of equipment, NO they cannot predict 2000 yard and beyond accuratly. My software cannot, yours cannot, exbal cannot, RSI cannot, sierra cannot. None. It is as simple as that. None ever will be either.

You must go do firing tests first for accurate predictions in other than your firing test conditions.
__________________
Long range shooting is a process that ends with a result. Once you start to focus on the result (where the shot goes, how big the group is, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.
Reply With Quote
  #7  
Old 01-29-2007, 11:30 AM
Gold Member
 
Join Date: May 2001
Posts: 920
Re: Ballistics beyond 2000 yds : do we need/trust them?

[ QUOTE ]
[ QUOTE ]
In short, when some programs shows downrange values beyond 2000 yards, my best educated estimate is that they rarely are confirmed by real firings.

[/ QUOTE ]


... Unless they shoot the same caliber with the same bullets with the same twist with the same powder and the same primers at the same velocities, firing test only benefit the shooter doing the test.

[/ QUOTE ]

So you say that if I'm shooting a 308 190gr SMK at 3000 fps, and I change powder and primer, and I'm still shooting a 190gr SMK at 3000 fps - my BC and ballistics change, and none of the previously data apply, all because I changed the primer and powder, but the velocity and bullet are the same???

... Hmmm that's first in ballistics.

That theory completely negates all the ballistic work done in the last 100+ years... and makes all the ballistic software useless, because there are no inputs for powder and primer.

Where did you get that "theory"?

Inquiring minds want to know [img]/ubbthreads/images/graemlins/frown.gif[/img]

I have been shooting and loading for over 50 years, and started doing velocity measurements and shooting long range in the early 60's... I have never heard of such a "theory".


.
__________________
Here, kitty kitty kitty.

LRH member #23
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: Ballistics beyond 2000 yds : do we need/trust them?
Thread Thread Starter Forum Replies Last Post
Trust Land roaddog1m Humor 207 12-09-2010 05:17 PM
Government Trust fariswm Rifles, Bullets, Barrels and Ballistics 0 09-26-2010 02:28 PM
What's new in Trust Land? specweldtom Humor 3 07-18-2010 04:04 PM
Would you trust this item.... JOSE A. MARINE General Discussion 4 08-25-2008 08:44 PM
how far would you trust this rifle mr.big Long Range Hunting & Shooting 26 04-07-2007 05:31 PM

Current Poll
Do you plan to buy a new custom rifle in the next 12 months?
YES - Of course - 72.72%
1,669 Vote
NO - wife/girlfriend won't let me. - 27.28%
626 Votes
Total Votes: 2,295
You may not vote on this poll.

All times are GMT -5. The time now is 03:25 PM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC