Is this a load of bull?


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K3
October 14, 2007, 05:08 PM
A guy at the range had a Contender in .338 Federal. Heckuva concussion even at an outdoor range, lemme tell you.

The guy said he was going to zero it at 100 yards. OK. He then said that the ballistics of the round were such that it would be zeroed again at 300 yards. I thought about asking him what the POI would be at 200...

Assuming the POI would be maybe 1-1/2 low at 200, muzzle velocity being 2700 fps per his claim, how could the bullet then rise again?

Now, I've taken a few physics classes, and I've got a nice compilation of ballistics references. IIRC, there are 2 points where the round crosses zero per se, but one is fairly close to the muzzle, say 25 yards give or take. After the 2nd point, the point where most folks 'zero' all the bullet does after that is drop due to gravity.

I have heard this rising bullet claim before. The guy said that for his .300Win zeroed at 200 yards, he could hold dead on at 1000 and hit. Now THAT is BS, as the POI is many FEET lower at 1000, depending on all the usual factors.

Was the guy at the range full of it? Or am I missing something here?

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rcmodel
October 14, 2007, 05:16 PM
To be on at 300, it would have be high at 100 and 200.

Assuming he didn't zero slightly high at 100 yards, you are correct.
What the guy said is a load of BS.

The guy said that for his .300Win zeroed at 200 yards, he could hold dead on at 1000 and hit.This could be true.
He may flinch so bad he lucks one in every now and then! :D

http://i81.photobucket.com/albums/j219/rcmodel/KTOG/1224.gif
rcmodel

K3
October 14, 2007, 05:21 PM
This could be true.
He may flinch so bad he lucks one in every now and then!

Ha!

Maybe he fired a .460 Wby Mag one time too many and developed a flinch that he can't shake!

Edit: Oh, and the .300Win guy was my wife's step dad. Drunk on bourbon. Ah the stories I hear.

Charles S
October 14, 2007, 05:25 PM
Is this a load of bull?

Yes....

BTW. I have a 308 Encore pistol barrel that is absolutely brutal....the very edge of what I can take personally in recoil.

I bet the 338 Federal in a handgun is no fun at all!

larry_minn
October 14, 2007, 05:40 PM
A guy at the range had a Contender in .338 Federal. Heckuva concussion even at an outdoor range, lemme tell you.

The guy said he was going to zero it at 100 yards. OK. He then said that the ballistics of the round were such that it would be zeroed again at 300 yards. I thought about asking him what the POI would be at 200...

I have no idea of that rd. OR they scope/distance from bore to scope. I suppose its almost possible. Say the bore is 5" below center of scope. So to hit dead on the bullet has to RAISE 5" due to distance. (in 100 yds) above/beyond what effect gravity has on it... So its possible the "arch" of the bullet would come back thru poa around 300 yds.
THink of it as firing a arrow. First target is 20' infront of you and second is 40 yards later. You mount a site a foot above arrow (guess you would need crossbow as dang hard to hold bow drawn that way) So arrow hits first target on raise and second on way down.

gravis86
October 14, 2007, 06:11 PM
Although he may have been full of it, there is nothing to say that is could not work. It is physically possible.

Let's say your barrel is perfectly parallel to your line sight. The trajectory would look something like this:
http://www.thehighroad.org/attachment.php?attachmentid=65497&stc=1&d=1192395618
(RED is Line of sight, and BLACK is trajectory)
But if your barrel was pointed slightly higher than your line of sight, the trajectory could be matched to meet zero at two different locations. Like this:
http://www.thehighroad.org/attachment.php?attachmentid=65498&stc=1&d=1192395618

Now, granted, it would not be the bullet that did the trick, it would be the gun and the angle of the barrel.

I'm not an expert on guns, perse, but I am very learned in physics. It is possible.

EDIT: Well, it took me so long to draw up those images, that Larry beat me to it.

cnorman18
October 14, 2007, 06:34 PM
I'm wondering if T/C makes a Contender barrel in .50 BMG--and if this guy will buy one...

If I'm going to shoot a .338 Federal, I want something that I have to hold with both hands--and that's hard to pick up.

My cannons all have to have wheels, too.

K3
October 14, 2007, 06:57 PM
The recoil was something to watch, that's for sure. He was firing 2 handed from a rest. It lifted up and back along an arc more than 2 feet. The concussion literally rattled my teeth. And LOUD, wow! I though Mosin carbines were eardrum busters. They may as well have suppressors.

larry_minn and gravis86:

I see what you're saying. The scope height was no more than 1-1/2 inches from the bore. Probably less because it was a small scope. Probably a fixed power, and I don't even think it had a 30mm front objective.

He was firing a 200 grain projectile at 2700fps and was a little high at 50 yards. Prolly an inch.

Despite all this, the thing sure did look like fun.

Werewolf
October 14, 2007, 07:23 PM
When I was in the Army (early '70s) we zeroed our M-16's at 25 yards. DI told us that at 200+ yards or so the bullet would be hitting at POA just like at 25 yards.

The DI's explanation was - see post #6...

I zero my AR-15 the same way to this day and get the same results. Around 200+ yards or so the bullet is back on POA.

I know jack about .338 but I'd still have to say that there is a very strong possibility that the guy claiming on at 100 and back on at 300 was not full of bull.

Harley Quinn
October 14, 2007, 08:21 PM
This is the reason folks can not hit what they are aiming at if this is where their mind is at. OP...
The correct information has been mentioned. The 338 with a heavy round is not going to be working like some of the flatter shooters either.

The theory was used for the 06 to have it 2" high at 100 right on at 200 and low at 300 by about 3" or so. Give or take a little bit. You math folks can figure it out. But what that did for an animal that was say twelve inchs thick at the lung area, it allowed you to be inside the kill zone in all those ranges if you had cross hairs on the middle of the animal. Same with a man at that distance and if you are holding at the diaphram you will hit high at 100 (chest) right on at 200 and into the belly at 300.

http://www.chuckhawks.com/rifle_trajectory_table.htm

This will spell it out better the table ^

Walter
October 14, 2007, 08:40 PM
Nice graph work. A picture is still worth a thousand words. :D

Walter

K3
October 14, 2007, 08:41 PM
This is the reason folks can not hit what they are aiming at if this is where their mind is at. OP...
The correct information has been mentioned. The 338 with a heavy round is not going to be working like some of the flatter shooters either.

Oh, I understand ballistics quite well. I usually zero for 200 with hunting rifles in the .30 caliber range, meaning I'm 1-1/2 to 2" high at 100 and in the neighborhood of 5 to 8 inches low at 300 depending on the load used and the cartridge. Most common hunting cartridges used in NA fall in this range if I'm not mistaken.

As I understand it, like Werewolf said, the first point at which your average bullet crosses zero is fairly close, like 25 yards. The 2nd point can be anywhere from 100 to 200ish, maybe more depending upon BC, velocity, bullet weight, altitude, and whether the shooter likes boxers or briefs. And this mans setup was what I considered normal. Normal scope height in relation to bore. Normal range muzzle velocity.That's why I found his described trajectory odd, considering that he was already high at 50. If high at 50, dead on at 100, then how on earth could he still be dead on at 300? The bullet has begun it's drop.

Oh, and I like the theory on the '06. Makes a lot of sense, especially in the terms you put it.

I usually chrono my rounds, get the bullet manufacturer's data, run it through several ballistics calculators to get a theoretical trajectory. Then I shoot. Where's the weak link in that? Well, it ain't Sierra or the chrono, that's fer sure.

The one that get's me is my drunk father in law's claim for 1000 yards. Seems when he's drinkin', he's made a lot of 700 -1000 yard shots. Hell, I can barely see that far.

Harley Quinn
October 14, 2007, 08:49 PM
We all seem to have a drunk around talking about the shots they made:rolleyes:

Most of those heavy drinkers, are just pathetic and we take it in stride and try and get along:)

Looks like you have a good handle on it :) have you ever tried to see a deer at that distance with or without help (glass) :p

The minute that bullet leaves the barrel if it is not angled up like 2" at 100 it is heading for the ground very fast. Drop a same weight bullet on the ground at the same time you are shooting one out straight and no angle up, they hit the ground at the same time if everything is flat. According to the math folks.

hksw
October 14, 2007, 09:38 PM
IMO, although I think the shooter is incredibly ignorant of his caliber and ballistics in general, it is possible to zero at 100yds and have it hit zero again at 300 yds. Was his scope about a couple feet above his rifle?

K3
October 14, 2007, 09:46 PM
Harley,

There is a big mule deer buck on our lease that I can see with no problem at 800 yards with the naked eye. 30" wide rack by all counts. He sure is something to watch. I spent hours last season admiring him. Never could get any closer due to the terrain, as I was sitting on the nearest rim and he was feeding in the flats. What a buck. Sometimes I swear he looks at me and thinks "I know you're there, and I know you can't touch me at this range, so :neener:" Maybe I'll don my tacticool gear, slither up on him, and put a .22lr round behind his ear. Yeah. That's what I'll do.

Normally, most deer at that range are identifiable only as generic deer with the naked eye for me. With 8X binocs, I can make 'em out pretty good, but they still aren't very big in the window. :D

CNYCacher
October 14, 2007, 10:03 PM
http://thehighroad.org/attachment.php?attachmentid=64727&stc=1&d=1191002538

K3
October 14, 2007, 10:05 PM
Nice rifle. :)

230RN
October 14, 2007, 11:22 PM
The one that get's me is my drunk father in law's claim for 1000 yards. Seems when he's drinkin', he's made a lot of 700 -1000 yard shots. Hell, I can barely see that far.

Yes you can. You can see for light years.

And tell that to the competition shooter who regularly punches Vs at 1000 yard targets.

With iron sights.

The angle of departure is about 50 minutes. On my Garand this was about 35 clicks on the rear sight, depending, with 168 gr Sierra BTHPs. Sight stood up like a periscope.

The bull is IIRC, thirty inches in diameter.

The V is ten inches in diameter.

I won't tell you how many Vs I've punched.

You'd call me a drunk.

Harley Quinn
October 15, 2007, 12:50 AM
Well I'll get into this.

The v as you call it is not an animal at 700 or 1000 yds.
If you figure the amount of energy left in a 06 at that distance it is pretty skimpy for a deer or a elk.

For paper it might be fine.

The shooter who has a target and knows his clicks for distance and windage is not the same as seeing a deer out at "what ever long distance" you are mentioning and dropping them with one through the heart, and then go find them, gut them, clean them, and haul them back to the truck.:uhoh: All while being three sheets to the wind:what:

http://findarticles.com/p/articles/mi_qa3738/is_200503/ai_n13638366

cracked butt
October 15, 2007, 01:05 AM
Its physically impossible to have the bullet cross the line of sight at 100 yards and again at 300 yards using any normal scope/sight setup. With a typical setup and a zero at 100 yards, the bullet crosses the line of sight somewhere between 25-30 yards out- the first crossing gets closer as the zero gets farther out.

Assuming the POI would be maybe 1-1/2 low at 200, muzzle velocity being 2700 fps per his claim, how could the bullet then rise again?

At that velocity, the bullet is going to loose another 3 minutes or so of elevation once it hits the 300 yard target.

230RN
October 15, 2007, 01:45 AM
Well I'll get into this.

The v as you call it is not an animal at 700 or 1000 yds.
If you figure the amount of energy left in a 06 at that distance it is pretty skimpy for a deer or a elk.

For paper it might be fine.

Oh, I agree completely, especially blending in as they do. I was just saying not to discount the possibility of long range shots. It wasn't clear what kind of target the "drunken father-in-law" was talking about --deer, black ink, or sheep. The context of this thread is more or less sorta-kinda hunting, but that's not necessarily what the DF-I-L was shooting at. And at 1000 yards, the remaining velocity of a .30-06 is still about 1300 f/s with about 550 ft-lb.

But definitely not a Sportsman's shot, although I think it was Jack O'Connor who reported several kills of sheep at around 700 yards --across canyons and gulches and the like. (With a .270.)

Maybe the DF-I-L just had short strides... like Col. Cotton Hill, or was weaving and lurching back and forth in his trek to the target --thereby increasing the apparent range when pacing it off. :)

I understand they changed the nomenclature a while ago, but there was a V printed in the middle of the bulls I shot at, and that's what they called them.

MinnMooney
October 15, 2007, 02:19 AM
Hey CNYCacher -

Looks like that rifle was drawn with Etch-A-Sketch !!

rcmodel
October 15, 2007, 08:46 PM
Its physically impossible to have the bullet cross the line of sight at 100 yards and again at 300 yards using any normal scope/sight setup.
++++1

http://i81.photobucket.com/albums/j219/rcmodel/KTOG/1224.gif
rcmodel

MachIVshooter
October 15, 2007, 10:33 PM
I'm not an expert on guns, perse, but I am very learned in physics. It is possible.

Perhaps with a .45 ACP pointed at a 65 degree angle and a sight mounted 400 feet above bore centerline.

I've got a lot of flat shooting rifles (.17 Rem, .220 Swift, 6mm Rem, .25-06 Rem, etc.), but none of them are sooooo flat that they can cross the line of sight for the first time that far out. Most any rifle zeroed at 300 will cross the first time inside of 50 yards. And the farther out you zero, the sooner the bullet will cross line of sight during ascent.

Harley Quinn
October 15, 2007, 11:03 PM
When I was in the Army (early '70s) we zeroed our M-16's at 25 yards. DI told us that at 200+ yards or so the bullet would be hitting at POA just like at 25 yards.

I have done the same thing with open sights, I have done it while mounting a scope also.
Put the rifle in a rest and (with bolt action) take the bolt out look down range and have a bulls eye there about 20' or so.

Have the bulls eye in the bore as you look through it, and sight in the scope on it dead center of the bull.

Go to the range and at 50 yds finish it up, you can be very sure this will be good and shoot some 3 shot groups or 2 shot and follow it up to the 200 or where you are happy with it. I like the 100 yd location to have it 2" high with most of what I am shooting.

With open sights, or peep I like the six oclock hold best.


Some more information.http://books.google.com/books?id=Rig6zMNlPQcC&pg=PA31&lpg=PA31&dq=six+oclock+hold+target&source=web&ots=keVuklPW2P&sig=UPh61xL5MhGoheDOpzRovJYVL7c#PPA32,M1

http://www.bullseyepistol.com/ron4.htm

CNYCacher
October 16, 2007, 12:52 AM
etch-a-sketch, etc

Ha! :) Got the point across though, right?

No that was free-hand with The Gimp.

I drew the targets with etch-a-sketch

Phil DeGraves
October 16, 2007, 01:37 PM
The bullet might still be on the rise at 100 yards, then be coming down again at 300. That is not unreasonable. That is why heavier bullets shoot high - recoil.

Charles S
October 16, 2007, 02:20 PM
A little knowledge is a dangerous thing. Again with a normal setup it is not possible. Sure put the scope a foot above the gun it might be.

Calculated Table
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yds) (in) (moa) (in) (moa) (ft/s) (none) (ft•lbs) (s) (in) (moa)
0 -1.5 *** 0.0 *** 2838.5 2.542 3219.8 0.000 0.0 ***
10 -1.1 -10.9 0.0 0.1 2813.0 2.520 3162.1 0.011 1.9 17.8
20 -0.8 -4.0 0.0 0.2 2787.6 2.497 3105.3 0.021 3.8 17.9
30 -0.6 -1.8 0.1 0.2 2762.4 2.474 3049.3 0.032 5.7 18.0
40 -0.3 -0.8 0.1 0.3 2737.3 2.452 2994.1 0.043 7.6 18.1
50 -0.2 -0.3 0.2 0.4 2712.3 2.429 2939.8 0.054 9.5 18.2
60 -0.0 -0.0 0.3 0.5 2687.5 2.407 2886.2 0.065 11.5 18.3
70 0.1 0.1 0.4 0.6 2662.8 2.385 2833.5 0.076 13.4 18.3
80 0.1 0.1 0.6 0.7 2638.3 2.363 2781.5 0.088 15.4 18.4
90 0.1 0.1 0.7 0.7 2613.9 2.341 2730.3 0.099 17.4 18.5
100 -0.0 -0.0 0.9 0.8 2589.6 2.319 2679.8 0.111 19.5 18.6
110 -0.1 -0.1 1.1 0.9 2565.5 2.298 2630.1 0.122 21.5 18.7
120 -0.3 -0.2 1.3 1.0 2541.4 2.276 2581.1 0.134 23.6 18.8
130 -0.5 -0.4 1.5 1.1 2517.6 2.255 2532.8 0.146 25.7 18.9
140 -0.8 -0.5 1.7 1.2 2493.8 2.234 2485.2 0.158 27.8 19.0
150 -1.1 -0.7 2.0 1.3 2470.2 2.212 2438.4 0.170 29.9 19.0
160 -1.5 -0.9 2.3 1.4 2446.7 2.191 2392.2 0.182 32.1 19.1
170 -2.0 -1.1 2.6 1.5 2423.3 2.171 2346.7 0.194 34.2 19.2
180 -2.5 -1.3 2.9 1.6 2400.1 2.150 2301.9 0.207 36.4 19.3
190 -3.1 -1.5 3.3 1.7 2377.0 2.129 2257.8 0.219 38.6 19.4
200 -3.7 -1.8 3.7 1.7 2354.0 2.108 2214.3 0.232 40.9 19.5
210 -4.4 -2.0 4.1 1.8 2331.1 2.088 2171.5 0.245 43.1 19.6
220 -5.2 -2.2 4.5 1.9 2308.3 2.068 2129.3 0.258 45.4 19.7
230 -6.0 -2.5 4.9 2.0 2285.7 2.047 2087.8 0.271 47.7 19.8
240 -6.9 -2.7 5.4 2.1 2263.2 2.027 2046.9 0.284 50.0 19.9
250 -7.8 -3.0 5.9 2.2 2240.8 2.007 2006.6 0.297 52.4 20.0
260 -8.9 -3.3 6.4 2.3 2218.6 1.987 1966.9 0.311 54.7 20.1
270 -10.0 -3.5 6.9 2.4 2196.4 1.967 1927.8 0.325 57.1 20.2
280 -11.1 -3.8 7.5 2.5 2174.4 1.948 1889.3 0.338 59.5 20.3
290 -12.4 -4.1 8.0 2.6 2152.5 1.928 1851.5 0.352 62.0 20.4
300 -13.7 -4.4 8.6 2.7 2130.7 1.908 1814.2 0.366 64.4 20.5
310 -15.1 -4.6 9.3 2.9 2109.0 1.889 1777.5 0.380 66.9 20.6
320 -16.6 -4.9 9.9 3.0 2087.5 1.870 1741.4 0.395 69.4 20.7
330 -18.1 -5.2 10.6 3.1 2066.1 1.851 1705.9 0.409 72.0 20.8
340 -19.8 -5.5 11.3 3.2 2044.9 1.832 1671.0 0.424 74.6 20.9
350 -21.5 -5.9 12.0 3.3 2023.7 1.813 1636.6 0.438 77.2 21.1

gravis86
October 18, 2007, 02:59 AM
A little knowledge is a dangerous thing. Again with a normal setup it is not possible. Sure put the scope a foot above the gun it might be.

Yet your chart has it zeroing at both 60 and 100 yards...

IOW, you just proved yourself wrong.:confused:

That is, of course, assuming I read that chart correctly.

Charles S
October 18, 2007, 05:15 AM
The guy said he was going to zero it at 100 yards. OK. He then said that the ballistics of the round were such that it would be zeroed again at 300 yards. I thought about asking him what the POI would be at 200...

Assuming the POI would be maybe 1-1/2 low at 200, muzzle velocity being 2700 fps per his claim, how could the bullet then rise again?

Yet your chart has it zeroing at both 60 and 100 yards...

IOW, you just proved yourself wrong

Interesting logic....????

Again, it is impossible for a Encore Handgun with any normal setup in 338 Federal to be zeroed in such a manner that the zero is 100 and 300 yards.

I honestly doubt you could set up any rifle in any hunting caliber that way, but I have never run the numbers.

Harley Quinn
October 18, 2007, 12:42 PM
I honestly doubt you could set up any rifle in any hunting caliber that way, but I have never run the numbers.

If everything is on a level playing field, you are correct it is not going to happen.

I guess if you were shooting off of a bench at 3' in height and your target was at 4' feet at 100' and the one at 300' was similar you might be able to adjust it so all will work out.:rolleyes:

Hills and valleys come into the situation when hunting if you are talking great distance it is a huge factor.

gravis86
October 18, 2007, 01:44 PM
Charles,

I misunderstood you. I thought you were trying to prove that zeroing twice was not possible. I get it now, you were proving that zeroing twice at 100 and 300 yards was not possible. My bad.

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