New Tenex has damage...

Billy,
Give those boxes to Doug, Roger, and Ron. I would take them off your hands, but I won't be there today for you guys to beat up on.
See you next month.

Boyd
 
pacecil said:
Hey Tim, if you are going to grow up to be a big benchrest shooter you have to learn to pay attention to the little things, especially "little dents". Little dents in your barrel might cause you a problem; a little dent in the crown could be a real headache; a little dent any part is what we book-smart-a** engineers call a stress raiser and might lead to a problem for you. I'm sure you are already aware of what a little dent in your primers has caused! As for those little dents in bullets...well, just be careful!
Click to expand...

Well Cec I shot a bunch of 250's with them dents, How'd you do?....Cecil....Cecil...? I forgot,
I think Bill Meyers called it ... a keyboard shooter.
 
Well they shot fine..

Got 2nd place out of ten shooters. I didn't index them. I was shooting a factory Anschutz 54.18 MSR. We were shooting indoors (but drafty and cold) at 25 yards off of wobbly 3 leg tables. I shot a 250 12X and got beat by a full blown custom benchrest gun that shot 250 17X. Pretty enjoyable.
 
The Bullet's Flight . . .

I have a copy of Dr. Mann's book: "The Bullets Flight". My wife gave it to me as a Christmas present many years ago.

I recall that in one of Dr. Mann's experiments where he deformed the nose and the base of his lead bullets: He found that a deformed nose did not affect accuracy, but that a deformed base had a profound effect on accuracy.

Most of Dr. Mann's experiments were done with 38 caliber rifles and with lead bullets from a machine rest. Read his "stuff" and you realize the man was WAY ahead of his time, when it came to rifle ballistics.

Right Cecil?

Joe Haller (Mr. Frosty)
 
to Joe Haller...

You mention "many years ago" - I got "The Bullet's Flight when I was 16. Now, that was MANY years ago!

You also mentioned "machine rest". Actually what he use was a barreled receiver mounted in rings and then the whole assembly laid in a big V block. I wonder why nobody uses that nowdays in benchrest??

In the book Mann ran tests with a scope to determine if mirage had any effect on aiming. Basically he found it didn't. I've never been able to figure that out!
 
That might be because the scopes of the day were about 6 power including a simple lens system that would not pick up any but the most severe mirage.
 
tim said:
That might be because the scopes of the day were about 6 power including a simple lens system that would not pick up any but the most severe mirage.
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In which case you'd expect the effect to be MOST apparent, would you not?

Ben
 
Ben, just the opposite.The higher the magnification the more apparant the mirage.
Remember when Leupold first came with the 45x's folks first thought the mirage shooting would be tougher but you picked up stuff that the 36's did not.
This summer set up an experiment for yourself, set up your sporter with the 6x on a 50yd. target in the afternoon on a nice sunny day, then switch to the next gun with a 36x. I'd guess you'll detect quite a bump in "apparant" mirage. It's the same you just see it better.
 
Optically challenged

A friend had a 36X bumped to 45X and the mirage was intolerable. When Leupold hit the street with the 45X I assumed it would be similar but was pleasantly surprised. What is the difference - focal length???

I read somewhere that the mirage seen existed where the scope was focused and not a sum of the entire distance....
 
I guess that is my point. If the mirage is bad enough that you can see it in a 6x scope, there must really be some hopping air action downrange. If mirage is just an optic phenomenon that does not equate to point-stealing, bullet-moving air movement, it's just something to endure or ignore, n'est pas?

Ben
 
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Now you see it - Now you don't . . .

Dr. Mann did his mirage experiment in September of 1903. He was using a 16 power scope with a 1 inch objective lens. He was looking at 2 inch white circles at from 100 to 200 yards in three different directions. Claimed he could not see mirage. I would think if he had used white and black strips or looked at a horizontal line on the target frame, he could have seen mirage with that 16X scope.

Then too, he mentioned that at least on one day it was windy. Ya don't see mirage at a speed over 7 MPH.

And Wilber is right: You see the mirage at the distance the scope is focused. When I was shooting NRA smallbore prone tournaments: With irons I would focus my spotting score just a little short of the target. It worked. And with my 20X Lyman Super Target Spot I could see mirage: (When it was there.)

Mr. Frosty
 
ThaiBoxer said:
I guess that is my point. If the mirage is bad enough that you can see it in a 6x scope, there must really be some hopping air action downrange. If mirage is just an optic phenomenon that does not equate to point-stealing, bullet-moving air movement, it's just something to endure or ignore, n'est pas?

Ben
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It's an atmosphereic phenomenon. Just because you can't see it with lower power dose not mean it's not there.
Another interesting experiment with the 45's, set your gun up and aim at a 200 yard mothball on a nice sunny day a nd watch how the dot moves all over the place.
 
The question isn't whether or not you can see mirage with one scope or another, the question is whether mirage causes an error in aiming. Mann found that it did not. When I set up a scope on a bench looking through mirage I found that the crosshairs DO dance around on the target. In other words mirage did cause an error in aiming. I know other shooters have also found this to be the case. I also know that light rays coming from the target should be bent by the mirage and and this this should cause an error in aiming. I put all this in a post a long time ago but didn't get any real response at that time except that Mann must have just been wrong. Is that the opinion of everyone posting here?
 
The question to me is whether the mirage is a valid indication of moving air that will screw up my bullet's flight, i.e. Guerin's "wind that you can see". Since it seems that mirage is only visible at the focal plane the scope is set at, which is generally at the destination point, estimates of the displacement effect of the mirage should be pointless.

My experience seems to be to wait for the next breeze to blow out mirage. While I can just aim for the midpoint in a shimmering image, the bullet holes seem overly whimsical.
 
The mirage issue was on the board a couple of years ago. I hear shooters talking about the wind blowing a shot out when it really was the mirage causing them to aim in the wrong place. There are numerous articles on mirage and how to deal with it. I always shoot based on mirage first and wind second.
 
ProneShooter, I am with you on that 100 percent. My 45 power scope works just fine. I can see it when the guys with 36 say they don't see any.
 
Mirage

Proneshooter "I always shoot based on mirage first and wind second."

Could you please post your method of shooting for mirage first and wind second?

I for one missed the previous thread on this subject. Thanks.
 
ThaiBoxer said:
The question to me is whether the mirage is a valid indication of moving air that will screw up my bullet's flight, i.e. Guerin's "wind that you can see". Since it seems that mirage is only visible at the focal plane the scope is set at, which is generally at the destination point, estimates of the displacement effect of the mirage should be pointless.

My experience seems to be to wait for the next breeze to blow out mirage. While I can just aim for the midpoint in a shimmering image, the bullet holes seem overly whimsical.
Click to expand...

Ben in theory this works and frankly at the distances most rimfire is shot it becomes largely academic.
At longer distances in centerfire, for instance, you sometimes cannot even see the mothball at 200 yards and especially 300 yards. I only bring this to the table as an extreme example of the mirage question. When this happens you quickly learn what the mirage board is used for, again, virtually not needed at 50yards or so.
This is why the 45's, like Gordon said, often make shooting "subtle" mirage easier, the stuff you don't see at 36x but it might be worth a bullet hole or two.
 
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Wilbur said:
I read somewhere that the mirage seen existed where the scope was focused and not a sum of the entire distance....
Click to expand...

I think depth of field might come into it too. I was behind one of those big Unertl spotting scopes at 1200 yards a couple of years ago & you could see layers of mirage crossing over each other nearly back to your toenail.
 
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