(Testimony of Robert A. Frazier)
Mr. Frazier.
of the scope tube circle which adjusts the crosshair ring laterally for windage adjustments.
The diagram at the left side of Commission's Exhibit 555 shows diagrammatically the blade spring mounted in the telescope tube which causes the ring to be pressed against the adjusting screws.
We found in this telescopic sight on this rifle that this ring was shifting in the telescope tube 80 that the gun could not be sighted-in merely by changing the screws. It was necessary to adjust it, and then fire several shots to stabilize the crosshair ring by causing this spring to press tightly against the screws, to the point that we decided it would not be feasible to completely sight the weapon inasfar as windage goes, and in addition found that the elevation screw could not be adjusted sufficiently to bring the point of impact on the targets down to the sighting point.
And, therefore, we left the rifle as soon as it became stabilized and fired all of our shots with the point of impact actually high and to the right.
Mr. Eisenberg.
As I understand it, the construction of the scope is such that after the elevation or windage screw has been moved, the scope does not--is not--automatically pushed up by the blade spring as it should be, until you have fired several shots?
Mr. Frazier.
Yes; that is true when the crosshairs are largely out of the center of the tube. And in this case it is necessary to move the crosshairs completely up into the upper portion of the tube, which causes this spring to bear in a position out of the ordinary, and for this windage screw to strike the side or the sloping surface of the ring rather than at 90 degrees, as it shows in Exhibit 555. With this screw being off center, both in windage and elevation, the spring is not strong enough to center the crosshair ring by itself, and it is necessary to jar it several times, which we did by firing, to bring it to bear tightly so as to maintain the same position then for the next shots.
Mr. Eisenberg.
And because of the difficulty you had stabilizing the crosshair, you did not wish to pursue it to a further refinement, is that correct?
Mr. Frazier.
We sighted the scope in relatively close, fired it, and decided rather than fire more ammunition through the weapon, we would use these targets which we had fired.
Mr. Eisenberg.
Now, once the crosshairs had been stabilized, did you find that they stayed, remained stabilized?
Mr. Frazier.
Yes; they did.
Mr. Eisenberg.
How long do you think the crosshairs would remain stabilized in Exhibit 139, assuming no violent jar?
Mr. Frazier.
They should remain stabilized continuously.
Mr. Eisenberg.
Do you know when the defect in this scope, which causes you not to be able to adjust the elevation crosshair in the manner it should be do you know when this defect was introduced into the scope?
Mr. Frazier.
No; I do not. However, on the back end of the scope tube there is a rather severe scrape which was on this weapon when we received it in the laboratory, in which some of the metal has been removed, and the scope tube could have been bent or damaged.
Mr. Eisenberg.
Did you first test the weapon for accuracy on November 27th?
Mr. Frazier.
Yes, sir.
Mr. Eisenberg.
Have you any way of determining whether the defect pre-existed November 27th?
Mr. Frazier.
When we fired on November 27th, the shots were landing high and slightly to the right. However, the scope was apparently fairly well stabilized at that time, because three shots would land in an area the size of a dime under rapid-fire conditions, which would not have occurred if the interior mechanism of the scope was shifting.
Mr. Eisenberg.
But you are unable to say whether--or are you able to say whether--the defect existed before November 27th? That is, precisely when it was, introduced?
Mr. Frazier.
As far as to be unable to adjust the scope, actually, I could not say when it had been introduced. I don't know actually what the cause is. It may be that the mount has been bent or the crosshair ring shifted.
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