(Testimony of Joseph D. Nicol)
Mr. Nicol.
Yes. Of course, we are dealing with two different types of ammunition. One is a lead projectile, and the other is a metal-case projectile. And the ability of the metal-case projectile to pick up and retain fine striations, even in spite of distortion and mutilation, far exceeds what the lead projectile will do.
Furthermore, the lead being a soft and low-melting-point material is more subject to erosion of hot gases. So that there are many more variables in the reproduction in terms of a lead projectile as over against a metal-case projectile.
Mr. Eisenberg.
You found enough similarities to satisfy yourself that there is an identification here?
Mr. Nicol.
I am satisfied that the two projectiles came from the same weapon.
Mr. Eisenberg.
Now, we have received testimony that the weapon which is marked Commission Exhibit 143 was rechambered but not rebarreled, so that a .38 Special bullet fired through the barrel would be slightly undersized.
Mr. Nicol.
Of course I have not had a chance to examine the weapon. But on the information that you gave me, this was originally manufactured for English ammunition, and has been rechambered for American domestic ammunition, is that correct?
Mr. Eisenberg.
Yes.
Mr. Nicol.
The undersized bullet going through an oversized barrel of course presents some serious identification problems, because it does not go through with the same conformity as a projectile going through the proper-sized barrel, so that it is apt to, you might say, skip and bear more on one surface than on another in subsequent firings, so that the identification is made more complex and it is expected that more dissimilarities occur under those circumstances.
However, at the points where it did reproduce at the land edges, as shown in this photograph, I found sufficient lines of identification to lead me to the conclusion that they had both been fired in the same weapon.
Mr. Eisenberg.
Is it consistent with the markings you found on this bullet that it had been fired in a slightly oversized barrel?
Mr. Nicol.
Slight. However, due to the malleability of lead, it does accommodate itself more than a metal-case projectile, and therefore, the evidence of being fired in an oversized barrel is not as pronounced as it would be if it were fired, let's say, a .32-20 fired in a .38 Special, which would be possible, and would give very distinct evidence of the difference in the size of the bullet and the barrel. However, in neither case is an identification completely precluded. What is necessary is that tests are available which have borne on the same surface. If this is true, and if the marks have not been mutilated, then an identification is still possible.
Mr. Eisenberg.
When you say the bullet will accommodate itself, you mean it will expand to fill out all or part of the lands and grooves?
Mr. Nicol.
Yes. Actually, with the pressure on the base and the inertia of the bullet, it is in a sense shorter and expanded in diameter to accommodate for the larger-sized barrel.
Mr. Eisenberg.
Now, I was not clear whether you drew any conclusion on the other three bullets-- that is, did you definitely--find yourself definitely unable to identify those bullets, or did you reach a "probable" conclusion?
Mr. Nicol.
I would say there was nothing, no major marks to preclude it. However, I was unable to find what would satisfy me to say that it positively came from that particular weapon. So that I would place it in the category of bullets which could have come from this particular weapon, but not to the exclusion of all others.
Mr. Eisenberg.
Is this short of the "probable" category in which you placed the Walker bullets, or is it in the same category?
Mr. Nicol.
This is in a gray area between black and white, and it is some what nebulous to pin it down to a precise percentage dimension.
Mr. Eisenberg.
Mr. Nicol, were you able to identify the type of bullet which is involved in each of these four exhibits--that is, the manufacturer of 603, 602, 604, and 605?
Mr. Nicol.
No; I did not attempt this, because I did not have an adequate reference collection against which to make the comparison.
Mr. Eisenberg.
I do not have any further questions, Mr. Chairman.
|
