
247 S.E.2d 624 (1978)
38 N.C. App. 152
STATE of North Carolina
v.
James Alton (Buck) GRADY.
No. 7814SC323.
Court of Appeals of North Carolina.
October 3, 1978.
*626 Atty. Gen. Rufus L. Edmisten by Asst. Atty. Gen. Richard L. Griffin, Raleigh, for the State.
Murdock & Jarvis by Jerry L. Jarvis, Durham, for defendant-appellant.
MORRIS, Judge.
The defendant has brought forward three assignments of error. He first contends that the manner of the investigation essentially constituted a suppression of evidence favorable to the defendant and resulted in a denial of due process.
The defendant's first argument is that he was denied due process when E. C. Ray was allowed to testify for the State at the first trial, contrary to true facts known to a detective and the district attorney, that he did not have a gun the night of the incident. The defendant argues that such conduct denied the defendant evidence that could have led to the corroboration of his self-defense theory by showing that the defendant was not shot with his own gun but with E. C. Ray's gun.
It is well established that deliberate deception of a court and jurors by the State's presentation of known false evidence violates the "rudimentary demands of justice". Mooney v. Holohan, 294 U.S. 103, 55 S.Ct. 340, 79 L.Ed. 791 (1935). Furthermore, a conviction secured by false evidence must fall where the State allows false testimony to go uncorrected. Giglio v. United States, 405 U.S. 150, 92 S.Ct. 763, 31 L.Ed.2d 104 (1972). Nevertheless, the false testimony, regardless of whether corrected, was at a former trial and did not prejudice the defendant since he was afforded a new *627 trial on other grounds. Furthermore, there was overwhelming, uncontradicted testimony that the decedent had no gun and that the defendant had been wounded in an exchange of fire occurring after E. C. Ray struggled with defendant and took away his gun. Finally, as pointed out below, the State cooperated by running all the tests on the bullet found in the defendant as requested by the defense.
The defendant also argues that the loss of State's Exhibit No. 7 (the bullet removed from the defendant's back) before the second trial denied the defendant a fair opportunity to present evidence in his favor. There is no question but that the State has the duty, within limits, fairly to disclose evidence favorable to the defendant upon motion. Weatherford v. Bursey, 429 U.S. 545, 97 S.Ct. 837, 51 L.Ed.2d 30 (1977). See G.S. 15A-903 and official commentary. The State clearly performed its duty in the present case. Indeed, at the request of defendant's counsel, the State arranged for the removal of the bullet from the defendant's back. Removal of the bullet was not necessary at the time for recovery from defendant's wound. The bullet was sent to the S.B.I. laboratories for identification of its caliber at the request of defendant's counsel. No further tests were requested by defense counsel and, because of the State's belief that the Ray weapon was not material to this case, the gun itself was not examined or tested. The ballistics expert, who had examined the bullet before it was lost, testified that (1) the identifying marks left on the bullet were compatible with marks left by the type gun belonging to the defendant, and (2) such marks were incompatible with those left by a Colt .38 caliber weapon. In view of the unequivocal and unimpeached testimony of the ballistics expert and the uncontradicted testimony that the decedent had no gun, the defendant has failed to show how the unavailability of the lost bullet denied him material evidence essential to his defense. There was no suppression of evidence by the State.
By his second assignment of error defendant contends that the trial court committed prejudicial error by allowing the ballistics expert to testify that the lost bullet could not have been fired from any Colt .38 caliber weapon. Defendant urges error in that not only was the lost bullet not identified as being a .38 caliber bullet but that also the ballistics expert was allowed to testify that the lost bullet could not have been fired from a Colt .38 caliber weapon which was never introduced into evidence. Defendant's argument has no support in the record or in the law.
A full reading of the testimony of the State's ballistics expert makes it abundantly clear that the lost bullet had been identified as a .38 caliber bullet and that it had been fired from a .38 caliber weapon with rifling of eight lands and grooves with a right twist. Secondly, defendant now argues that any testimony that the lost bullet could not have been fired from the Colt .38 should have been excluded since the weapon was neither examined by the expert nor produced at trial.
The caliber of the bullet examined by the expert was within his personal knowledge. The fact that E. C. Ray's gun was a Colt .38 is supported by the evidence and was properly included in a hypothetical question submitted to the witness. See 1 Stansbury, N.C. Evidence, § 136 (Brandis Revision 1973). In response to a hypothetical question, the witness expressed his opinion that State's Exhibit No. 7 (the lost bullet) was not fired by a Colt .38 caliber weapon. North Carolina has recognized the competency of ballistics experts to express opinions on the caliber and the source of bullets. State v. DeMai, 227 N.C. 657, 44 S.E.2d 218 (1947). The expert's testimony clearly demonstrated that he was familiar with the characteristics of Colt .38 caliber weapons. In response to a properly phrased hypothetical question, fairly supported by the evidence, the expert witness expressed an opinion based on knowledge well within his sphere of expertise. There was no error in allowing the opinion into evidence.
Finally, defendant asserts that the trial court erred in allowing Dr. Woodhall's testimony on the condition of the decedent's *628 arm at the time of the incident. The doctor's testimony was based on his treatment of the decedent in 1950 and his prognosis of the extent of permanent disability suffered by O'Neal as a result of the injury suffered in 1950. Dr. Woodhall, a stipulated expert in the field of neurosurgery, testified to the extent of the injuries from his own personal knowledge. The injuries included the complete loss of the nerves which control the grasping of the fingers, the pulling-in of the wrist, and elevating of the hand. There was also the loss of the main blood supply to the arm. Based upon his testimony on the permanent nature of the injury to O'Neal and considering the lay testimony on O'Neal's physical condition at the time of the incident, the medical expert's opinion on O'Neal's ability to open a car door or to strike someone with his right hand was competent. Cf. Jones v. Shaffer, 252 N.C. 368, 114 S.E.2d 105 (1960) (physician diagnosing permanent disability allowed to express opinion on patient's ability to perform certain work); see e. g. 1 Stansbury, N.C. Evidence, § 135 (Brandis Revision 1973), and 6 N.C. Index 3d, Evidence, § 44. The lapse of time from the treatment of O'Neal to the time of the incident goes to the weight to be accorded the expert's opinion, not its admissibility. See e. g. 2 Jones on Evidence, 6th Ed., Opinion Testimony, § 14.31 (1972).
The defendant has abandoned his two remaining assignments of error.
No error.
HEDRICK and WEBB, JJ., concur.
