it is very difficult considering the barrel could have been replaced but usely there is some wear on the inside
no. if gunpowder residue is on your clothes than someone or you had to have fired or recently handeled the fired gun while in that clothing
No
Yes. Cordite is part of gunpowder so any recently fired gun will smell like cordite
Type of rifling/twist.
After it's been fired!
science, Bullet markings and check them with the rifling of the firearm. Barrel twist and or markings can help ID the gun fired from. Nothing can tell you for sure, It can just tell you it was fired from a barrel like that of a type or make.
the bullet case
No it is not humanly possible
Not too much is significant about the gun Okonkwo owns. As Okonkwo is not a good hunter, it has rarely been fired. When Ekwefi is mad at Okonkwo she remarks the gun 'has never been fired.' Unfortunately Okonkwo hears this, and flies into a rage, discharging the gun next to Ekwefi.
No, but, they are able to use forensics to tell if a weapon fired a projecitle if they have an example.
When a gun fires, the primer and burning gunpowder eject residue. That residue is chemically like very few things OTHER than gunshot residue (GSR) If your clothes test positive for GSR, it is a pretty safe bet you were very close to a gun that was fired. It may or may not tell whether YOU fired the gun.
For a single shot rifle fired once: slightly warm.For a machine gun after a long burst: very hot (can even get so hot as to glow!)