Most are made from Bismuth and antimony.
Muzzle loading bullets are still made from lead but even that is becoming a thing of the past.
The material from X-rays is 99% silver to start with but in order to get rid of the other junk is the reason that you refine it.
If you sold 5 pounds x 16 ounces = 80 ounces x $8.00 per ounce = $640.00.
Now convert this to TROY OUNCES.
If you were to sell this to a Refiner they will pay 90% of the Silver spot= $11.34 per troy ounce IS WHAT THEY WILL PAY YOU.
Chances are you did not get anywhere this amount.
It pays to do a Little research.
O.K. as far as bullets are concerned this was agreed on because the lead would cause LEAD POISON

IT IS O.K. TO SHOT SOMEONE BUT NOT GIVE THEM BLOOD POISON
Here is a little known secret.
OLD LEAD and I mean very old lead up to the early 1800's will sale by the ounce and will bring as much a SILVER.
For more information go to the SHIPWRECK TOPIC SECTION and scroll down to the Antique Lead section. You will be surprised at the value of old lead.
Peg leg