Whether you do or not depends on where you live. As for countries not requiring a licence to buy .22 ammo, the United States is one.
No guns or ammo
Companies that make firearms, ammunition, and components of ammo.
Yes.
Stovepiping due to loose handling (limp wristing) of the firearm, use of poor quality ammo (particularly, poorly done reloads and use of cheap ammo in firearms which are picky about ammo), poor maintenance of the firearm, incorrect assembly of firearms built from components or parts kits.
Only in firearms chambered for it. SIG comes to mind, but, there are others.
Federal law states that it is illegal for a felon to posses firearms or ammunition.
No, Federal law prevents a convicted felon from possessing firearms or ammunition.
http://ag.ca.gov/firearms/forms/pdf/Cfl2007.pdf
Bob Milek was a renowned firearms writer and editor who contributed to several gun magazines such as "Guns & Ammo" and "Handguns." He wrote on topics related to firearms, shooting techniques, and gunsmithing. Milek was known for his expertise in the field of firearms and his precise and detailed writing style.
There are several different FFLs- Dealer, Pawnshop, Collector, various manufacturers and importers of firearms and ammo. Two most common- 01 Dealer and 03 collector of Curio & Relic firearms. Dealer- must intend to "engage in the business" of buying and selling guns. Before a FFL is issued, you must meet all other laws to run a business- business license, zoning, sales tax ID, etc. ATF gets fingerprint card, conducts background check- $200 fee. Collector- covers firearm 50 yrs old or older. Allow you to receive those firearms directly from sellers in other states. Not a license to "engage in the business"- it is to aid you in collecting. $30 for 3 years, simple application, no business license etc.
to my knowledge ammo unless mil spec only is iterchangable with any weapon that fires the same caliber
Depends on where you live. Laws vary state to state, country to country.