FAQ I
FtEj
FtEx
FtF
M4 ramps
Headspace
Dimpled Primers
Wear inside upper at cam pin clearance cut

FAQ II
Excessive windage
Excessive elevation
Damage to firing pin retaining pin
or
Bolt carrier "catching" or "hanging up"
Testing for a chrome plated bore

FAQ III
Combinations of barrels and buttstocks
Free float handguards
Damage to buffer/buffer retainer
Doubling/FCG
.223 vs. 5.56
Keyholing

FAQ IV
Cast vs Forged
Gas port sizes
Maker's marks
Big problems
kBs

FAQ V
Double feed
Short stroke w Staking a carrier key
FSB Removal w/ Front Sling Swivel Install/Removal
Vortex History and Questions
Flash Suppressors