Get one of these gauges, in 308 Win, and size your cases to gauge minimum.
Never, ever, neck size, partial neck size, or try to size to the exact size of the chamber. You want to full length size, preferable with a small base die, and you want clearance between the shoulder and the chamber, and clearance between the case walls and the chamber walls. And use CCI #34 primers. If you use a "match" primer you are likely to have a slamfire. I have a number of FAL slamfire accounts I have copied. Luckily, they are all in battery, but, given enough tries, I don't see why one of them might not blow the bolt out the back in an out of battery slamfire. Don't blow this off. Use the least sensitive, which are the mil spec primers, in this mechanism. Match primers are intentionally less sensitive. Federal primers of all types are the most slamfiring primer around. Don't use them. Find the #34's and use them.
This mechanism had some sort of firing pin block, which fails enough that it is not hard to find a number of spectacular FN 49 out of battery slamfire threads on the web. This was a precursor to the FAL.
I don't know all the rifles you have, but if all you have is single shots and bolt guns, a FAL is a totally different animal. And a huge problem bolt gunners have with reloading for gas guns is they think the extracted case is chamber dimension. It is not! These mechanisms unlock while there still is pressure in the chamber. It is called the residual blowback effect. Pressure is below 750 psia, or whatever pressure level will rupture the case walls.
The desire is to pop the case loose of the chamber and use that pressure to keep the mechanism extracting while there is energy available.
This has the real affect of stretching cases, such as these cases fired in my M1a
And to make things worse, your FAL is a rear locking mechanism. This action really, really stretches cases. Not only at unlock, but before because the bolt to so flexible, the whole thing bows under compression. Front locking lugs bow, but they are only a half inch long, but when the lugs are in the back of the bolt, the whole bolt compresses, and the lugs, and you find for rounds fired in a FAL, they will stretch to a case head separation in short order. I recommend you fire your cases lubricated to reduce sidewall stretch. What happens with a lubricated cases, is that the case slides to the bolt head instead of being glued to the chamber walls and having to stretch in the mid section to reach the bolt face. Also, you can adjust the gas system down as there is less case friction. That makes extraction easier and increases the life of your extractor.
Take pretty much everything you learned about reloading for single actions, straight walled cartridges, and ignore it. A semi auto is entirely different.
My Mom and older sister fried corn tortillas in bacon grease, served them to the family, and nothing except similarly fried corn tortillas taste good to me. 
