To FAC or not to?

[Jack]

FAC rifles are cheaper than air rifles by quite a bit, shotguns to, indeed £30 will get you a single barrel chinese low quality item.
I would NOT go fac though. I have a small arsenal of air weapons and collecting strung weapons at the moment and that will be all I need for hunting as a tool goes.
Fac have greater ranges and more punch but here's the down fall
1- noise...
Even silenced they give away your position and tactically are a nightmare, people drawn to the bang may attempt to take your weapon (they may have a better rifle and skill to take it from you) and if they aren't interested in the weapon they will certainly want your ammo or the animal you just blasted.
Ammo-
Ammo will become a rarity and a liability, as mentioned your ammo will be desirable by everyone else, if not for their own weapons then as currency to trade food for.
You can as has been mentioned pick up live rifles if TSHTF in a big way anyway.
A non fac rifle can be tuned easily to put out higher powers after laws are no longer a concern (don't do this in 'peace time' or risk a 5 year stretch).
Air rifles are completely silent with a silencer past 50 yards (with the exception of the pellet hitting the target) are accurate in the right hands and ammo is more available and legal to stock pile in infinite amounts to prep. After you use up your pellets ammo is still easily obtained by stripping lead from roofs or wherever you may find it (car exhausts/batteries etc) and casting in a pellet mold.
Learning how to use traps effectively would be the best option for food. Low risk, low profile.
Guns for defence are ok if you leave no survivors otherwise you end up with a mob in your general area trying to separate you from your weapon, causing more problems or a need to bug out again! As an ex soldier I would acquire a weapon and keep at the ready but hidden until society corrected itself or was needed to protect my family at last resort, so for me a tactical shotgun would be my no1 choice.
Flash bangs, cs spray or blocks and other non lethal alternatives would be most worth while to as a deterrent set up at strategic locations if this question was indeed leaning toward the self defence angle.