SKB makes a 4 rifle, waterproof, airline approved travel case for guns. I have a 2 rifle case from them, and it is rugged as heck. Their cases come with a tow handle on one end, and casters on the other, which facilitates getting around airports and such. My 2 gun case easily holds a Remington 700 VSF in .308 with a 26" heavy barrel with a 4.5-14x50mm scope mounted, AND a Bushmaster Varminter AR in .223/5.56 with a 24" heavy barrel and a 3-12x50mm tactical scope mounted. I bought mine at Bass Pro for approximately $190, if I remember correctly.
Here is a link to some information at Cabela's website about these cases, and
here is a link at SKB's website about the 4 rifle case specifically. SKB also offers a $1,500 guarantee against damage to the contents of their cases during airline travel.
“Hard times create strong men. Strong men create good times. Good times create weak men. And, weak men create hard times.”
― G. Michael Hopf, "Those Who Remain"
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