The Berman Museum in Anniston Alabama has some excellent gun collections. Col. Berman (IIRC) was an OSS type during WWII and the entire museum is just his souveniers of travelling the planet. And his souveniers manage to fill a really large building.
The Berman had the best collection of WWII infantry guns I've ever seen, including some prototypes of weapons that I had never even heard of.
I spoke with the guy who was incharge of defusing all of Berman's bomb collection as well. Apparently he had also brought home a whole lot of live munitions, land mines, and such. The dude had an interesting job to say the least.
There are also lots of armor, swords, art and other cool stuff.
Speaking of the Browning museum in Ogden, my wife announced that she is taking me there for Father's day. Awesome. John Browning is my hero!