What is the mag fed rifle in the top right of that Dillinger collection pic?
As was said, it is a Winchester Model 1907 self-loading rifle. It fired a cartridge equvilent to a modern .357 magnum cartridge in ballistics, and had a 10 round detachable magazine. So it was basically a semiauto 10 shot .357 magnum rifle, which was a rather nasty gun to use in a gunfight.
It was designed by Thomas Johnson, who became Winchester's top gun designer after John Browning quit Winchester over his dispute with them over the Browning Auto-5 Johnson is better known for being the designer of the Winchester Model 12 and 21 shotguns, as well as the Model 54 Bolt Action Sporting Rifle, which was the predecessor of the Model 70.
The Mob that used the Browning BAR a lot was the Bonnie & Clyde gang. Here is a photo of Clyde with two Browning BAR's, and also a sawed off Browning Auto-5:
Sawed off Browning Auto-5 shotguns were pretty deadly close range weapons and popular among bank robbers back then. John Dillinger had a couple of them too.
There was a pretty good low budget horror movie last year called "Bonnie & Clyde Vs. Count Dracula"
Sadly, though, it completely flopped at the box office, and is not even out on video.
Here is the promo video for it:
http://www.youtube.com/watch?v=_R1RDHMGUCY&feature=player_embedded
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