Lewis guns. That big round barrel is the water jacket.
Edit: After zooming in, I see what you're talking about. That does look like a big flare gun.
Scroll down, you'll see the same image from a different angle here.
www.canadiangunnutz.com/forum/showthread.php/2433750-Random-Gun-Related-Images
I've seen and used quite a few Lewis Guns in my time, but I've never seen one fitted with a "water jacket"
That tube you see around the barrel conceals several flutes. The shroud assists in moving "air" over the flutes while firing and cooling the barrel to keep it usable. It also keeps down the "mirage" effect from heat rising from the barrel, between the rear and front sights.
I like Lewis Guns. If they're properly maintained, they are very reliable, even with ho hum ammunition. They operate well under some very severe weather conditions as well.
They would still be quite suitable for many combat situations today, especially in mounted or defensive mode.
Not saying they would be better but certainly capable in trained hands. The drums can be a blessing or a nightmare, especially if they're worn. They certainly keep ammunition clean.
We came across several of them that were kept in excellent condition, along with several drum mags for each. They had been stored in a locked room for so long, the key for the padlocks was no longer available. Maybe 25 years from the maintenance tag dates.
Just a light coat of dust and the internals of the mags/guns looked like they had been put away the day before.
Whoever did the last maintenance, likely a Portuguese REME, it was a labor of respect and affection for a valued and fine fighting tool.
