Value is too difficult to be accurate without seeing the gun. Condition which includes the amount of original finish and original configuration will determine value. Auto 5's with poly-chokes, compensators and recoil pads (other than Mag 12's) will reduce value. Near mint guns and original box will command an extra premium. Recommend taking it to a gun shop for appraisal.
1938, Belgium
You need the services of a gunsmith
Go to Browning.com and you can download a manual
NO! The 1187 barrel was for remington shotguns,the auto-5 shotgun is a browning shotgun.
Your serial number X57552 indicates that your Browning auto-5 shotgun in 16ga.was made for Browning in the year 1951.
87 years old.If you have a 12 gauge shotgun then it was made in 1906,if your shotgun is a 16 gauge,then it was made in the year 1919.
Your serial number indicates that you have a Browning standard auto-5 shotgun in 16 gauge that was made in the year 1961.
The serial number L52789 indicates that you have a Browning light weight model,auto-5 shotgun which was made in the year 1955.
See what they are selling for at Gunsamerica. http://www.gunsamerica.com/ That should give you a pretty good idea.
No serial number provided
It shouldn't say light twelve on the barrel, but on the receiver. Light twelve means that the gun is a light weight version of the standard Auto5 shotgun.
Try here: Numerich gunpartscorp.comJack First jackfirstgun.comBob's Gun Shop gun-parts.com