I just bought a side by side 12 ga. hammer gun with 30" barrels.

The left side plate says, "Manhattan Arms Co. and the right, "The Interchangeable".

I can find no serial number on either the receiver, barrels or fore-stock. However, there is the number 007 stamped on all three plus the wood of the fore-stock. In addition, the number 12007 is etched between the barrels on the underside. There are various other numbers and symbols stamped under the barrels. One such stamping says, "Choke 18.0/18.0.

"Belgium - Best Rolled Steel" is engraved on the rib and Choke Bore is etched into the left hand barrel. There are what appear to be four "Proof" marks on the breach block of each barrel. The stock has a silver shield inlayed on the butt of the pistol grip and the gun came with a steel butt plate that looks to be original.

The barrels are in perfect condition and all parts lock up tight. But what does "Best Rolled Steel" mean?

Anyone know what I bought myself into?

There was a thread here about 2 mths ago about a Jannsen Freres made 'The Interchangeable' marked 'Belgium Laminated Steel' which was clearly Twist. Cold rolled strip is sheet steel which has been rolled to thickness at low temperature in a continuous cold rolling mill operation. The steel is formed into a tube then welded lengthwise, and tends to split along the weld-an extremely bad happening.
http://www.hoosiergunworks.com:80/catalog/cross_reference.html does not list a "Manhattan Arms"

This is from a previous thread:

"Manhattan Arms Co was a trade name used on hammer and hammerless side by side imported by Schoverling, Daly and Gales, and also, Von Lenggerke & Detmold, both of New York city. The guns were made in Belguim by Neumann Freres and Fabrique d'Armes Fs. Dumoulin & Co., and in Germany by J.P. Sauer. The 1887 Merwin Hulbert & Co. catalog featured the hammer gun $25.65 to $37.50 and the hammerless gun for $68.00 for a 12 gauge, and $72.00 for a 10 gauge. Choice of barrels were in twist, laminated or damascus."

If those are cold rolled barrels with a longitudinal weld, then I would refrain from firing all but the lights loads in the gun.

Pete

While it is true bbls have been made by rolling a flat bar & welding with a loingitudinal seam, it is equally true bbls have been formed by "Rolling" a short fat cylinder into a long thin one. This may well be the method used to make these bbls. With this method the bbls were I believe normally rolled while at a red heat, over a mandrel with outside rollers to give the shape, unlike the modern cold forming methods of hammer forged bbls. The strength of a bbl made by this process would be dependant primarily upon the alloy of steel used, most likely a very mild alloy.

Do the proof marks look like this? (from the gun in the previous thread)

The 1912 SD&G Catalogue shows the Manhattan Arms "Interchangeable" hammer doubles in 12- amd 16-gauge. The No. N1 with blued barrels was $10 the No. N2 with "Twist Finish" barrels was also $10 and the No. N3 with "Oxford Damascus Finish" barrels was $11.

This shotgun has blued barrels. The bore is shiny with absolutely no pits. Is it possible to shoot this gun with light loads; ie, 1100 fps?

I'd suggest finding out for sure what sort of steel is underneath the blueing.

Its "POSSIBLE" but not with my eyes and fingers!!!