doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Help with W.J. Jeffery & Co

Some time ago I bought a nice little W.J. Jeffery 12 ga at a auction.I knew the barrels had been honed but I found out today that it has 3 inch chambers, can someone tell me if this is factory or should the be 2 1/2 or 2 3/4. Is there barrel marks that will tell me?

Remove the barrels from the action and look at the barrel flats. The proofing marks which include the chamber length should be there.

It is possible that the chambers could have been lengthened in England, but doing so would require the gun to be proof tested again.

right barrel is marked 16 over 1 , a 12 over a c in a diamond and says nitro proof 1 1/4 shot.The left says the same except 14 over 1.There are British proof marks and the word "choke" .The only thing that is different is on the right barrel by the diamond is a sideways 4 and beside that is a number 8

1 1/4 is a fairly stiff proof and your gun should be quite heavy. Is the chamber itself that long, or does it just have a long forcing cone? You need a tight-fitting chamber gauge, or a dial bore gauge to tell where the chamber really ends and the forcing cone begins. If it just has long forcing cones, that's probably a later add but a good thing. If it has true 3" chambers, then someone has lengthened them from 2 3/4" and that's a bad thing. Have the wall measured at the end of the chamber...it needs to be 80 thou or more to be shootable. BTW the 16/1 and 14/1 are the original muzzle diameters, indicating a .669 and .701 muzzle, ie 60 thou (yikes) and 28 thou constrictions.

I have owned some English guns with original 3" chambers and 1 1/4oz proof. Usually they are marked with an LC in the diamond. But I've had 2 that were not so marked and were original according to the maker's records.

The gun's weight will be a very strong clue. If the gun weighs between 6# and 7#, it very likely started life as a 2 1/2" chamber. If it is 7# to 8#, it could have been a 2 3/4" chamber. Over 8#, either a 2 3/4" or 3" or longer. The 1 1/4 oz proof is usually associated with 2 3/4" chambers. I have seen WJJ guns in all three chamber lengths.

Remember, chamber length doesn't make it suitable for modern USA (SAAMI) spec ammo. It will need CIP spec loads or reloads of known lower pressure (I'd also suggest light shot loads and lower velocity). Chamber length is one of the least important factors in selecting a "diet" for your gun.

The gun weighs approx. 6 1/2 lbs , has 28 inch barrels and is small framed. The right barrel is .713 & the left is .684 ,there doesn't seem to be much of a forcing cone ,looks to be 1/8/ to 3/16 inch. Thats what I first noticed.My other British guns have longer ones.The proof marks are a crown over BP,a cross with a crown on top a "B" on the left a "C" on the right and a "P" on the bottom and a cross with a crown on top and a "V" on the bottom.

Based on the weight and the muzzle diameters you have provided, someone has lengthened the chambers and honed the bores. The yellow light in your head should be flashing. Get your wall thicknesses measured before you shoot the darn thing, and don't even think about using modern 3" shells in it.

Would this gun be safe with 20ga inserts?

49, Are the barrel dia. you have given measured at the muzzle or in the bore itself. The proof marks of 16/1 and 14/1 are very unusual for a 12 ga. gun, particularly the 16/1. I have never seen that tight a bore proof mark on a 12??? Those bore sizes if they are the bore, not at the muzzle,would be more appropriate on a 16 ga. not a 12. Something not quite computing there.Could it be a 16 that has been re-chambered and proofed to 12 ga.??