Dear Sir,
I have Possed a 12-Bore Gun Details: The Colindian(Regd)A Rifled Gun For Shot OR Ball. Non Fouling Smooth Oval Bore Rifiling MADE by Charles Lancaster Bullet of grains 750Max, cordite.Grade C. Kindly give the chambers size (2 1/2, or a super magnum 2 3/4) and how much cordite use, and if poosible to use number shots, SG, LG. and which type of ball used in the Gun? plese give the details.

SRPRAKASAM:
Firstly, congratulations if the gun is yours. The Colindian was Lancaster's version of the Paradox gun, popularised by Holland & Holland. An internet search on 'Paradox Gun' or 'Rifled Choke Gun' will give you plenty of useful information. Even though your gun was made very differently it was intended for the same purpose, and to safely shoot the same ammunition. The intention was to pattern well with bird-shot, and shoot a solid lead bullet as accurately as an express rifle, from the same barrels!

The Colindian should shoot a good cylinder-pattern with #6 lead bird-shot in felt-wad shotshells, ie perhaps 40 to 45% in a 30-inch circle at 40 yards. Other shot sizes, and plastic wads, will certainly alter the results but it is difficult to predict the outcome. You will certainly have to test it yourself with SG or LG, as that would probably not have been tested or published at the time. Cartridge length will almost certainly be 2 1/2 inches, but the length should be marked on the barrel flats. Later guns may have been made with 2 3/4" chambers, just measure them. If not clearly marked 'Super Magnum' somewhere on the barrels or flats, then it isn't.

The projectile best suited to the Colindian is almost certainly the 'Fosbery'-style projectile, which is slightly cotton-reel shaped, and typically weighs 750gr as a solid, or perhaps 690gr if hollow-nosed. The nitro versions of the cartridge would have been loaded with chopped cordite, moddite, axite etc, which are unavailable commercially in the west today. Best modern loads are published in the second edition of Graeme Wright's "Shooting the British Double Rifle", Chapter 14: Paradox Guns. I strongly recommend you purchase a copy.

I could post some sample loads, but have no idea what powders are at your disposal in India.

The info posted above is offered in good faith, but there are no hard and fast rules in dealing with vintage British guns. If you were to post a digital photo of the barrel markings and proof-marks on the barrel flats, we could be a little more certain of some of the above points.
Nevertheless, I hope this helps in some way.

Almost forgot: Photos of Fosbery-style projectiles from my mold.




Several custom mold-makers in Australia and US carry this pattern. This one is from CBE (Cast Bullet Engineering).

Marrakai, as remember Colindian is not H&H Paradox version, it's modified Lancaster twisted oval bore gun, been made as 16 and 12 gauge double guns only. 12G was 2&1/2" or 2&3/4" chamber versions. Been descriped as shot gun matched to IC choked smooth bore guns and as rifle - all buillets in 6" circle at 150 yards shooting 750 gr bullet over 30 gr of Cordite.

I have a hammer Colindian and made a mold for it very similar to a solid nose version of what Marrakai showed. In my case the bore is .018" out of round so I made the bullet the average diameter or .009" over minimum diameter and of course .009" under maximum. I have only shot the gun a little and am undecided as to whether I should have made the slug larger or not.
I load with 3 drams of 2F black powder (80 grains) then a cushion wad and finally a slug.
With 7 1/2 shot, the gun gives a pretty open pattern and I would consider it to be a 30 yard gun; good for skeet but certainly not something to take duck hunting.
It is a while since I measured the bore and forget the dimensions but also would not be surprised if these varied a bit over the years of production.

cheers Doug

Geno:
You are quite right, of course. I thought I made it clear that the Colindian was made very differently from a Paradox, but that the principle of shooting both 'shot and ball' was the same. If I gave the impression that a Colindian was a rifled-choke gun, apologies, that was not my intention.