Choke and shotshell size

The choke restriction is usually indicated on the barrel either written or with *, we need a little more info as to what you have and what is indicated on the barrel. Chamber length is also usually stamped on the barrel either in inches or mm ie 70mm = 2 3/4" 75mm =3". what shotgun do you have?
 
everything should be stamped on the barrel, whether it is written in full or has a symbol to indicate. If there is absolutely nothing stamped indicating choke or chamber, you'll have to measure to determine what the specs are. Important to note, never assume that if a shell can be chambered, that its appropriate. For example, a 3" shell can be chambered in a 2.75" gun, so never assume that if that is the case, that the gun is actually chambered in 3". As mentioned earlier, it would help to know what gun you are referring to
 
It's an iver johnson "ideal" - that's all it says on the gun - the only word is on the whole gun is "ideal". I've simply inferred that it's its iver johnson because its single shot, and strongly resembles an iver johnson in a number of ways.
.

everything should be stamped on the barrel, whether it is written in full or has a symbol to indicate. If there is absolutely nothing stamped indicating choke or chamber, you'll have to measure to determine what the specs are. Important to note, never assume that if a shell can be chambered, that its appropriate. For example, a 3" shell can be chambered in a 2.75" gun, so never assume that if that is the case, that the gun is actually chambered in 3". As mentioned earlier, it would help to know what gun you are referring to
 
A pretty redneck way of checking chamber length would be to take a wooden dowel (a broom handle maybe) and tape the end for a snug fit in the chamber at the breech. Push the dowel into the chamber until resistance is felt. Mark the dowel at the end of the barrel and measure how far it went in. More than likely 2 3/4". For the choke measure inside diameter at the muzzle there are charts to give approx diameters of different chokes. (google is your friend) Again more than likely full choke, The best way is to have a gunsmith check it out.
 
good idea

A pretty redneck way of checking chamber length would be to take a wooden dowel (a broom handle maybe) and tape the end for a snug fit in the chamber at the breech. Push the dowel into the chamber until resistance is felt. Mark the dowel at the end of the barrel and measure how far it went in. More than likely 2 3/4". For the choke measure inside diameter at the muzzle there are charts to give approx diameters of different chokes. (google is your friend) Again more than likely full choke, The best way is to have a gunsmith check it out.
 
OK, when I do that it's 3 1/8" exactly - so I'm guessing that's for a 2 + 3/4 with room for the crimp to expand

WRONG! A 2 3/4" shotshell is 2 3/4" long once it has been fired. If you really do have a 3" chamber then it should handle 3" shells. Having said that, few old single shots were chambered for 3" and the chamber length should have been stamped somewhere on the barrel. You still haven't told us what gauge it is: only 12, 20 and 410's were ever chambered for 3" shotshells. If the chamber really is 3 1/8" long then I would suspect it has been lengthened from 2 3/4 at some point earlier in it's life as a factory job would be more accurately 3". I suggest having it checked out by a gunsmith who knows shotguns.
 
Take a dime can. if it wont pass the muzzle is full tight fit modified loose fit IC. Now watch lectures begin.
 
All it says on the barrel is "Ideal" - but I believe it's and Iver Jonson 'Ideal', 12 gauge shotgun - circa early 1910 - 20 ish

WRONG! A 2 3/4" shotshell is 2 3/4" long once it has been fired. If you really do have a 3" chamber then it should handle 3" shells. Having said that, few old single shots were chambered for 3" and the chamber length should have been stamped somewhere on the barrel. You still haven't told us what gauge it is: only 12, 20 and 410's were ever chambered for 3" shotshells. If the chamber really is 3 1/8" long then I would suspect it has been lengthened from 2 3/4 at some point earlier in it's life as a factory job would be more accurately 3". I suggest having it checked out by a gunsmith who knows shotguns.
 
I wouldn't shoot steel through an old barrel like that. Steel doesn't compress like lead and the strength of the older steel is not like modern steel. Without an accurate measurement of the barrel and muzzle to determine choke restriction, all we know is that the muzzle is larger than a dime.
 
Given the age of the gun, I would suspect it has a 2 5/8 chamber. Probably safe to shoot standard load 2 3/4 " plastic shells but no paper shells. The plastic shells are thin enough that the 1/8" extending into the forcing cone would not make a lot of difference in pressure. Paper shells are a lot thicker. I think your best bet would be to use it only for trap or skeet shooting and use a more modern gun with a chamber and choke intended for steel

cheers mooncoon
 
The old dime test is only valid if the bore diameter is very close to .728" and even then it is an approximation of the actual choke because you don't know the bore diameter. If the barrel steel is soft and there is more choke than you think then you stand a good chance of bulging or splitting your barrel to the rear of the choke. Then you will have at best a shorter sawed off barrel with no choke.
 
Just took it to the gunsmith and he confirmed the dime test results: Dime test indicated modified, gunsmith confirmed it's modified. He also strongly advised against running 3" ammo through it - that even though it may have been bored to take 3" shells, there's no way it was made for them, and the risks are just too high.
 
Back
Top Bottom