Another Elsie Question
 

20 gauge 2 1/2 chamber feather weight. Opinions on lengthen the chamber. 2 5/8 or 2 3/4 or not do it. Or would thin walled Winchester Target shells be okay to shoot in it?

use any taperwall plastic 2-3/4 inch shell loaded to reasonable pressure factor you feel is safe for your gun,

I would not lengthen the chambers. Have you measured the walls at the chamber terminus? FW barrels are light and the walls should not, imho, be compromised. Fingers and hands are difficult to replace.

Just buy or reload the size and pressure the gun was built for—problem solved!

Being a sidelock gun, and a featherweight, what are the chances of the wrist cracking when using 2 3/4" shotgun shells. I would say that at least half of the L. C. Smith's I have seen have had the wrist cracked, or broken, at some point.

There are opinions, and there are facts
1. We have NO modern data as to the pressure rise of using long for chamber 20g shells. Bell's studies were 12g.
2. After some dumpster diving at the gun club, it was confirmed that modern 20g hulls are often shorter than 2 3/4"

https://photos.smugmug.com/Shotshell.../Shells1-L.jpg

3. Because the taper of the cones is sharper than the external taper of the barrel, forcing cones can be lengthened (metal removed) BY AN EXPERT resulting in a wall thickness no less than the end of the chamber, and by Boyle's law, pressure will be diminished. How much, no one knows

https://photos.smugmug.com/Barrel-Ev...eel%2011-L.jpg

4. I can testify that using AA 7/8 oz target loads in a c. 1924 Parker 20g with chambers close to 2 3/8" yields wicked recoil, presumable from the case mouth entering the cone

Opinion:
1. I would not lengthen the chambers of a small bore, or lightweight English 12 bore game gun
2. Consider forcing cone lengthening by a barrel specialist like Dean Harris
3. Find a load that runs shorter than 2 3/4" and is 7/8 oz at 1200 fps or less.

I have a special order 1927 LC Smith 20 GA Specialty Grade FW with two sets of
barrels and forends.

Also own two Long Range Smiths with both having signs of slight cracks at rear of tang.

The Specialty Grade 20 gauge gun has had the stock internals reinforced. No signs of any old or newer tang or stock head cracking.

More dumpster diving at Ben Avery yesterday
20g all 7/8 oz.
Federal Top Gun 2 5/8”; Federal Target 2 5/8”; Fiocchi Shooting Dynamics 2 5/8”; Challenger Target 2 11/16”