I have been considering this for some time, but a lot of questions and some hard decisions still abound. I also have a 20g 311, but never see many and really don't want to alter it; but I realize it might be a better choice.
The 311 I am considering using evidently had the triggers/sears reworked by someone. Pull one trigger and both barrels fire. Pull the other instead first and only one fires. Couldn't see any wear, and no amount of jolting it UNLOADED will cause sear release. Anyone heard of , CAS use?,this? The gun appears as almost never used.
Wondering about backthrust and if the 12 could handle it better.
Also, idea of insert barrels has me wondering about using a surplus 7x57 barrel (7x57R better choice?) permanently silver soldered inside the 12 or 20. Might it be better to use a Savage barrel mounted to a vertical boss silver soldered in. Or would the (much more difficult?) cutting one barrel as a stub and installing rifle barrel in it work better. I know it would look better, but wonder about effect on remaining shotgun barrel, and on sighting picture when using as shotgun.
Guess I have a million questions and few answers.
Anyone done a build even remotely similar? ANY info will be greatly appreciated. I realize I could be headed down a stupid path til I have better info and clearer vision on this. Thanks, Pappa