I think any of us that have read Sherman Bells articles in DGJ
as well as some of the English articles feel very comfortable with "2 3/4" ammo in 2 1/2 chambers. I use STS cases and 22.5
gr. 7625 with 1 oz of shot and they are low pressure and fine. As stated many times there is only about 100 psi increase and of course the STS and WW are about 2 5/8 in length.