I recently bought two of the Carl Gustav guns based on the M96 actions. Both are from the same Canadian dealer. I haven’t fired either but both appear to be in great shape although one MAY have a headspace issue. All of that said I am not complaining; I’m merely curious about whether others buying these old guns have had any issues not pointed out in the descriptions or discovered later? Just a nosy guy I guess.
I have had M96 headspace issues in a 6.5swede I had years ago. Cases were splitting at the neck and shoulder. Otherwise it shot beautifully. Eventually it went to the gunsmith, but for a year before that I just fireformed my brass with a very reduced load and gun show cheapo bullets (to stretch them a little before being loaded the first time), then after first firing a fully loaded round, they fit perfectly. I just did a light .002 shoulder bump and everything was fine.
These days, with the cost of bullets and brass, I’d never do this again. Cheaper to pay the smith to fix it up.
Also, don’t waste money on a gauge. Just measure SAAMI sized vs fired brass. The difference in size will tell you everything you need to know about your chamber dimensions.