Its not so much what it will take as it is how long it will take it, as Ky Jon notes. There are experiences here with frame cracking with the smaller-framed Flues receivers - doesn't happen all the time, but it does happen. I'm hoping that some readers pipe in here on their experiences.
On the plus side, there are tons of lower pressure loads that should afford your 16 Flues the long life it deserves. Handloading is one way (The 16 Gauge Group). There are certain factory 16 gauge loads that should work great, as well. Don't worry. With the right loads and assuming your gun is in satisfactory condition right now, there can be good times ahead.
Addendum
Lefty - - I checked Baschieri and Pellogri's site. They list seven 16 gauge 1 1/16oz. loads at a MV of 1280 fps. That's pretty stout. I did not find pressures listed, nor did I do so for B&P when checking the 16 Gauge Group's data on factory shells. I'd contact B@P and get pressure info, then post same here for folks to consider.
