In his article on the Flattop 44 special Bisley, Ross Seyfried loaded and recommended loading them to a max of 30k psi. Ruger overbuilds everything, and I think these new model flattop's can probably handle a steady diet of the current 44mag SAAMI max of 36k psi. I feel like I have a pretty informed opinion on this, but would you really seriously entertain the opinion of some random guy on the internet? I definitely would not!!! Look, 25k, (which is about where Elmer took Colt SAA 44spls), will get you over 1200fps with a 250 grain cast SWC, which is about where most standard commercial 44 mag loads run these days anyway, so I don't see the point in loading much over 25k psi. Brian Pierce has published a lot of 25k psi 44 special loads in Handloader magazine over the last 20 years. Among those loads, one can do just about anything one needs to do with a 44 special or 44 mag. You can get a 280 grain LBT to almost 1200fps and a 305 LBT to almost 1100. Those two bullets at those velocities can pass all the way through Elk on broadside lungshots within 100 yards. If you need more punch than that, I suggest moving up to a bigger hammer. For me, that would be heavy 45 colt loads. BTW, all of those Brian Pierce 25k psi 44spl loads can be found at loaddata.com.