I’ve been following this one since it was announced. I might get a barrel eventually, but I’m not in a hurry.
It’s a bit watered down compared to the .440 Corbon, where the .429 lists a 240 gr. bullet at 1600 fps, and the .440 could reportedly push the same bullet to 1800 fps.
A poster on another forum ran some .429 over the chrono and it did come in just over the advertised 1600 fps. I have not seen reports of what the .440 actually does.
I think MRI is missing the boat a little with this one. People go to a big bottleneck cartridge to get more velocity. But MRI has reportedly discontinued the 10” barrels for the Desert Eagle. As it stands now, I can push a 240 gr. bullet to 1500 fps in the standard 6” .44 Mag. With a 10” barrel, I can get well over 1600 fps. with the .44 Mag. The .429 doesn’t seem to offer much more than what I can already do with the .44 Mag.
I’m interested to see if any of the component manufacturers develop any loads that (safely) take advantage of the increased case capacity over the .44 Mag.