If the Hornady brass is headstamped ".44 Magnum" and is only 1.225" long, then it is 0.050" shorter than normal .44 Magnum cases at 1.275". It probably comes from the new Hornady "Leverevolution" ammo that is loaded with their "Flex-Tip" bullets, which have a pointed tip and are longer than standard from the crimp groove to the nose.
While not as short as .44 Special brass (at 1.150"), this brass still could use some charge weight adjustment for near max loads.
For example, QuickLOAD thinks that a charge of 2400 under a .240 grain Hornady XTP bullet that gives the SAAMI max pressure in a regular .44 Magnum case will give an additional 5,000 psi in the shorter Hornady case.
This seems like a new and potentially dangerous wrinkle that Hornady has added to reloading the .44 Magnum. While 5,000 unexpected psi is not likely to break a gun by itself, it is added to (and compounds the effects of) the other multiple-thousand psi variations that can come from different powder lots, substituting primer brands, substituting bullets, etc. In some of the .44 Magnum guns that are not built like tanks, this might be the issue that pushes the situation to the point of a blow-up in the hands of an unwary handloader.
At least, it is a hard variation to not notice.