I only made up 100 or so of those light loads. My son does not particularly like shooting revolvers at this time, so I fired them myself to be shed of them. Never tried it again, I have no reason to. My standard load is similar to J.D.s except I use 2F powder, a card wad and MAV 44.
My gun is likely a fluke...it's one of the early ASMs.....quality is pretty good and has details nearly as good as an old Colt.
The headspace is fairly tight. Only twice has this revolver had rotation issues: (1) when my cartridge case resizing settings got fouled and turned out to be setting the shoulder waay back, and (2) when the firing pin bushing loosened and started unscrewing itself (yes, it has a hardened, threaded bushing). Applied loctite, turned it back in and away we go. This was not as easy to spot as it sounds. The bushing only moved a slight amount to cause this perplexing problem.
I have a pard in Illinois who uses a 15 grain load of 3F and filler (cardboard) in all his 44-40 loads. No problems with primers backing out for him either. He used those loads in his Uberti SAAs for years before swithing pistols to OTs / .44 Russian. BTW, 15 grains is roughly half of J.D.s load of 1.9cc.
Remember too, that filler material adds mass to the effective projectile weight...actually the mass of the BP charge has the same effect. Could increase pressure just enough to compensate.
IMO, The powder charge and bullet are two items I'd move down my checklist. Gun and case criteria move up. Other cartridge criteria including flash hole diameter / sizing, and gun criteria such as the FP busing would be bumped up higher.
Regards,
Slim