You might get a little bit of carbon on the cases, but I've shot 4.5 grs. of Red Dot and found it to be an accurate and pleasant load for the .44 Spec. with any 200 gr. - 250 gr. cast bullet.
Seems like I remember that Elmer recommended 5.0 grs. Of B'Eye with a 250 gr. Keith in the .44 Spec.
I see no reason why 4.5 grs. of Red Dot would not work well.
Here is what Alliant has to say about B'Eye in the 44 Spec. Of course B'eye and Red Dot have similar ( but not identical ) burn rates .
Quickload shows 4.5 gr of Red Dot at 775 fps and well within SAAMI pressures. Upping it to 5 gr gives 825 fps and pressure is at max. Even at 5 gr it is lower pressure than 7.5 gr of Unique which is actually over pressure for 44 special. That said, the SAAMI spec for 44 special is pretty anemic, the 7.5 gr of Unique load is only 19 K PSI. A well made, modern revolver isn't gonna be harmed by that pressure level.
I will be staring at 4.5 gr of Red Dot and then see if I need to go up.
I remember owning ( 30 yrs. ago ) a Charter Arms Bulldog in 44 Spec.
I read about the 7.5 gr. of Unique load and made a single " Test Round " of that load under a 250 gr. Keith SWC.
WOW ! ! I thought the little Charter was coming apart. No more of that for me.
In a larger N Frame Smith or my Super Blackhawk the load would have been OK, but not in the little Charter.
I agree, the Charter needs to stick with lower level loads. I have only shot one of them and it was a handful even with factory loads.
The 624 handles 6.5 gr of Unique quite well for me so I am sure it will do well with 4.5 or Red Dot. Some day I will try some 7.5 gr of Unique loads. No need for heavier loads with 2400, I have a nice 44 mag for that.
Use Red Dot a lot in the. 44Spl and the 232gr SWC Gordon Boser designed. 4.3gr is a creampuff from a 4" 629, and 5gr is smooth but hits hard enough with great accuracy for me. And yes, a might on the sooty side, but we know how to clean anyway huh? And I get nearly the same result with the Keith bullet as well. I think along the same lines where if I want magnum loads I'll load a magnum case. That's a no brain-er.
It appears you have your answer. I haven't loaded much 44 spl.
But I can say, I do like Red Dot in 41Mag with 196gr WC. I use 6.5gr. It's fairly mild in a N-frame S&W.
4.5 gr of Red Dot did just fine today. Recoil is reduced from the 6.5-7 gr of Unique I was using. It was sooty but I consider most cast loads to be dirty in a handgun.
I will be using more in 44 special. And technically, I used Promo, not Red Dot. Same charge weights, different volumes. At 99 bucks for 8 pounds at the time it was a hell of a buy. I shoulda bought 3 or 4.
Even better news. I have been fighting this revolver and leading. Not much but a little just past the forcing cone. finally found a combination that doesn't lead.
NOE 503 cast form range scrap and air cooled. Lube with BR and size to .4315. Load with 4.5 gr of Red Dot.
I have used the same bullet and alloy sized .432 with a couple loads of Unique. It leaded a small amount.
I think that slightly smaller size and the quicker pressure spike did the trick. Lube ,at have made a small change but I doubt it was a huge factor.
Now I need to get busy and cast a heap of those bullets.
I tried super hard to convince my little Bro. into getting that same pistol when he got his concealed carry.
he opted for a Taurus in 40 cal.
then when I 'broke' it for him [told him I was doing him a favor] oddly at the same time I 'broke' my pt-92.
he finally opted for the bulldog and hasn't looked back, it's been 15-20 years now and he has had it with him almost everyday since then.
and the 7.? grs of unique [in my case .2] under the 429241 shoots well in a little heavier revolver but it still stings a bit depending on the grips and where your fingers line up with the hammer shroud.
I have shot a bit of 6.9 gr Unique with the NOE 503 and in the 624 it does let you know it is something. Recoil isn't bad by any stretch but you know you are shooting a larger bore revolver.