proportional load work up 44mag

[farmbif]

in trying out some bullets from a new mold mp's 432640 gc, I got a good load with 20 grains 4227, but as 4227 is it leaves a lot of powder in the barrel.
yesterday I thought maybe I'll try some 300mp since I have a bunch of it. I referred to Brian Pierces nov 2011 work in handloader mag, since ive had good success with 358156 in 357 mag 17gr 300mp.
the bullets I'm casting are 275gr solids and hollow points ranging from 255 to 265 grains.
Brian starts 250 gr cast load with 24gr 300mp, but both 270gr and 300 grain jacketed bullets his starting load is 20 gr 300mp.
I tried one 275gr solid yesterday in the marlin at 20gr and had noticeable flattened Winchester primer but no sticky extraction. I'm thinking to back off to 19 gr powder.
am I on the right track here.

[farmbif]

I kind of knew I should have sold off some of this mp300 and bought more 2400

[megasupermagnum]

Are you refereeing to the +P data? Make sure you watch the OAL, I'm under the impression much of it is Redhawk/TC only due to the length.

Straight from the Alliant website for 44 magnum

270gr gold dot
Federal 150 (standard) primer
1.585" minumum OAL
maximum load: 22 grains 300-MP

It is also worth noting Hodgdon lists the same bullet with a max load of 21.5gr H110. It has been my experience that 300-MP is slightly slower than H110. I have not done any work in 44 magnum with 300-MP, however, I have not had any pressure signs with it in 357 magnum or 327 federal. I have also shot considerably heavier loads in 44 magnum with no pressure signs. It can be a tough call, but my 2 cents is that I really doubt you are over pressure at 20 grains of 300-MP with that bullet.

[fcvan]

Most of my high speed loads, albeit .357, 41 Magnum, and 45 Colt loads are generally Unique, but I have used 4227. I prefer Unique as I don't really push it. I have 41 and 45 carbines, and 4227 is remarkable. 41 S&W M57 is 8 3/8" and didn't notice any issues with 4227. I like Unique, I buy in 8 lb jugs. Well, 4227 as well.

[44Blam]

4227 is at or just slower than W296. I shoot a lot of 44 mag in W296 and it is very powerful. I like shooting it, but I watched someone shoot my revolver with that W296 load and I could see the power.

I love 44 magnum.

[fcvan]

I do too, however, I don't own a 44. My Wife, however . . .

[44Blam]

I do too, however, I don't own a 44. My Wife, however . . .

My wife likes shooting 44 mag in my Henry with the Trailboss loads. She's a damn good shot too.

[fcvan]

My wife likes shooting 44 mag in my Henry with the Trailboss loads. She's a damn good shot too.

I know I will need to get my wife a 44 carbine, she smiles so wide when she receives such gifts. Kind of like the day she saw her Ruger SBH 3 3/4" at a gun show. I told her 'new gun, new dies, molds' and she looked like I kicked a puppy. Then I reminded her I already had dies and molds for reloading because of a friend from work. "Get that gun" and her smile was like Christmas for a 5 year old. We found a commercial loader at the show, and she shot it that day.

She is a Ruger Freak! Okay, the first gun I gifted her was a Ruger, I guess I might have contributed to her fanaticism. When I built her an AR 15, I couldn't buy Ruger parts . . . save for the flip up sights I used in the build. Huge vibrant smile. Happy wife, happy life!