Sanity Check - 44 mag loads with Keith SWC 240 gr

[Jlr2267]

Ok, I ordered some hardcast SWC from Missouri bullet...they are harder than others I have used (~18 BHN). I am planning to use Herco at 11 grains to start, with a std large pistol primer.

The pressure w/this combo is ~33k, which is significantly higher than what is "ideal" for a bullet of this hardness. I know leading can result from low pressures, but do I risk leading if I am on the high end as well?

 

[rcmodel]

11.0 Herco will not be anywhere even close to 33,000 PSI with a 240 Keith.

That load will give you about 23,000+ PSI, and a little over 900 FPS out of a 4" barrel.

Suggest you start there and work up, and see what happens.

If you get to 13.1 grains, you might be getting 34,600 PSI & 1,090 FPS, according to Lyman #49!

rc

 

[Jlr2267]

11.0 Herco will not be anywhere even close to 33,000 PSI with a 240 Keith.

That load will give you about 23,000+ PSI, and a little over 900 FPS out of a 4" barrel.

Suggest you start there and work up, and see what happens.

If you get to 13.1 grains, you might be getting 34,600 PSI & 1,090 FPS, according to Lyman #49!

rc

My manual (Lyman 48th) shows 28,000 at 10.5 grains and 960 fps. At max load (11.7 grains) it shows 38,000 and 1100 fps. One of our manuals must be wrong

 

[rcmodel]

Must be.

My Lyman # 47 shows 10.9 start = 918 - 22,900 CUP.
13.1 MAX = 1,090 - 34,600 CUP.

But, lets not confuse CUP and PSI pressure measurement.

rc

 

[Jlr2267]

All my data are reported as CUP from Lyman 48th. I also looked this combo up in an old Hercules manual (1992) and found similar numbers (33,000 CUP at 11.5 grains)

 

[rcmodel]

Well that's Real Odd.

My 1992 Hercules manual shows 12.5 grains Herco giving 1,330 @ 33,800 PSI.

But with a lead gas-check bullet.

Not the plain base cast bullet you are talking about.

Too late to argue about it now, but 11.0 grains Herco is Not going to give you those kinds of pressures or velocities.

rc

 

[Rule3]

Either way or either or.The MBC 18BHN is hard enough to drive the bullet in a 44 Mag any way you want

I shoot them with max loads or H110 and 2400.(lyman cast manual)

 

[Jlr2267]

Either way or either or.The MBC 18BHN is hard enough to drive the bullet in a 44 Mag any way you want

I shoot them with max loads or H110 and 2400.(lyman cast manual)

Thanks, that's what I was looking for.

 

[Salmoneye]

My 1992 Hercules manual shows 12.5 grains Herco giving 1,330 @ 33,800 PSI.

But with a lead gas-check bullet.

FWIW

2004 Alliant Manual lists exactly the same...