I need loading information on the 400 whelan improved with 300-350 gr jacketed or leads bullets. Thanks,Kalamity

this is for the 400 whelen:
300 JSP IMR IMR-3031 60.0 2,265

350 JSP IMR IMR-3031 57.0 2,100

This is for the 400 Brown Whelen:

300 Barnes Spitzer IMR IMR-4198 54.0 2,373

300 Barnes Spitzer IMR IMR-3031 55.0 2,050

300 Patriot RN Alliant RL-7 55.0 2,345

350 Barnes X Accurate Arms AAC-2520 59.0 2,130

not exactly a 400 Whelen inproved but might be starting points.....these are max loads BTW.

411 hawk w/300gr Northfork and 63gr H4895 (max load) @2500 fps. Very accurate!

I am shooting the 400 Whelen Improved (40 degree) as well.

Barnes X 300 grain bullets, 57 grains AA 2230, 2500 fps (actually, more like 2460 to be precise). This is the only rifle that I have that shoots Barnes X (not TSX) bullets accurately.
I am able to use up to 58 grains AA 2230, but with some primer flattening at that weight, but no other signs of excessive pressure.

Here is another oddity: the rifle will shoot the 325 grain Barnes X with the same load (57 grains), without any signs of pressure either.

Swift A-Frame 350 grain, 55 grains AA 2230, at 2300 fps. Once again, 56 grains is tolerated in my rifle, but with some mild primer flattening.

I learned a few things from shooting and reloading this round: IMR 4064 and RL-15 are just too darn slow for this case. You can fill it up to the top and still not get your best velocities.

I haven't yet had the time to work with IMR 3031, but I suspect it will be an excellent choice for this round.

You are going to love what this cartidge does in the field. I took mine to Africa, and couldn't have been more pleased.

Please let us know how it does. The 400 Whelen deserves wider use.

Garrett

As far as most velocity for a given pressure (300 to 350 grain): in order

AA2230
BLC-2
H4895

Never played with cast.