Sorry- I use IMR7828 165 grs.with a 900 gr bullet. That's a stiff load for a .600NE but a mild one in the .600OK-Rob

I would not use Rl15 with cast bullets because they will end up going too fast. Instead I would try XMP5744 for a low velocity, low recoil load. This is just a guess, but probably about 50-60 grains of XMP5744 is the place to start. However, you may want to contact Accurate Arms, maker of the powder, to get their input.

Rob's IMR7828 may work OK with cast, but I would back off to 150 grains or so. I believe the problem will be poor powder combustion. Smokeless seems to need to achieve about 25,000 psi (more is better) to achieve a kinda clean burn. 500grains suggestion may be even better, I don't really know as I have never used that powder (I don't shoot reduced loads, sorry).

ASS_CLOWN

Another option is to just use a case full of 50BMG powder. It burns so slow that the pressure will be low. Just make sure it is a few notches slower than IMR7828.

Some quickload numbers, don't know if they work or not.

600NE 900gn cast 24" bbl

125gn RL15 1900fps @ 30ksi 81% load density - use filler-



Surplus IMR 5010 is $3 a lb

From quickload

160gns IMR5010 1630fps @ 22.9ksi



Just for comparison Quickload says Rob's load

165gn IMR 7828 2070fps @ 40ksi



Not load data, just numbers from Quickload.

thanks I was thinking about pushing the 900gr cast to about 1700fps. Would make a nice whitetail and hog load
Dean

Here is my 'standard' 600 NE load:

159 grains Re22, 900 grain Woodleigh FMJ, F215

But I would not use a lead bullet with that load because I like to keep lead loads down to 1500 fps.

Dan
Thanks I have woodlieghs also so ill add that load to my book. Do you think 1600 to 1700 is to fast for casts?
Dean

Tonto,

People with far more cast bullet expertise than me say that the limit with a cast is 2000 to 2200 fps, but to get there you need a really hard allow and the right magic lube.

I use cast bullets made by others so I am not in a position to control the alloy and lube. And I am a bit of a worry wart about leading so I keep the velocity down as much as possible. Just last week I developed a new 500 grain cast lead load with my 470 capstick that comes out at 1100 fps. It licks like a 38 special.

Which brings up another point, I like to use cast for low recoil practice. More velocity means more recoil, so again I try to keep the velocity down.

With all of that in mind, I think you can get away with 1600 to 1700 fps with the right alloy and lube. Or with paper patched bullets. Also, going that fast gas checks are going to help, particularly if you use a rifle powder like Re15. Rifle powders will tend to heat the base of the bullet and increase the tendendency to leave lead deposits in the barrel. XMP5744 does not do that.

So there you have it, my answer is MAYBE.

From Quickload for what it's worth
600NE 900 cast 24" bbl
115gn RL-15 1750fps @ 24ksi 75% load density.

Not load data, but seems reasonable to me with a filler.

I shoot 500gn gaschecked bullets in the 470NE to 2150 without a problem. I'm useing Javalina Lube. I'm sure the gascheck helps with the higher velocity.

By the way I use Linotype for all my modern rifle cast bullet loads. It will hold up to a little over 2000fps in most cases. I made my own .600 mold so no gas checks just a flat base.-Rob

I'm shooting water dropped wheel weights.
I don't even know if they make a .620 gas check?