My speer reloader book shows 32.0gr.max for the 400gr.speer fn & 1536FPS in the 45-70 in a #1 ruger using SR4759 powder.
It also shows in the same book and the same 400Gr. bullet in the 458win.mag. 30gr. max for 1445FPS.
Why doesnt the 458wm have a higher max load with this powder & bullet combo?
I tried a few at 30gr.max and had zero pressure signs and the primer was no where near flat..Would like to take it a little higher at lest a couple grains...anyone have any experiance with this powder and the 458wm/400speer combo?I would have thought that the 458 can take whatever the 45=70 can handle?

My guess is this is simply a REDUCED safe load. Not a max load for the powder. The loadtech program shows loads up to 62,000 for 4759 and they are MUCH bigger. Matter of fact I can't even fool it to go that low. I would suggest you get someone with Quickload to give you some info.

My OLD Speer #9 manual shows the 30gr for the 458wmag and 34 for a #1 45-70 and 28gr for a marlin 45-70.

IMR's handloader guide from 2002 shows
458 wm-510 gr sp-sr4759 44.5 grs-1645fps- 52.4kCUP

45-70-405gr-sr4759 29.0grs-1500fps-26.9kCUP
for the trapdoors

I've shot 40.0 grs with a 500 grain cast in 458 gave 1600+ from 16.5 inch barrel, accuracy wasn't very good

quote:

458 wm-510 gr sp-sr4759 44.5 grs-1645fps- 52.4k

Just as a comparison Loadtech calls 43.7grs max with a 500gr velocity a little lower. For a 400 it is several grs higher still.

quote:

Originally posted by ramrod340:

... I would suggest you get someone with Quickload to give you some info.....

I have Quickload v3.3 and I would be helpful; unfortunately it doesn't carry any data for the SR4759.

quote:

Originally posted by blackbearhunter:
My speer reloader book shows 32.0gr.max for the 400gr.speer fn & 1536FPS in the 45-70 in a #1 ruger using SR4759 powder.
It also shows in the same book and the same 400Gr. bullet in the 458win.mag. 30gr. max for 1445FPS.
Why doesnt the 458wm have a higher max load with this powder & bullet combo?

No rhyme ,no reason. Just happens to be where someone stopped. The .458 will handle more of any powder than the 45-70 with the same bullet unless the OALs are completely unreasonable. roger

quote:

I have Quickload v3.3 and I would be helpful; unfortunately it doesn't carry any data for the SR4759.

That is a shock. I just checked their sight and it isn't listed for ver 3.4 either.

If you are just curious substitute 4227 in the software and you might get an rude approximation.

quote:

If you are just curious substitute 4227 in the software

Loadtech has 4227 consistantly 2 grs higher.

If the 458 can handle 44.5grs Sr4759 with a 510 gr. bullet,can it handle that same charge with a 400gr. bullet?At the 30gr.charge iam getting killer accuracy and no recoil to speak of,I would like to take it up a few grains but dont want to be unsafe...the numbers just dont seem right,44.5gr.with a 510gr. bullet would seem like a lot more pressure?than with the 400gr.or am i reading this powder/bullet weight/pressure combo thing all wrong?
Seems like with all the other powders and bullet weights,the lighter the bullet the more powder charge it can take....??
Of course i would take it slow and in 1/2 grain increments until i started to see over pressure signs... just a few grains to get me going around 1750-1800fps neighborhood...somewhere around 35-38gr.?Does this seem like a unreasonable no- no?

Sorry but a full max load at 62350psi is only reading 1865 that is a load listed as 49.5grs.

If I wanted those velocities I would look for another powder.

WoW,Thanks a lot,I agree,I think i will try another powder for sure! Great Help!!

chuck hawk 458 link

http://www.chuckhawks.com/458Win.htm