375h&h

[trauma1]

Not real sure where to post this. I have a Remington XCRII. I have ordered some 250gr cast boolits. I have SR4759 available and have seen anything from 30gr to 41gr as loads. Is 37gr safe? Looking to get @ 1800fps out of them for deer/hog in florida.

[1Shirt]

Have never shot 4759 in my 375's, but my deer load is 28 gr. 2400 under 375449HP cast about 18-20BH. Goes around 1800, and is a bang/flop deer load out to at least 150 or so.
1Shirt!

[leftiye]

I've only gotten up to about 32 grains in mine with a 300 grain gas checked HP boolit. I haven't chronoed it yet. It is a mild load, doesn't kick much atall. But it is accurate, and reaches out nicely. I'm guessing 40 grains might be fine. Start at 32 maybe. Work up and do accuracy tests (shoot targets). Accuracy may go south before max pressures are reached. 1800 fps won't be hard to do. Great wabbit load!

[Nobade]

40 is plenty safe pressure wise, but 35 is probably going to be a lot more accurate. Start at 30 and work up until you get the best accuracy and no leading.

-Nobade

[Gleedaniel13]

40 is plenty safe pressure wise, but 35 is probably going to be a lot more accurate. Start at 30 and work up until you get the best accuracy and no leading.

-Nobade

I think its better to start at 35 to make it safe.LOL.

[Nobade]

35 may end up being your max load for accuracy. If it gives big speed spreads add some dacron fluff to keep the powder back against the primer.

-Nobade

[Three-Fifty-Seven]

AbcFPS

[trauma1]

that is what I mean. I have seen so many different loads with sr4759 that I am not sure what to believe. I guess the 32.8 to err on the side of caution

[Three-Fifty-Seven]

loads ...

[leftiye]

Lyman's #4 lists 32.8 grains of SR 4759 as max with the Lyman 375248 (249gr) at just under 1900 FPS

Thanks for the info. So, 2000 fps is within reach, probly safely too. I'll get flamed for this but I've always (45 years reloading) thought that lyman's cast boolit maximums had little to do with anything. In many incidences, I can't see how they relate to the real world with real guns and their strengths (what with cast being driven at industry maximum pressures so often elsewhere, and that being safely to boot). But, they probly are in the ball park for cast boolits and the lubes of 45 years ago. It probly won't matter anyway as accuracy probly won't rear its comely head at maximums anyway.

My son in law asked me how this load related to a full house 375 load, and I estimated it at 25% of industry maximum.

[Larry Gibson]

Lyman's"maximum's" were once based on accuracy testing at 50 yards. The maximum was reached when accuracy became unacceptable. I'mnot sure what 'unacceptable" was for Lyman. Does the RPM threshold ring a bell though? Most of Lyman's "maximum's" are prety close to where the RPM threshold would be with the powders used. They don't test for accuracy on target anymore but use internal ballistics measured by piezo-transducers and strain gauges to set the "maximum" now. Wouldn't surprise me if they also use velocity with many of their maximums as they still adhere to about where the RPM threshold would be.

Larry Gibson

[youngda9]

I can get 2209fps with a 232 grain 358 Winchester boolit with 1" accuracy at 100yds (5 shot groups). They are WDWW boolits with gas checks and 45/45/90 lube (dipped and passed through the sizer to fully fill the grooves) I don't see why 375 diameter bullet should be much different. 2000fps should easily be obtainable. I would suggest choosing the lowest pressure vs velocity powder you can find in the reloading tables for a 375 bullet in your weight range. This will give the best results IMO. I use 4895 for the 358win.

[trauma1]

this is killing me. I just need a straight forward answer as to what will get me to what I want. I do not want to blow up me or the gun either. The best I can find is 34gr max of SR4759 with a 250gr cast bullet. One would think that a 100+ year old cartridge that is considered to be the "best all around all over" wouldn't be this hard to figure out.

[NVScouter]

Since the cartridge has been chambered in every platform by everybody and is 100 years old is your answer.

[leftiye]

Start at 32 grains, accuracy test. Add a grain, repeat. Continue repeating until accuracy peaks and/or drops off. Use best load. Then go kill something.

See "pressure estimation" read pressure signs (flatness of primers, case expansion, case scuffing) while increasing loads. Take a walk on the mild side.

Then publish your results so I can use your load.

[Nobade]

Didn't I say that same thing last week? That really is how you do it.

-Nobade

[trauma1]

Last Question - Do I need a filler with SR4759 between 30-37gr? Would more than likely be using batting/stuffing if so. From my reading would think a 1-1.5gr tuft would suffice.