Imr 4831

S

shanedapane

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Manitoba
So, I have finally run out of n570 for my 300 win mag. Still have 65 cartridges ready to go.
200 grain eld-x
71 grains of n570
210 federal primer
Hornady brass
2780~fps

In the meanwhile I've been playing around trying to figure out my next load as I have been told not to expect any n570 for quite some time.

A ladder with imr 4831 has suggested 70-71.5 is where to start. 3 rounds each, .5 grain increments for the load range.

Took 10 cartridges out with my chrono. 5x 70.5, 5x71.5. I didn't end up shooting the 71.5 because I was getting 2965~ fps with 70.5 and the book I am going from is saying 72.5 should be around 2850 fps.

Not seeing pressure signs, but if speed is above calculated pressure should be too...

Data is written with a 24" barrel, I'm shooting 26". Am I rightfully concerned, or should I just keep sending it?

This gun sees 10-30 rounds a year, my primary hunting rifle.
 
Dan, is that solid or jacketed? I see lower powder numbers in the solids and match grade data.

Lastgun, really the only thing I'm worried about is bringing my rifle home and having to tell my wife I f***** it up. Where I was set up, the chrono and I were out of the wind but it was a little too gusty downrange to check in on what it's like at 200. Fingers crossed as this is a way more versatile powder than 570, for everything we're shooting.
 
shanedapane said:
Dan, is that solid or jacketed? I see lower powder numbers in the solids and match grade data.

Lastgun, really the only thing I'm worried about is bringing my rifle home and having to tell my wife I f***** it up. Where I was set up, the chrono and I were out of the wind but it was a little too gusty downrange to check in on what it's like at 200. Fingers crossed as this is a way more versatile powder than 570, for everything we're shooting.
Click to expand...

Jacketed. If youre showing no pressure signs, go for it. But I would check a few different manuals first. - dan
 
Nosler reloading.com says 71gr imr4831 should go about 2932fps w 200gr bullet out of a 24” barrel. And that’s their suggested max. So you’re in the ball park with that longer barrel. But you might be on the ragged edge of max load. If you’re shooting and the ammo is cold that’s in your favour, and if you use that same load at warm to hot temps in the summer you might have trouble. What I would do if in your situation, continue with your ladder testing and be very careful, watching carefully for pressure signs. Keep track of where your best group is and that will likely be your sweet spot. And go down in powder charge as well from where you are now, to find that accuracy node.

I’ve found similar discrepancies as what you’re finding in different publications. So that’s why we should always check a few sources and come up with an average and work up from there. Having said that I really like the Nosler book, and now that it’s free and online that’s another bonus in our favour. And in the loads that I’ve developed I’ve found Nosler to be the most true to real life of them all. If you haven’t already, check them out. And if you have the powder they recommend as most accurate in their findings, start with that one. In the case of what you’re working with, it’s H4831.
 
dan belisle said:
Hornady calls out 56.2-64.8 gr of IMR 4831 for 190 gr bullets. 10 gr more bullet weight and 7 or so more grains of powder seems a tad high. - dan
Click to expand...

The Hodgdon data center online gives 69 to 72.5 compressed for that powder and 200 gr Nos Part bullets at 60,900 psi. max. Where did you find the other data Dan? My Hornady book is a little old and does not have IMR4831 listed for the 200 gr. Is the ELD-X that much harder to push?
 
270 totheend said:
The Hodgdon data center online gives 69 to 72.5 compressed for that powder and 200 gr Nos Part bullets at 60,900 psi. max. Where did you find the other data Dan? My Hornady book is a little old and does not have IMR4831 listed for the 200 gr. Is the ELD-X that much harder to push?
Click to expand...

Hornady #7. 190 gr BTSP. I have a few others (manuals, ok, more than a few), but that on happened to be in my office. - dan
 
270 totheend said:
The Hodgdon data center online gives 69 to 72.5 compressed for that powder and 200 gr Nos Part bullets at 60,900 psi. max. Where did you find the other data Dan? My Hornady book is a little old and does not have IMR4831 listed for the 200 gr. Is the ELD-X that much harder to push?
Click to expand...

Hornady #8 says the same. - dan
 
Each rifle is quite different, but, as you point out, velocity and pressure are surrogates.

If you do not have any pressure signs, you have a load.

However, in warmer weather pressures would be higher.

When i develop a target or hunting load, I test it with a half grain more powder, to verify I have some lee way.
 
shanedapane said:
So, I have finally run out of n570 for my 300 win mag. Still have 65 cartridges ready to go.
200 grain eld-x
71 grains of n570
210 federal primer
Hornady brass
2780~fps

In the meanwhile I've been playing around trying to figure out my next load as I have been told not to expect any n570 for quite some time.

A ladder with imr 4831 has suggested 70-71.5 is where to start. 3 rounds each, .5 grain increments for the load range.

Took 10 cartridges out with my chrono. 5x 70.5, 5x71.5. I didn't end up shooting the 71.5 because I was getting 2965~ fps with 70.5 and the book I am going from is saying 72.5 should be around 2850 fps.

Not seeing pressure signs, but if speed is above calculated pressure should be too...

Data is written with a 24" barrel, I'm shooting 26". Am I rightfully concerned, or should I just keep sending it?

This gun sees 10-30 rounds a year, my primary hunting rifle.
Click to expand...

Standard or Magnum primer? I've had the understanding that once you exceed 60gr of powder, magnum primers are the way to go or is that just another old reloaders tall tale?

Data from Hornady #10 for a 200gr ELD-X & IMR 4831 would suggest your a little warm with that bullet/powder combination. Run your cartridge data thru Gordon's Reloading Tool with N570 & IMR 4831 and compare.
Looking at the data below, 1.3gr more powder + a 26" barrel I can see you getting 2965fps.
RCJAXfal.jpg
 
Ganderite said:
Each rifle is quite different, but, as you point out, velocity and pressure are surrogates.

If you do not have any pressure signs, you have a load.

However, in warmer weather pressures would be higher.

When i develop a target or hunting load, I test it with a half grain more powder, to verify I have some lee way.
Click to expand...

That's good advice. - dan
 
Appreciate everyone's responses and advice. Finally had a couple nice calm days, temps got up to -10 or so, nice and relative to deer season.

I had considered the part of winter vs summer with the load I mentioned, this rifle doesn't really leave the house until we hit 10-15 degrees in late September's elk rut.

Anyway, I had 7 rounds remaining from the first test, 10 at 69.5 and 10 at 69, and 10 at 68.5.
Very timely process, I've been waiting 3-5 minutes between each shot when checking grouping. 69 is down where I want to be (haha).

Still hugging 2930.
 
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