need another h4350 vs imr4350 thread

fogducker

fogducker

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tried to search for info i needed but:...............
well lets say i tried...
ok right to it...
normally for my reloading for my 760 remmy..i always use a 180 grain bullet with 55 gr of h 4350..
but for the last few times trying to get this powder it was unavailable..
normally with my the h4350..my books say use between52 to 57.5 gr..but i always stayed at 55..
but as i was getting low on ammo..i bought a lb of the imr 4350..
my book states use 53 to 56.5 grs of powder..
i thought what the hell i,ll just stick with the 55 gr that im use to,as it was within tolerence of the low and high scales..
but what i noticed when despencing the powder that if i wanted to use 55 gr of imr powder...
it took up a bit more volume of room in the casing..almost to the point of a compressed load..
i double checked the scale with scale weights..and its all ok..
i guess im just second guessing my self on this...
am i good to go?
thanks ahead for any input here

Don
 
The two powders are virtually identical in burn rate. Numbers 91(IMR) and 92(H) on the chart. However, they're still slightly different and you should work up the load, not just pick one, again.
 
sunray is right, you really should work up the load, however, as the load you are using is 3% under max, and we know the powders burn very much alike, you are likely going to find you are OK.
Tod is right about the volume thing.
Can I talk you into making up just a few test lower powered cartridges. Doesn't take much to weigh out ten rounds or so, and be sure. Ten rounds is not a proper work up, just insurance.
 
I was told that H4350 generates lower pressures than the IMR. Is there any real data to confirm this?
 
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So I checked out that wesite and according to their data

30-06 150gr Nosler bullet

H4350 56 gr @ 37,100 CUP

IMR 4350 54 gr @ 47,400 CUP

I gather it is not just heresay, thanks for that fogducker.


As for working up loads till it indicates overly high pressures with both, not really what I like to do to my gun. I'll just believe the data and stick with the H4350 and load it with the loads I have worked up to already.

It is sometimes getting hard to find H4350 so I stockpiled some.
 
corney said:
As for working up loads till it indicates overly high pressures with both, not really what I like to do to my gun. I'll just believe the data and stick with the H4350 and load it with the loads I have worked up to already.
Click to expand...

I'm curious to know then how you work up your loads. Sometimes published loads are heavily overloaded in some rifles and under loaded in others. Published velocities can sometimes be met and exceeded and in other cases they cannot. I was not and am not suggesting you do anything dangerous, but follow normal and safe load development procedures.
 
Boomer said:
I'm curious to know then how you work up your loads. Sometimes published loads are heavily overloaded in some rifles and under loaded in others. Published velocities can sometimes be met and exceeded and in other cases they cannot. I was not and am not suggesting you do anything dangerous, but follow normal and safe load development procedures.
Click to expand...

I guess I came across wrong, I usally end up somewhere is the middle. I never load to the max. I'm sure you weren't suggesting that I load dangerous.

I buy better bullets instead of more powder.
 
corney said:
So I checked out that wesite and according to their data

30-06 150gr Nosler bullet

H4350 56 gr @ 37,100 CUP

IMR 4350 54 gr @ 47,400 CUP
Click to expand...

Correction, the "data.hodgdon.com" page for .30-06 indicates that 54 grains of IMR 4350 generates 47,400 PSI (not CUP). So the differences in pressure aren't as big as they might appear. While there is no direct means to convert CUP to PSI or vice versa (see innumerable writeups on the hows and whys), it's often the case that a pressure reading in PSI will be 7,000-10,000 bigger than it would be in CUP. So the pressures indicated for both the starting loads and the max loads for IMR4350 and H4350 are pretty comparable (as are the velocities achieved).

All other things being equal, H4350 does tend to be a touch slower than IMR4350 (though you may well find that a "quick" lot of H4350 might be quicker than a "slow" lot of IMR4350...)
 
I stand corrected. I just assumed it was in cup as that is how I knew it to be measured. I would very much like to learn what the difference between PSI and Cup is. You mentioned this has been debated before, on this site?

I will have to look into that.

Thanks Daniel.
 
Can't recall if its been gone over here or not. Googling "difference between PSI CUP", I had a look at a few of the hits, and based on briefly glancing at them thse aren't obviously wrong:

http://www.thefiringline.com/forums/showthread.php?t=207765
http://www.shootingtimes.com/ammunition/ST_cuppsireloaddata_200905/index1.html
http://forums.handloads.com/forum_posts.asp?TID=6833&KW

The last link includes a link to a .pdf article by Denton Bramwell, which is somewhat technical, but pretty good:

http://www.shootingsoftware.com/ftp/psicuparticle2.pdf
 
My "test" load for accuracy on any 30-06 has always been the 180 Hornady FB Spire point and 55 grains of IMR 4350. I have never run into a 30-06 that will not digest this load safely. Most '06 rifles are at max with the 180 somewhere around 58 grains of IMR 4350. [don't use this without approaching from below!] Regards, Eagleye.
 
Either one is great for the .30-06 with a 180gr bullet-but work up your loads.

A number of yrs ago Higginson powders was selling a lot of VV N160 powder which Hodgdon was using as an OEM propellant under their H4350 label. I recall this was around $14/lb and it turned out to be accurate and safe at 55gr with a 180gr bullet in MY '03 Springfield sporter.This pretty much matches what I found with IMR 4350.

There are better propellant choices than a 4350 for a 150gr bullet. A considerably lower weight of IMR 4064 or 4895 will get you ample velocity and accuracy with a lot less sound and fury than will a 4350.
 
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