Advice on H4831sc powder please

[Goldfish]

I have a .243 and am using H4831SC powder in Lapua cases with Speer 100 grain SP (code 1220).

I have done some test groupings and find 45.5 grains of powder works for me

I have looked at the Hodgdon site which states the max load should only be around 42 grains of powder.

What do you think, am I pushing things too far?

 

This site identifies 44.9 as a good load with 100 grain heads????

 

http://accurateshooter.net/Downloads/sierra243win.pdf

[Guest northernchris]

Every rifle is different Luke,is it showing any signs of pressure??? stiff extraction,excessive head expansion,loose primer pockets etc

[Andrew]

No. The site does not say that is a "good" load. It says it is a MAXIMUM load. All rifles are different, as Chris said, but exceeding the powder manufactures recommendations by 10% is a foolhardy practice. Have you chronographed your loads? I'll bet there is hardly enough velocity difference between a safe load and one over maximum to justify the powder and the wear and stress on the rifle. ~Andrew

[Guest 308Panther]

I ran it thru Load from a Disk,just for my own curiosity and amusement,

and to familiarize myself to the program

Using a 24in barrel

Effective barrel length of 22.39

 

Charge weight of 43.001 (grains)is at 90% load density and is the highest safe load listed.

velocity is listed at 2820fps(muzzle)

Chamber pressure in CUP is 43,738.

Chamber pressure in psia 50,934

 

Charge weight of 45.401 (grains) is at 95% load density and is listed as "Danger"

Velocity is listed as 3041fps(muzzle)

Chamber pressure in Cup is 48,757

Chamber pressure in psia is 59,280

 

Optimal

Charge weight 39.0(grains) 81.7% load density

Velocity 2612fps

Chamber pressure in Cup 35,978

Chamber pressure in psia 39,462

 

Subtracting the 90% load from the 95% load.

I would think that is a real big jump in pressures for 221fps

 

308Panther

[Ronin]

Its really interesting the advice one gets from the forums, especially when that advice is sound and based on reference material not "own findings"

 

Firstly you have to remember all rifles behave differently no matter if they are the same calibre, model number and brand.

 

Everyone here has advised that you are above max load or near to it, I thought I would firstly check my own copy of Sierra 5 reloading book and see the following data:

 

H4831SC / 100g bullet - Start load - 38.0g = 2500 fps

 

Max load - 44.9g = 3000 fps

 

 

So on Sierra data you are .6grain over MAX load

 

Ive just entered the data into Quickload for your stated parameters (sorry i dont know your barrel length - I used a 26")

 

H4831SC / Speer 100g (1220) - 45.5g

 

Now Quickload shows the load to be yellow (warm but ok)

 

MV is estimated 2960fps

 

I have increased the load untill it shows red (over pressure) and find that 48.1grains is the predicted - (note PREDICTED) MAX before over pressure with 4831SC

 

 

Now I am not advokating loading your cases with any more powder - I don't know how experienced in reloading you are, the nature of your posts suggests you may be staring out (apologies if I am wrong)

 

If your cases with that load show no sign of pressure (flattened primer, cratered primer, hard extraction, extractor marks of case head, brass flow at the extreme)

 

Then if these are NOT PRESENT, I would SUGGEST this load may be safe in YOUR rifle.

 

If you are not sure, dont use it, try another powder or start at 10% less than stated max load in a handbook (dont rely on the internet data to be telling the truth now ) and work up slowly in .5 / .3 grain increments untill you find a safe and accurate load.

 

 

One other consideration is that load data printed now is 5 - 10 % more conservative with MAX loads than they were 5 - 10 years ago - I'd be interested to see what the max load for this powder is in an older manual if anyone has the time or inclination to have a look.

 

 

JMHO

[Goldfish]

Thank you all for the very comprehensive advice.

The load is one an experienced shooting friend used so thought I would try it.

The cases and primers etc are all fine but think I will re-read your responses and start some load development from scratch.

Yes, I am new to reloading so thank you all again.

[Redfox]

It also depends greatly on the make of case and the primer used, both of which can raise the pressure dramatically.

Also the powder manufacturer tests every batch of powder made and reccommends the max load based on the findings of those tests. The materials used and the factory where the powder is made, particularly in the case of Hogdon is completely different than ten years ago, which is why the change in load density ( even the air temp and humidity where it is made has an effect) rather than just being more conservative.

The most reliable info is from the powder maker, not a website or "your mate down the road", they have a vested interest in not blowing up customers but getting the best performance out of the powder in order to sell it.

 

I have developed good loads with 4831 in the 243, but the recognised best powder in that cal is 4350, either Hodgdon or IMR ( now both part of same company) the loads are NOT interchangeable though, use the load given for each brand.

There is no need to chase maximum velocity in this or most other calibres, the most accurate load is usually below the absolute maximum and those extra few fps are burning your barrel out faster, costing you more and at all normal ranges make little usable difference to the point of impact.

Cartridge: 243 Winchester

Load Type: Rifle

Starting Loads

 

--------------------------------------------------------------------------------

Maximum Loads

 

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Bullet Weight (Gr.) Order BW Powder Bullet Diam. C.O.L. Grs. Vel. (ft/s) Pressure Grs. Vel. (ft/s) Pressure

 

--------------------------------------------------------------------------------

 

100 GR. SPR BTSP 100 H1000 .243" 2.650" 44.0 2876 45,700 CUP 47.0C 3000 49,800 CUP

100 GR. SPR BTSP 100 H4831 .243" 2.650" 39.0 2761 44,400 CUP 42.0 2924 50,100 CUP

100 GR. SPR BTSP 100 Hybrid 100V .243" 2.650" 40.0 2868 45,400 CUP 43.7C 3100 51,700 CUP

100 GR. SPR BTSP 100 H4350 .243" 2.650" 37.0 2806 45,100 CUP 40.0 2973 51,000 CUP

100 GR. SPR BTSP 100 H414 .243" 2.650" 37.0 2800 44,500 CUP 40.0 2963 50,600 CUP

100 GR. SPR BTSP 100 H380 .243" 2.650" 34.0 2639 43,600 CUP 36.0 2770 50,100 CUP

100 GR. SPR BTSP 100 Varget .243" 2.650" 31.0 2674 42,700 CUP 33.7 2838 50,400 CUP

100 GR. SPR BTSP 100 H4895 .243" 2.650" 31.0 2683 44,900 CUP 33.0 2818 50,100 CUP

 

 

NEVER EXCEED MAXIMUM LOADS

www.hodgdon.com is the website, these are from there, just copy and paste into word and the columns will line up again or get them youreslf from the site, you will see that slightly less H4350 gives slightly more velocity still well within the max pressure.

Choice is yours but I can only repeat the powder maker knows best, the bullet makers do not retest test loads until a year or longer again ( there are some exceptions to this but not many as testing combos costs a lot of money) and the bullet maker is not responsible for powder variations.

Redfox

[Vermincinerator]

Hi goldfish.

There are more suitable powders for the 243 then 4831SC, IMO this powder is a tad too slow.

Like Redfox said 4350 is a top notch powder for 243 but go for the extreme version.

Personally i had excellent results with Win 760.

 

Ian.

[325WSM]

Firstly may I offer a word of advice by reiterating what others have said as it really is important.

 

NEVER use someone else's load but ALWAYS drop 10% and work back up and if you are in any way a novice stay a grain or so under max rather than pushing too hard - you need experience to judge possible pressure signs.

 

Ronin is correct in saying earlier manuals offered higher maximums but that doesn't necessarily make todays maximums something to ignore.

 

I had a Rem 700 Mountain rifle in 243 back in the late 80's early 90's and loaded H4831 for that.

 

The manual showed the following....

100grn Min 44gr at 2807fps and 42600 CUP and Max 46grn at 3071 fps and 47400 CUP

 

I shot Nosler and Speer.

 

For Nosler 100gr (30390) I used 45grn in Summer and 46 grns in Winter

and for Speer 105 gn (1229) I used 44.5 grn all year round.

 

When the SC became available I interchanged the loads (after testing) and could add a grain to the winter load with Nosler 100gn without any pressure signs or excess velocities.

 

However my wife shot a rebarreled 243 Mauser 98 in a Sporting stocked conversion and if I had used that load in this then I believe it would have blown it up. That showed obvious maximum at 4 grains less.

 

Every rifle is different and a simple change of primer can take you over the limit so any change = more testing.

 

A good guide to max if there are no other pressure signs is Factory ammo velocities. NEVER exceed factory ammo velocities and with no pressure signs you should be ok.

 

Remember you can always have your loads tested at the Proof House.

[Redfox]

Thats good advice lads and 325 WSM thankyou, I had forgotten to mention the proof house testing which is a very valuable point and gives absolute reassurance that you are not getting into the red zone.

Redfox

[Goldfish]

Thanks guys.

I have dropped my load to 39 grains today and put a few through to test aim point at 100 meters, it didnt change.

I am now loading some batches from 38 to 44 grains to play with at the range.

I dont do any longrange stuff so I think I will drop down to around the 39 grain load, test shots allowing.

Thanks again

Goldie

[Guest rogern]

Glad to hear that Goldfish.

 

Never use someone elses load