Does SO62 = IMR4320?

[Prof Young]

I'm preparing to load 30-06 with 175grain Sierra HPBT.

I've got Shooters World SO62 powder winging it's way to me even as I type.

According to Shooters World, SO62 is one of their recommended powders for 30-06. However on their charts I can find formulas for 168 grain and 180 grain, but no 175. Hmmmm . . .

Also according to their charts SO62 is an "equivalent" to IMR 4320. I can find formulas for the 175 using IMR 4320. (Lee handbook)

Given that I will stay at the minimum load, am I safe using the SO62 in place of the IMR4320?

Or is there way I can convert the formulas for 168 or 180 grain bullet into a formula for 175 grain bullets.

TRUST ME THAT I'M DOING NOTHING YET. WANT TO BE VERY SURE ABOUT ALL THIS BEFORE I PROCEED.

So much to learn about all this.
Safety is key issue here.

Life is good.
Prof Young

[Jim Watson]

If they have data for a 180 gr bullet, you are not far enough off from a 175 to worry about.

[Marco Califo]

No. You cannot use 4320 data. Use SW data for 180 for your 175.

[brasscollector]

Are you loading this for a garand?

[Prof Young]

Yes. I am loading for a Garand. Would love to hear your advice.

Life is good.
Prof Young

Keep it to M-2 specs. Garands were designed to work with a certain pressure and too much and it can pound the receiver (crack) and ruin it. Too little and it can be sluggish and unrelable.

[brasscollector]

Sorry, I'd love to help but I would have no insight for your particular combination (powder/bullet). I have primarily loaded 150gr FMJ-BTs for mine over either IMR or H4895.
If the powder you ordered has a burn rate similar to 4320 it should work given the correct data to start with. What that is I couldn't say, you might have to carefully extrapolate from 30-06 data if you can find it (i.e. start 1-1.5grs below starting load). If I were loading 175/180gr in mine I'd take the lowest accurate node that cycled the action and call it a day

[Rod47]

Personally I would consider 4320 a bit on the slow side for the M1.

[USSR]

There is an axiom known by all the old time Garand reloaders; "no powder faster than IMR3031, no powder slower than IMR4320, and no bullet heavier than 180 grains".

Don

[hounddawg]

SO62 is also known as Shooters World Precision and is very close to Varget. I am not sure what manual you consulted but on page 57 of their load manual https://shootersworldpowder.com/wp-c...rld-manual.pdf it shows a load of 45 to 49 gns of SO62 for the 175 SMK in 30-06.

Looking at the manual for my loads that I have used Varget in they are virtually identical for the .260 Rem, 6BR, and .223

edit - I went a bit farther and looked at the Hogdon site and found the following for 30 -06 using a 175 Sierra HPBT

Varget - 45 to 48 gns
IMR4320 45.5 to 48.5 gns


which compares to the 45 to 49 in the SW/Lovex data, how these would work in a M1 I have no clue.

[Marco Califo]

Similarities in loading data does NOT equal inter-changeability of load data between powders. Use ONLY SW/Lovex data for SW/Lovex powders.
There is NO conversion factor or formula.

[hounddawg]

so what you are saying is the fact that the load data listed for that bullet/cartridge min the Lovex manual is for all practical purposes identical to the numbers for the Hogdon data is irrelevant. Okies. I guess the starting load of 45 grains of SO62 is somehow different than 45 grains of Varget

[Marco Califo]

No. My point is you cannot conjure load data from similarities. They are not the same powders. OP mistakenly was looking for a conversion factor. IMO it is dangerous to let him think you can convert values from one powder to another. HD is saying data is the same # of grains. That does not make them the same powder. Hodgdon does NOT publish data for Lovex/SW powders.

[ammo.crafter]

Marco is dead on. Take his advice.

[hounddawg]

Did you guys not notice I linked the data for that bullet and powder in question to the manufacturers load data manual. I just mentioned the data is almost identical to the Varget load for the same bullet and also to other Varget loads I use. I don't see where that could be construed into "just make up your own loads as you see fit" unless you just want something to argue about

[Marco Califo]

My concern is for OP and readers, and the nefarious voodoo mythical conversion factor for two different powders that does not exist. Ruffled feathers is better than a bolt in the forehead.

[hounddawg]

Ok Marco I will play

suppose you had 500 175 gn Nosler CC's and 8 pounds of SO62. Nosler data does not have SO62 listed and Lovex data does not have Nosler bullet data listed. However the Lovex does list a load for 175 gn Sierra HPBT's. Would you just sit there and wish or would you you use some common sense and load some ammo.

There is not book data out there for every bullet/powder combo that can be used. Book data only goes so far, in some instances you need to use some common sense to just figure out a safe starting point.

I do shoot lot of .260 Remington, one day I tried a book recipe for a new powder/bullet combo and found out it was way too hot even using the minimum load that Hogdon had listed. If I had used a little common sense and looked at the 6.5 Creedmoor data for the same bullet/powder I would have seen that it was too hot. If I had kept shooting telling myself well it is a book load and therefore good I would have blown my rifle up.

Lesson was learned and now I cross check any new .260 Rem loads against 6.5 CM data. You won't find anything in any book about that but since the CM has just a tad less case volume I can be pretty darn certain that any load data for it won't hurt my .260. If one or the other is significantly different from the other it raises a red flag for me. I have four loading manuals on the shelf and use every online source I can find when developing a load but at times I still need to consult forums and other hear say sources to verify a load or find a safe starting load.

The old start low and work your way up and remember the rule that says what works in one rifle/barrel may not work in the other needs to followed by everyone. Always use common sense be alert for pressure signs, even with book loads

[brasscollector]

Originally Posted by hounddawg

how these would work in a M1 I have no clue.

Garand loading data (as a general rule) starts and ends about 1-1.5gr lower/less than standard 30-06. Slower powders and heavier bullets may want to stay well under the max, which IMO is the case here.

[44 AMP]

Point #1

ALL loading data is developed in SOMEONE ELSE'S GUN!!!!

Point #2

"SIMILAR" is NOT "IDENTICAL"

Point #3

Garand op rods are expensive. The Garand is not a rifle for using handloads that boldly go where no data has gone before....

[Unclenick]

S062 is a little faster than 4320 in QL. Same charge weight under a 175 generates about 7% higher peak pressure with the S062 and about 20 fps more velocity but with a couple percent lower muzzle pressure, which would make it easier on a Garand op-rod than 4320 is. However, the model may or may not be from a typical lot, but this is a rough idea, at least.

[T. O'Heir]

"...Lee handbook..." Lee tests nothing themselves. They use Hodgdon data for Hodgdon owned powders.
There's buckets of 175 grain data on Hodgdon's site. Just happens to be they used a Sierra HPBT for their tests. Suggest you use IMR4895 or, preferably, IMR4064 for an M1.
"...you cannot conjure load data from similarities..." Exactly. There is no 'close counts' with anything to do with gun powders. There is for bullet weights though. And according to Lovex's(the German maker of S062) burn rate chart S062 has no relation to IMR4320. They publish 180 grain data that is to CIP spec and shows very high pressures at nearly 60,000 PSI. Don't think I'd use S062 for an M1 Rifle.

[Unclenick]

Explosia is the maker. Lovex is a brand name they own. On page 9 of their reloading manual, they describe S062 as:

"S062 High density, single base, tubular propellant similar to Accurate 4064 most suitable for 8 x 57 IS, .30-06 and other ball cartridges."

That's from the horse's mouth. No mention of IMR4320.

On pages 39, 40, and 41 of this load data they list data for 8 different 180-grain bullets, all of which include using S062. The pressures you see are for the maximum load only, and not the minimum load. The Garand doesn't mind full pressure (very strong receiver), but it does mind the op-rod being exposed to an excessive pressure impulse. Lowering peak pressure does not necessarily lower that impulse because the bullet is slowing down, giving the gas port longer exposure to whatever pressure is there.

I know that observation goes against a lot of conventional wisdom about Garand-appropriate loads being intended to minimize gas port pressure. I've run the gas impulse calculation from QuickLOAD data and found the weight of the bullet far more of a factor than whether the powder charge is full or not, with middling loads of the lightest bullets being easiest on the op-rod, but for 168-grain bullets and up finding the gas impulse applied to the gas port is greatest in the low-ish to middle range loads that most Garand owner load to, and is actually smaller at higher pressure because even though the muzzle pressure is higher, the bullet is going enough faster that it shortens the time the gas port's exposed to it more than the pressure has grown.

The above was confirmed in actual gas port pressure measurements made by garandgear.com's engineer, Chris, who devised their hollow gas port plug. He measured pressure in the gas cylinder produced by increasing loads of IMR 8208XBR, and the hotter the load, the smaller the gas cylinder pressure was. So I think the medium load wisdom was always based on historical military loads combined with how the shooter imagined the pressure relationships worked out, but not on measurements.

[hounddawg]

am I the only one that knows that Lovex Powders markets in the US under the Shooters World label and SO62 is also called Precision Rifle


The Shooters World Reloading Guide for center fire ammunition was created as a
manual for reloading of Shooters World branded LOVEX® smokeless propellants
manufactured by EXPLOSIA® Company.

PRECISION RIFLE S062 RELOAD DATA


here is the data for the exact bullet and powder the OP requested - page 57

30-06 Springfield Winchester 175 gr Sierra SMK 3.32 45 2533 49 2714 59,900

as far as the M1 Garand part I would think that anyone that has loaded for one before knows to they need to adjust the charge

There may be some sites and data books that have data specifically for the M1 which is why I made the statement in my first post where I linked the data that I did not know if it was applicable to the M1

[Unclenick]

Nope. The OP said: "I have Shooters World S062", so I just assumed he did the translation.

[hounddawg]

so why is everyone including the OP referencing the Lovex load guide and the 180 gn bullets instead of the Shooters World load guide which has the info on the bullet he is using?

[Unclenick]

I don't think it's an exclusion. I think the OP either just missed that load on page 57, or it is the fact that it and none of the other S062 loads are labeled "Garand Load" like the one on the bottom of page 50 has put him off. I don't know.