I am trying to find load or reload data for 5.56x45mm ss109 surplus bullets and wc844 powder. I have been using Ammoguide interactive, a good resource but not much info on wc844 powder. I am mainly looking for a how many grains of powder to use. Any information would be greatly appreciated.

It is loosely like H335 so use that for a starting load and work up.

This is, or is at least is adjacent to, one of the biggest misunderstandings in reloading.

As noted above, H335 is a canister grade powder that is roughly similar to WC844.    Similarly, BLC-2 is the cannister grade powder roughly similar to WC846.

Before we go any farther, pull up a powder burn chart now and note how many powders are listed in between H-335 and BLC-2.  Charts vary somewhat but you’ll probably find 20-25 powders listed in between them varying from H-4895 and IMR-4895, to IMR 4064, Accurate 4064, and Reloader 15, to Winchester 748.

I bring that up as WC846 was the standard powder for the 7.62x51 M80 ball load used in the M14 and M60 when the 5.56 M193 round was being developed and put into mass production.

They found that one end of the manufacturing specification for WC846 powder was well suited to use in the problematic 5.56mm round, and designated a new specification called WC844 from within that larger WC846 specification.

The point here is that bulk powders used by military armories and commercial ammunition factories are produced in 10,000 pound lots.  The manufacturer then develops specific load data for that particular lot of powder.


In contrast canister grade powders intended for Reloaders are developed to much tighter specifications.  But there is still some lot to lot variation.  For example it’s been well over a decade since Hodgdon stated that HP-38 and Win 231 are the same powder. As are H-110 and Win 296.  Hodgdon just sells them to Winchester which repackages them in cans with a different label.


But look at load data and you will find manuals that list different max loads and different max velocities for the “same” powder.  For example in the Hornady 11th edition under their .44 Remington magnum rifle load and rye 225 gr FTX, you see a max load of Win 296 of 21.3 grains and 1700 fps, right above a max load of H110 of 20.6 grains and 1650 fps.   That’s a .7 gr difference in maximum load, about 3 percent. That also about the same difference between the 1600 and 1650 fps loads.

An uninformed reloader given the choice and wanting the most velocity might be inclined to grab the can of Win 296 rather than H110 because he thinks it will produce a higher velocity and then load up the maximum listed charge. He’ll usually get away with it as the limits are suitably conservative and firearms are proof tested to about 130% of the expected maximum pressure.  But it’s still an ignorant approach.

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It gets far worse when a reloader gets a good deal on a surplus powder like WC844 or WC846 as they are bulk powders originally delivered in a 10,000 pound lot to a very wide specification.

Our hero then scours the internet looking for load data, often to produce a clone load of a military ball load. Sooner or later he’ll find a chart that shows a “nominal” charge weight for WC846.  Let’s say is 45.7 grains.  He then assumes he can load up 45.7 grains of his WC846 powder and get the specified pressure and velocity in his duplicate load.

Setting aside issues of differing case volume in military 7.62 versus civilian .308 brass (and how that has changed in the M118LR and M80 ammunition produced by Federal), the actual load he might need to get the velocity specified might differ by a couple grains in either direction. That creates the potential for him to develop a load that massively exceeds the maximum and or maximum average pressure standards.

It gets even worse if his surplus powder is pull down powder obtained by pulling bullets and then pouring the powder out from surplus ammunition.  The odds that all of that ammunition was made from the same lot of powder?  None. Zero. Nada.  

When colloidal bulk powders like WC844 and WC846 are made, ballisticians for DuPont, etc, mix different batches to get the desired burn traits to create the lot of powder that is shipped.   Mixing powder from those different production lots will not however necessarily produce an acceptable lot of powder.  Those mixed lots may also not be evenly mixed.

That puts the reloader using that pull down powder on the frontier of crash test dummy territory.


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I have used surplus powders.  However, I won’t use pull down powders.  When using surplus powders I start with a nominal load, reduce it by 10 percent and then work up to the desired or specified velocity using an appropriate firearm and a chronograph while looking for any signs of excess pressure.  For example for an M80 clone load using new sealed in the jug WC846 powder and military surplus or contract over run 147-149 gr projectiles, I will work the load up in my M1A, carefully measuring velocity with a chronograph usually using a 10 round average in the load ladder and then 30 round averages as I finalize the load, all while watching for excess pressure signs. For an 8 pound lot of powder it’s worth the effort.  For anything less, not so much.

Thank you, I will try that.
I am trying to get the feel back for posting. I was a member several years ago and over time I got rusty on the process.

I have been trying to figure this out for a while. I had heard before about it being similar to H335 but I always question it. I like the idea of reducing by 10%. I felt the deal I got on the wc844 was pretty good but I don’t want to damage anything because of a good deal! And 8 lbs of powder not being used is not a good deal.
Where can I find data on the wc844 powder?

Having loaded a fair amount of both of those two surplus powders when they were available, I’ll give you my .02.

Absolutely follow the advice to reduce 10% and start there.

Also, if you don’t do it already, you’ll absolutely need to have a chronograph to see where you’re at when loading those.

Spot on. Reduce and work up, nobody can tell you which charge will be safe with your lot.  I like 844 (been through 48lbs in the last few years) but you need to work with it carefully.