by Seismic Sam on Sat Aug 25, 2012 11:17 am
Well, just to post the caveats involved with non-cannister powders, there are several pitfalls which can bite you in the butt if you're not careful, and I'm glad you have a chrono so you can spot if the velocity on a worked up load shows signs of starting to spike, or the SD of the velocity goes all to hell at higher velocities.
Cannister powder, meaning the stuff we buy at places like Gunstop and Wolf's Den, are not merely produced and sold. Cannister powders are like blended Scotch, and they are made by mixing together different lots of powder to get the EXACT same burn and pressure characteristics, so that the user can rely on the fact that his max loads stay max and not OVER max, and the rounds he produces will shoot the same every time he loads them. Imagine what a mess it would be if your point of aim changed every time you bought a new can of Varget!!
Now, bulk powders are unblended, and each lot consists of multiple TONS of powder, and these are bought and used by ammunition manufacturers. To use an example I found out about after a conversation with the good folks at Cor-Bon, they buy a whole lot of bulk powder, and then develop a load for one or more cartridges using their chronos AND pressure barrels, and then run the whole lot of powder out making that ammo. The point here is that they are not reloading to a constant velocity, but rather a constant PRESSURE (which should give you uniform velocities), because Cor-Bon sells max pressure defensive ammo. The same is more or less true with max hunting loads in rifle and pistols - they are making stuff with the maximum hitting power and buyers may very well buy the ammo with the greatest number of ft-lbs or FPS velocity. (Yes, bullet choice is also a buying point, but we're talking powder right now.)
Now, pulldown powders are another step out into the weeds as far as consistency. If somebody has money invested in tens of thousands of rounds of some ammo that isn't selling well, or is too old, or something else, they may choose to harvest the value of that stuff by disassembling it and selling the bullet, powder, and cases. The thing to be wary of with pulldown powder is THAT IT CAME FROM SOMEBODY WHO DIDN"T WANT THE AMMO IT CAME FROM ANY MORE, and there can be a lot of reasons for that, some of which aren't particularly good or in your favor.
So; With pulldown powder you can't depend on it coming frome one lot, and you can't depend on it all being the same age, and you can't depend on all of it having been stored in the same conditions. The ammo could have come from +100F ammo dumps in Asscrackistan, or the ice covered dumps of Camp Ripley (up Nort dere..) in Minnezotah.
Your statement that "I was told to load it like H335" is NOT a statement of equivalence between wc844 and H335!! No way Jose!! H335 is a cannister powder, and your wc844 is Heinz 57 powder that came from God Knows Where and is "more or less like H335"!! Rather than a statement of equivalency, it is approximately equal to a signpost on a country road pointing you in the general right direction, but nothing more. It's up to you to use your chrono and careful load development to work up a load in sensible increments, and the max and min levels for H335 in some loading manual are nothing more than ballpark approximations with wc844.
So be careful out there!
