Being relatively new to handloading, I was wondering whether anyone made it a regular practice to work up loads from scratch whenever new powder (same type, different lot) is purchased? I'm saving a little from the old lots I have, to check against the new lot using a powder dipper, so if the density varies, I'll know. But do you guys ever get a "hot" load of powder?

I know Pyrodex will supposedly "weaken" a bit if it sits for a while (even as short as six months), but smokeless powder doesn't change that much if it's within its normal temperature range while its stored. None of mine is even a year old yet anyway.

Thanks

Before I started buying powder in 8lb containers for magnum rifle cartridges I was very frequently getting different lot numbers. You only get 4-5 boxes of magnum ammo out of a can of powder. I've never seen a huge difference between lots of powder, never big enough to see for certain on a chrono when differing test conditions are taken into account. Unless you load your ammo on the ragged edge there probably isn't too much concern lot to lot. If you bought your last can of powder 5 years ago I might reduce loads a few grains when starting with the new can.

If you store your powder properly I don't think it degrades much if any over a 10 year period. I just shot up some WW452, WW473, ww540 (HS-6), and WSL that had price stickers on the containers that where well south of the $10 mark, which means they where very close to, if not, 10 years old. Shot most of it in shotguns, some in pistols....couldn't tell any difference between it and new, except those powders have all been discontinued.

AZ223,
I never worry about different lots of powder being very different from each other.I did have a can of IMR powder(I forget which)that gave better groups in my 270 then any other lot or powder combinations.
Other then that one case,differences,for me,are not worth devoting extra time to.I have a chronograph,so any differences will show up as more or less FPS.
Frank

Thanks, I kind of figured as much. I'm more cautious than some, but I need to get a chrony as I lean toward max loads with my .223 With changes in components I know enough to work it up, but was just wondering about powder variations.

I also read another thread on a different forum where a guy's gun blew up. :eek: This person habitually flirted with disaster, and it was his second such "accident" in a year. But still, you never know.

Thanks! :)

With our normally bone dry climate here, wouldn't be concerned with long term storage of powder/primers if kept in a dry and relatively cool place. (For those unfamiliar with Arizona, cool has a different meaning here than in most places!)

As kciH says, providing you're not bumping the max loadings, the difference will usually be pretty small between lots. Wouldn't hurt to make up 5 or so rounds with a new lot and try them before committing to large scale production.

Yes, a chronograph is an indispensible tool for handloading, especially if you intend to run up to the highest loads your firearm will accept with accuracy. A .223 can develop high pressures with just a tad of overload.

I have a 8Lb keg of IMR 4831 powder I bought over 25 yrs ago, never opened. I also have some 1lb cans from the same window. They all perform well, using the old loads I logged back then. However when compared to todays manuals my loads are beyond max. I wish i would have saved those old manuals. I suspect that the lawyers had a play in this, but also the powder today ie: IMR 4831 is a way different lot than my old keg.
Jim