Home Forums Reloading Big Game Rifles Last bit of powder and bullets

Still a newb hand loader but understand the “working back up” principle when changing powder lots. Thing is I haven’t seen this situation addressed before.


One of the first powders I started out with was an older 1lb metal can of W760 that was given to me along with a box of Sierra 6mm 85gr HPBT’s. Turned out my first deer rifle that I’ve had for 40 years shot that combination better than any factory 100gr load I’ve ever used. I’m down to the last 20 bullets but only have a few hundred grains of powder left in the can. I have another 1lb plastic can of W760 that’s been around awhile as well, plus a newer pound of H414.

Load I’ve been running uses 42grs. If I finish out the can I’ll end up with 15 or so bullets left and will likely burn about half of them working back up.

Load data I used shows 42grs as max but I’ve seen others pushing this bullet harder. I just quit as I had good accuracy.

I’m considering three options:

1) Use up the 1’st can then work up with the 2’nd.

2) Blend what’s left into the 2’nd and work up from there.

3) Mix just enough of the 2’nd with the 1’st to use up the remaining bullets and working up.

I don’t use this rifle much so don’t plan to buy more of the Sierra’s, especially considering they’re hard to find currently. I have a chrono and a bullet puller so I’m half tempted to just load up a few at 42grs with the 2’nd can but know that’s not prudent. Main thing I’m trying to accomplish is saving as many of the remaining bullets for actual loadings and not development.


Thoughts appreciated and thanks.

.243 Winchester ?

Anytime you change a component you need to work back up. Do Not mix old powder in with the new powder. You will never be able to blend evenly. Back off your charge and work back up is the only safe way. You can use your bullets with the old powder and be fine with the old load. You will learn to stock pile your bullets, powder and primers for future use. Good Luck

Yep. Western Field M782, house brand Mossberg 800B for Montgomery Ward’s back in the day.

Pretty much where I was headed, just wanted to make sure I wasn’t leaving any reasonable options out.


I have a pair of .243’s and have put together a good stockpile. Thing was this one box of Sierra’s just happened to be in a box of components that my F-I-L had picked up years ago when he had thought about getting into it, but never did. I started out using up as much of the old stock as possible to get an idea of the process and it just worked out with this combo.

So you are 1/2 grain under the Sierra book Max.

Years ago I had a similar dilemma. .30-06, IMR4831, 180 grain Speer Spitzer, Fed 210.

Luckily I had the data where I had tried Hornady 180's, with the same lot of IMR4831, same primer, same shell case. I loaded the Hornady 180's with the new lot of powder got the same muzzle speeds at each increment as old lot. And away we went.

As to mixing in the last little bit of the old lot with the new? The book says no. Sometimes I cant find the book.

mag410;

Thanks.

Notes show I averaged 3077 fps @ 42grs, hoping it shakes back out.

Mix. and work back up. 100 grains aint gonna make a difference In a lb, or especially in 2lbs
You will probably end up the same
If I had 5 different lot numbers, I would mix them all and work up.
As long as you stay on the safe side.

Blend it. I’ve been blending the tail end of remaining powder into a new lot for decades.

I have a 12 liter clear plastic jug with wide mouth screw on lid. Given the state of powder availability the past 3+ years, twice I ended up with 3 different production lots of the same powder totaling 11lbs. I blended…..,

Mix it and work back up.

Powder manufacturers routinely blend batches of the same powder to get characteristics closer to what they want.

I would blend all the same powders to have one uniform lot, and work back up.

WW760, H 414, and AA2700 are basically all the same powder if you didn't know that...

about anything slower than IMR4198 works fine in a 243.

I just buy another jug of powder and keep on loading. I expect that there will disagree, but I’ve yet to see any difference from one jug to the next of the same powder. I also don’t load at the ragged edge of blowing the gun up like some folks choose to do.

I also never put anything into a powder jug that wasn’t there when I bought it. You likely won’t have any problems mixing the old with the new, I simply choose not to do it.

Seems there’s a consensus here, thanks all.


I did weigh the rest of the powder and there’s actually about 500 grains left so I’ll load up another 10 and then blend in what’s left into the other jug of W760 and work up. Worst case I use the remaining few for fouling shots.



@Seafire: Yeah, I knew that. You may not recall it but I had pm’d you about this exact load/rifle some time ago. It worked out much better than expected. I’ll keep the rest of the W760 and H414 separate given the age differences and keep working through the older stuff.

I have seen 6% lot to lot variation from a company that promotes 2% consistency. I have seen powder meet promoted velocity levels in some cartridges and be fully 300fps less in another cartridge with the same container.

As many have said, mix the powder thoroughly and drop back a grain, a half and 42gr. That's only 3 bullets used to compare where you're at for pressure and sighting. Any variance in pressure will not be enough to damage your rifle.