Changing lot #s

[wisconsinteacher]

I know that you have to back off a little and recheck the loads with a new can of powder but in your years of reloading are lot numbers of the same powders close to each other? I hit the sweet spot of 36.1 gr of IMR 4064 in my 22-250 and am out of powder. I also understand this is the reason for buying 8# cans but right now, that is not going to happen for me. How much have you seen or not seen in change between lots?

 

[DrMike]

The burn rates are often similar, or even identical. However, there are no guarantees. I have assuredly encountered more than once lots of powder in which the burn rates were greatly different.

 

[Antelope_Sniper]

If your last lot of powder was purchased in the last few years I wouldn't worry about it all that much. Ocassionally formulations are changes, or factories are changes, and in those cases you may see an bit more difference then usual. If you have a good load, and it's not on the ragged edge, I'd just go with that on the new lot. If it didn't perform as expected, then I work up. If you are shooting a max load, back off 3% and work up again.

When shooting surplus or other non-canister powders, always back off the full 10-15% and work up when changing lots.

 

[Guy Miner]

Varget had some pretty wild swings between lots several years ago. Well worth backing off and starting again.

Otherwise, I haven't seen big problems, and yes, I heartily endorse buying 8# jugs of your favorite powders!

 

[JD338]

For me, the IMR powdrs have been pretty consistant from lot to lot.

JD338

 

[bullet]

For me, the IMR powdrs have been pretty consistant from lot to lot.

JD338

+ONE, IMR will give you real consistent loads from lot to lot for the most part with very few exceptions.

 

[Antelope_Sniper]

Varget had some pretty wild swings between lots several years ago. Well worth backing off and starting again.

Otherwise, I haven't seen big problems, and yes, I heartily endorse buying 8# jugs of your favorite powders!

Guy, was that about the time they were moving production from Scotland to Australia?

 

[Oldtrader3]

I have been using IMR powders for almost 50 years and most certainly since they moved production to Australia, I have not had any issues with burning rate variations.

 

[DrMike]

I have been using IMR powders for almost 50 years and most certainly since they moved production to Australia,

Australia? Canada, perhaps? Can't let the Aussies take credit for one of the few things that we provide.

 

[Oldtrader3]

Sorry, not up to date. The last that I heard they were moving to Oz! I know where Valleyfield is, I just did not know that IMR had moved there!

 

[Ridge_Runner]

never had a problem with IMR, however I've saw over 200 fps change in the same load with different lots of re22
RR

 

[RiverRider]

I think that the instances where you have to move on to a new powder lot number are a great justification for buying and using a chronograph.

 

[wisconsinteacher]

RiverRider, I am saving up for a chronograph. By next spring, I will have one.

 

[RiverRider]

That's very good, teach.

When I started wanting one twenty years ago, I thought it would be the answer to all questions and that it was the very path to Nirvana. I would now be able to detect where that magic charge was---you know, the one where velocities only vary be 6 fps over a thirty shot string?

I was disappointed, to say the least.It didn't take me long to discover that for every question that was answered, three new questions would arise. I guess that the short story is that having a chronograph is not a pathway to Nirvana, but being able to get the general idea of where you're at in the grand scheme of the load development process is a very good thing.

A chronograph is a very good investment!

 

[nvbroncrider]

Love it!!

 

[SJB358]

Wow! Now that picture RR is too funny!

I agree, the chrono opens up 10 more questions for every one it answers sometimes.

 

[Oldtrader3]

The path to enlightenment is littered with inponderables.