Using A Different Lot# of Powder

[vkoczara]

I reload the .223 for varmint shooting, I load for volume 500 hundred - 1000 at a time, my loads are tuned perfect and I'm down to my last 200 rounds, I have no more powder of the same lot # or components, how different will a new lot # of powder change my group size if i make the loads the same as i have the last time?
Or do i have to go through the load developing process again as well as re-zero for the new batch of loads?

Thanks

 

[Travelor]

It depends - don't you just hate an answer like that. Some times new lost shoot just as good or better than other lots. It also depends on which powder you are loading. Some powders, like VARGET, tend to vary more than others.

My suggestion is load about 10 rounds with the new lot and take them to the range and chrono them and shoot for groups against the existing loads with the old lot.

You may have to adjust the load just a small amount to get the same results. Wish I had a better answer for you.

George

 

[fdshuster]

Agree with Travelor. When opening a new can with a different lot#, will load a maximum of 20 rds., and compare results with results from rounds loaded identically with the previous lot#, same rifle, of course. If no outstanding/ noticable changes will continue "business as usual". Over the years cannot remember any changes.

 

[Chuckhunter]

VinMan, Travelor, gave you the best advice. This is a prime example why one should own a chronograph. They can save you hours of frustration and get you back to where you want to be with a minimal amount time and components expended. Once you have the chrono data for your pet load recorded, the new lot of powder can be adjusted, either up or down to duplicate your original load, (this isn't always necessary but usually is). I would do as travelor suggested and make up ten rounds with your original load and if you see no difference on the target, stay put. If however your load doesn't shoot the same, or close to the same, you might have to make an adjustment, either up or down . If you have a chrono, no problem, if you don,t, perhaps a friend has one and will lend you a hand. Good Luck.

 

[ShooterB]

Good advice so far. The only thing I might add is that if your current load is at or near max, drop your powder charge down a llittle and work back up, checking for pressure signs.

 

[kitsap]

One addition when comparing, it is good to have 5 to 10 rounds of the old batch of ammunition reloaded with the old powder available to shoot at the same range session as the new. This gives you a comparison under as near the same conditions as possible.

DougF