Question on Powders

[Socalman]

Do manufacturers make changes in their powders without changing the name or numbers?

I have not reloaded in a few years now and if I pick up a powder like IMR 4895 or Titegroup or any others I used in the past, can I still rely on my older manuals that were current at the time or will the manufacturers have made changes that require looking at the new manuals?

[highpower790]

Older books with powder that has been around forever will not be a issue.Lot to lot variations in powder do exist so proceed accordingly when working with multiple lots.Usually +/- 1/2gr can be expected.

[J-cat]

It depends on the powder. 25 year old Reloader 7 completely different from current. Made in a different country with completely different kernel size and shape, for example. I read on the internet the new stuff has more nitroglycerin in it.

It’s best to consult most recent manufacturer data. It’s right there on their website.

[Fjold]

Powder manufacturers make powders in lots. They blend powder to meet certain specifications but lots will vary slightly. You will see some velocity and accuracy differences between lots if you and your gun are good enough to see small variations.

As long as you're not loading at or above max, it shouldn't be dangerous.

[Dave626]

Summer time the velocity will jump. if you load near Max at winter time, back it up in summer time.

[ar15barrels]

Do manufacturers make changes in their powders without changing the name or numbers?

I have not reloaded in a few years now and if I pick up a powder like IMR 4895 or Titegroup or any others I used in the past, can I still rely on my older manuals that were current at the time or will the manufacturers have made changes that require looking at the new manuals?

The powders you can typically buy for reloading are called "cannister grade" powders.
What this means is that the powder maker has a performance standard that they specifiy the powder to work to.
This is important so that you can use reloading data developed at different times/lots and still be safe in the future.
Powder companies may change their powder sources, formulas or blends, but the new lots are manufactured to perform as similarly to the old lots as possible so that the old reloading data can be used.
There will be variations between lots and that's why the standard warnings all apply when switching between lots.
If you are pushing the limits, back down with a new lot and re-develop your load.
If you are running moderate loads, you may not even need to change your load at all.

[smoothy8500]

Over the twenty-some-odd years, IMR and Winchester powders have been very consistent.

[Sailormilan2]

It's my understanding, and I could have it wrong, that cannister grade powders are blended to be within 3% of a standard.

[buffybuster]

Any powder in retail packaging is canister grade.

[Socalman]

Thank you all for the answers. Pretty much they were what I suspected. A wise man once told me that when you open a new can of powder, back off a bit on the load so that is what I figured I would do.