same powder / different batch


November 8, 2008, 12:01 AM
how many of you guys reduce, and re-work up your favorite loads (the ones that are NOT at or above max published data) when you switch from one bottle/batch of powder to another of the same brand & type? personally, i do not. do you really think there is that much difference between batches?

If you enjoyed reading about "same powder / different batch" here in archive, you'll LOVE our community. Come join today for the full version!
November 8, 2008, 12:21 AM
With the powders I mostly use, I find there's is very little or nil variations between batches.
But then again I don't like running right on max loadings either. As I like my brass to last 'N' last. ;)

November 8, 2008, 12:32 AM
If a powder 'batch' is the same as a different powder 'lot', to you, you should work up the load again. 'Lots' can have slightly different burn rates. However, it really only matters in benchrest shooting. Doesn't make a lot of difference for hunting loads. Mind you, if you're above published max loads, you're already playing with disaster.

November 8, 2008, 12:37 AM
with mid loadings for revolvers no .

with top end hi pressure loads yes even if i change lot# of primer, brass or jacketed bullets wich i rarely load these days yes.


The Bushmaster
November 8, 2008, 12:38 AM
In the past there was a lot of difference from lot to lot. Now days there is little difference from lot to lot. I have some Hercules 2400 that is from the '60s that is just 25 fps slower (old age) then todays Alliant 2400.

Component change (bullet, primer and maybe the case) is a different story...

November 8, 2008, 06:32 AM
One of my best loads is right at the max. On that one I back off and come back up. But I only load one rounds of each step to check for pressure.

November 8, 2008, 09:31 AM
As has been posted, if you are running around max, double check things. I always check to see if a new lot throws the same weight for a given setting on my 10X etc, because I log settings and just dial my load back in when I'm ready. That does not take into account burn rate, which still has to be checked by working up the load again, but as I said, I only do that if it is at or near max.

Ol` Joe
November 8, 2008, 10:31 AM
I always drop a couple grains and rechrono the load to compare to what I got with the older lot. If they are the same or very close (taking temp into consideration) I load at the old level, if not I rework the load.
There isn`t much difference most times, but sometimes they do vary more then one would like to think.

November 8, 2008, 10:43 AM
.....since I feel no need to load to max(I just grab a bigger gun), and since most major manufacturers strive to keep their powder as consistent as possible, I load every bottle the same. Also, because I go thru powder quite quickly and generally have another jug on hand, when it will fit, I'll mix the remainder of the old jug with the contents of the new jug to help the consistency. I use my guns primarily for hunting and target shooting, and no competition.......this works well enough for my applications.....

November 9, 2008, 07:04 PM
Guns are like Harleys and can never have too many. yeah, and we love to fondle them!

November 9, 2008, 08:05 PM
ok, there is no -im new an haven't used a lb of powder yet- choice lol. id say it wouldnt hurt to run a few loads over the ol' chrony an check up on things anyhow

November 10, 2008, 09:07 AM
One of my best loads is right at the max. On that one I back off and come back up. But I only load one rounds of each step to check for pressure.

Since I am relatively new to reloading, I have read about the signs of too much pressure. But how does one actually check the pressure?

November 10, 2008, 01:08 PM
Since I am relatively new to reloading, I have read about the signs of too much pressure. But how does one actually check the pressure?


The best way is a combination of running the ammo over a chrony and reading pressure signs on your brass. The reason for this is, pressure and velocity go hand-in-hand, and excessive pressure has an effect on the relatively soft brass case. First, you should have a reasonable idea as to what velocity to expect from your rifle with the load you are using. For example, with a long barrelled bolt action .308Win with 175gr bullets and a suitable powder, you may be able to reach 2750fps, but anything more than that is unreasonable. If at any time your chrony readings exceeds what is to be expected from a particular load fired in a particular platform, stop right there. Next, you examine your brass after firing. The first sign is flattened primers. Nothing particularly wrong with that, just that is the first sign of normal to slightly high pressure. The second sign is cratered firing pin dimples on your primer, although this condition can also be caused by an enlarged firing pin hole in your boltface. The third sign is the one that says "Whow, back off", and that is a shiny spot on the base of the case. This is caused by the brass "flowing" back into the ejector hole. The fourth sign is hard bolt lift, and this one says "What, you didn't see the third sign?". While there are other ways, this is the way that is commonly used. Hope that helps.


November 10, 2008, 04:55 PM
Thanks, Don!

A few weeks ago I had posted a question about whether chronographs are necessary. MidwayUSA had some good deals at the time, but the prevailing consensus was no, they are toys.

I am not trying to load to the max, but If I am going to try to be detailed and precise in my reloading, I think it would be worth the hundred or so dollars to get a chronograph.

Thanks again for your feedback. Now I know what to ask for for the holiday/birthday season.


dagger dog
November 10, 2008, 05:16 PM
I tend to shoot mild loads, so the possibility of a different "batch,run" of powder causing saftey problems is a lot less .

The primer, case capacity swaps are the ones you really want to rework a load with!

The Bushmaster
November 10, 2008, 05:29 PM
edSky...Who told you they were toys. They are not necessary, but quite handy when working up a load. Every new load and every change I make runs across my chronograph to insure that I didn't do something stupid...

Friendly, Don't Fire!
November 10, 2008, 05:51 PM
First, let me say chronographs are an extremely useful tool that I didn't ever think I would need, and then I bought one (a Shooting Chrony F1 from MidwayUSA) and was amazed how far off I was at estimating the speed of the bullets I was reloading (using the manual's estimated bullet speeds).

When you are off by several hundred feet per second, that can mean several tenths of an inch in vertical variance when sighting in the scope at 100 yards, double that variance at 200, triple that variance at 300 and quadruple the variance at 400. Of course, at 500 yards, you are five times off! Three tenths of an inch off at 100 yards would make it 15 tenths (or 1 1/2" off-vertically) at 500 yards! Now figure that your scope is probably set wrong (mine was) at 100 yards and having the trajectory written out to 500 yards was all wrong, the further the distance, the more "WRONG" the written-out trajectory was (I have it written in ink on the left side of my brown rubber buttplate)!

That is why, in the past, I couldn't hit the woodchucks past about 250 yards. I was shooting way too high, thinking the bullet was going slower than it was and the trajectory not as flat as it really is!

Without the chronograph, I thought my bullets were traveling around 3,700 FPS. With the chronograph, the bullets are averaging 4,000 FPS! Realizing just how flat my 22-250 is shooting with 50g Speer bullets, I was able to hit a woodchuck this summer at 500 yards!

As for the question about working up loads after changing lots of powder, no I never did, nor did I ever notice a difference in pressure signs when looking at the primers (the hottest load I have in any of my guns is that 22-250 load which the gun loves at that maximum load). Most of my loads are middle-of-the-road as that is typically where I find the accuracy.

Since I only shoot when I'm serious about hitting something and I don't plink at all with that gun, I'm not afraid of wearing out the barrel in my lifetime.

November 10, 2008, 07:35 PM
Like posted earlier its more important when you are close or over the posted loads. I ALWAYS start over on max loads but never on my light plinking loads. I was loading 110 grain 357's with H110 at max and ran out of powder, grabbed another bottle and kept loading and they turned out so hot that the primers flowed so bad that you could not tell primer from brass case. I was using the brass colored winchesters at the time. I also had to use a drift punch to remove the case from the cylinder.

Larry E
November 11, 2008, 07:14 PM
As someone else said YES and NO. With light handgun loads it usually won't make a difference, but in max loads there CAN be enough of a difference to get a person into trouble. I had a load with an early lot of Benchmark that shot like a house afire and gave great velocities in a .223 varmint rifle. A new lot that I'd fortunately started off with a lighter charge gave excessive pressures with the starting load, and I tend to load my varmint rifles fairly hot.

If you don't mind rifles or handguns coming undone right up next to your head or in your hands you can do whatever you'd like. :uhoh:

If you enjoyed reading about "same powder / different batch" here in archive, you'll LOVE our community. Come join today for the full version!