I am using VV N565 Powder in my 7mm Rem Mag for a maximum load with 155gr bullets. Since I am out of my powder I ordered more and I am assuming that the new powder will be from a different lot...my question is SHOULD my loads with the new powder be pretty much the same as the ones I have loaded now??

A very knowledgeable reloader friend told me that different lot's can vary as much as 5-10% which seems pretty high...is this true??

Just wondering what your experiences and opinions are... THANKS!

Yes no and maybe.

Clear as mud I know

Reduce the charge work up to the original one you are using

It could be that different. If your load is out on the ragged edge, I would do a minor work up. Drop a few grains, see if the velocity is where you want it, and then go back up a grain at a time until you match velocity or some pressure signs show up would be my method with it.

I suspect not. VV powders seem to be pretty consistent across lots, at least I have no issues with my IPSC loads that use it- I burn a lot of their stuff in handguns, mainly due to its consistency.

Thanks for the reply's fellas!

Yes, before I load up a bunch, I am going to chrono a few and see (and hope) that the velocity matches or is at least very close.

I too was told that the VV powders, and especially the temp stable N565 powder that I am using is very stable so hopefully I will be ok.

I don't load much AR2209 ( H4350 ) but it frequently features as a possible in my loads development when comparing different powders. So for some years I slowly used one lot of AR2209 until it ran out. Likely it was used over more than a 25 year timespan. Eventually I bought a new 1 lb. container and soon found the same weight charges were chronographing around 100 fps faster, in .300 WM IIRC. This is the only powder with which I noticed this happening but might have happened to a lesser degree with others.
These days when I find a good load with a certain powder I try to buy several pounds of the same manufactured lot so I can keep loading the same charge without worrying.
But in saying that I currently use two different lots of RL26 which over the Chronograph seem identical in velocity and POI.

Similar to 30.06king's experience with AR2209, a trader on our national auction site posted a can of AR2213 (H4831) for sale which he said was considerably faster burning than previous lots from which he had developed loads from. He did not wish to use the new lot of powder.
I was surprised to read this at the time as I have used various AR (Hodgdon) powders without any issues. I thought maybe the trader had made an error when setting his powder measure or weighing charges to get such a discrepancy but maybe at times these powders do vary more than just a few points of grains from lot to lot.

if you were not using MAX loads it shouldn't make any difference, I never change my loads from lot to lot, same point of impact.. but that's me, the smaller the cartage the more it changes, like 223 rem.

quote:

Originally posted by vines:
if you were not using MAX loads it shouldn't make any difference, I never change my loads from lot to lot, same point of impact.. but that's me, the smaller the cartage the more it changes, like 223 rem.

I agree. If my loads weren't max I wouldn't worry about it. It's a 7mmRM 155gr at 3,260 so it's hot but no heavy bolt lift, etc

I used to drive my cars about as fast as I dared.
And loaded my rifles to the max too.

Took quite awhile and bunch of tickets to learn
there's no future in going to the max in cars
or reloading ammo either.

You won't ever see a difference enough on game
shot at 3000fps compared to 3250fps.

So why load to the max? You're just putting
that much more strain on your components and
firearms. Plus you're using that much more
powder too.

I've decided on a velocity I'd like to reach and
shoot, then load to it even when it's easy to
exceed that by quite a bit.
For hunting use I like 3000fps in most, IF it's
practical. Small cal varmint shooting depends
on a logical velocity. Real small cases are
critical so drop a few tenths or half grain.
Big bores a couple grains less will do the
same job easier.
Same as driving 80 instead of 90 or more in a
75mph zone. Less gas, much less worry and wear
on equipment.

Just some thoughts I've gone thru over the years.

George

Much wisdom there from George; I find that young guys want to go the fastest and hottest at everything; only to later realize that it accomplishes nothing and is often counterproductive. (Meaning expensive)
Now, back to powder: making smokeless propellant is an art; when they make a batch of it, they do not know if it will be the same as all previous batches or not; often it isn't. So, in loading in a factory, they just change the amount and move on. But for "Canister" powders, sold to reloaders, each lot of IMR0099 must be exactly the same as it was in 1935; in order for two things to happen; all those reloading manuals out there to be valid, and for hand loaders to rely on them and not get into too much trouble.
So, they Blend lots together to get the desired, standardized, burn rate.
Yes, there have been exceptions. But the system, overall, works well. And Vita Vhouri is very consistent.
Slow down.

One of my jobs was managing Tank Ammunition for AMCCOM, now JMC. The propellant I bought (from Radford) was M30, and they carefully blended it so as to get the exact velocity and pressure as every other lot. Each cartridge uses 16 pounds of it. That is especially important when you are trying to hit a T72 at 2000 Meters. And your life depends on doing so.
Not that we are trying to do that; that was a random example.

quote:

And Vita Vhouri is very consistent.

Probably true but the reason I personally don't use this brand is I found heavy carbon fouling with the variants I did try. Can't remember which variants as it was some years ago. Found the same sort of fouling with Superformance when I tried that.
Any comments on levels of carbon fouling with Vihtavuori powders these days...???

??????????????????maybe, but I've managed to ignore it over the years..