I want to throw this question out to everyone. Have any of you noticed any significant differences in velocity and pressure from lot to lot with Reloder 15? I have not really noticed this but I have to confess, I will usually chronograph a load the first time and then I don't usually "re-chronograph" it again with each new lot of powder. The reason I ask is because large lot to lot variations with Reloder 15 seems to be common knowledge on the Double Rifle thread and there is one particular thread that I started with respect to the proper weight of a .500 NE where DirkLawyer and MJines are reporting a NINE GRAIN DIFFERENCE IN LOADS TO GET SIMILAR VELOCITIES! That's a huge difference.

I use a lot of Reloder 15 but I am not going use it up and go another direction if there is indeed such big lot to lot variations.

From what I`ve heard there can be as much as a +/-5% variation in burn rate in canister powder and it still be in tolerance. That is supposedly the reasoning behind the warning to start with a 10% reduction in max loads.
You might never see that much change, but in the end it all comes down to the luck of the draw.

RL-15 is noted for being very consistant lot to lot, however I think I read where they recently changed it. I have not shot any of the latest but the kernels are defiintely darker and glossier than all of my previous lots of RL-15. I just may load some up and see what gives.

Be aware that load densities varying 9 grains would be consistant with Reloader powders that were manufactured under Hercules manufacture (marked made in USA) and Alliant manufacture (marked made in Sweden). They are different animals and take different charges. The USA powder is older and mostly shot up except for those who 'hoarded; it when the company changed hands in the mid 80's.

quote:

Originally posted by buckeyeshooter:
Be aware that load densities varying 9 grains would be consistant with Reloader powders that were manufactured under Hercules manufacture (marked made in USA) and Alliant manufacture (marked made in Sweden). They are different animals and take different charges. The USA powder is older and mostly shot up except for those who 'hoarded; it when the company changed hands in the mid 80's.

I knew there was a reason I never used RL-15 until last year!

quote:

Originally posted by buckeyeshooter:
Be aware that load densities varying 9 grains would be consistant with Reloader powders that were manufactured under Hercules manufacture (marked made in USA) and Alliant manufacture (marked made in Sweden). They are different animals and take different charges. The USA powder is older and mostly shot up except for those who 'hoarded; it when the company changed hands in the mid 80's.

Buckeyeshooter:

Are you sure this information is correct? I have a one pound container of Reloder 15 that says "Made in Sweden for Alliant powder". It is lot 75109 and on the container is says it was made on Oct. 8, 2007. I also have a five pounder of Reloder 15 "Made with pride in the USA" and it clearly says on the back label that it was made on Dec. 14, 2007. The lot number is 75138. I have other containers of Alliant powder that say they were made in Sweden. The dates and lot numbers of the Reloder 15 seem consistent although the labels would suggest different points of manufacture.

I've got some Swedish made RL-15, two different lots, one made Feb 6 2009 and the other Feb 14 2009.

Wow, you learn something new every day around here!

My current container of RL-15 is Made in Sweden for Alliant Powder

CE0519 Aug 29, 2008 Shift 2 Lot 85094

For the record I went out and shot some today but didn't Chrony. Same point of impact as my other lot. Gee, I wish that I had kept that other container. It was a bit different than this one.

I'm intrigued by this thread, so I went out to the powder storage cupboard and dug out the five one pound containers of RL-15 I have.
One bottle has no markings about lot number, or date of Mfgr. On the bottom front of the lable it says, "Made in Sewden for New River Energetics".??? This is a mystery.
Then, there are two plastic bottles that have Manufactured Nov,24. 2008, Lot Number 85109. At the bottom of the lables in front is says, "Made in Sweden For Alliant Powder". I'm OK with this.
Now, here's a real question driver. The remaining two one pound bottles have the same markings. Each says: Mfgr May 7, 2008, with Lot Numbers 75138. Again, on the bottom front of the lable it says; "Made In Sweden For Alliant Powder".
That's the same Lot Number that Dave Bush mentioned he had in a 5 pound container that was made in the US!??? I suspect the labels don't match the places of Mfgr. I can see no other answer.
A side note. I have two different rifles that shoot an OLD lot of RL-15 very well. One is a 250 Savage AI, and I loaded out that old Lot a few weeks ago for the 250 Sav AI, and threw the old container away. The container was one of the old ones that had the small opening with a red threaded cap, and IIRC, the bottle was made of cardboard. Anyway, I was out shooting that old lot yeasterday. The load is, 41.5 grains of powder and Hornady's 75 grain bullets. The reason I was shooting it was I was zeroing a hunting scope on the rifle. Previous shooting was done with a 20x scope I use for load developing, and I'm fixing on going hunting soon with that rifle. As with the 20x scope, it shot very good for me; 3 shots into a .600 group at 100 yards. With the 20x scope, I shot 3 shots into a 3/8" group, same distance.
At the same time I loaded out that old lot of powder, I opened a new plastic bottle which happened to be the unmarked one I mention above, and loaded up half of that bottle. Now, I will take some of these loads out and shoot them to see if they equal that earlier stuff that shot so well.
I have not opened or used any of the Lot Number 75138 as I just bought that at my local store, after doing the loading I just mentioned above.
The plot thickens..

Don

quote:

Originally posted by Dave Bush:
... Have any of you noticed any significant differences in velocity and pressure from lot to lot with Reloder 15? ...

Hey Dave, I realize you are focused on RL-15, however I'd suggest the Powder "of any type or manufacturer" has some Variance in it. The real problem is we all use different Methods to determine if the actual Lot-to-Lot change is significant. Some of the Methods are questionalbe at best and dangerous at worst. The RL-22 fiasco comes to mind, and other Powders have been discontinued due to erratic behavior in specific cartridges - like H450(one of my old favorites). Just loading the new jug of RL-22(depending on the one you started with) could lock-up the Bolt. Fortunately the variance is normally not nearly that significant.

Sooooo, there is a reason ALL Reloading Manuals recommend that a person should Redevelop a Load any time a component is changed, they do it to keep reloaders erring on the Safe side.

Don:

My chronograph went down. I will order a new one this week and test to see if there is any velocity diffference between the stuff I have that says it was made in Sweden and the stuff with the USA label.

I took a bit out of each canister last night and at least to the naked eye, it appears to be the same.

Absolutely positive. The Hercules Reloder powders were rolled into Alliant in the late 80's. I have both Reloader 15 and Reloader 7 that are marked made in USA. The USA marked powders take 5 to 7 grains MORE powder for the same velocity. If I remember correctly there was also an Alliant plant change somewhere along the line. Just goes to show you, lots can vary a bunch. Be careful, work up loads carefully and buy large quantities of the same lot of powder when it is possible.

Buckeyeshooter:

Of course, what you say is indeed possible but I am skeptical that the powder I have is 17-20 years old!!?? It's in a new plastic container and it is clearly marked as being manufactured in 2007 from a recent lot. I will test it to see if the same loads produce less velocity.

Not saying it is old. But I do know there were 3 production points. The hercules plant burned down, so it is not made there anymore. Then there were a couple alliant plants. I have heard, but am not certain that one plant also made Viti Vihuri powders also. I can tell you for a fact, that the USA made hercules powders have colored rods in them that the newer powders do not have. In Reloader 7 they are red. If I correctly remember in Reloader 15 they are green.

Some people are so obsessed with accuracy as to check the density of every jug of powder they buy. I happen to be one of those nuts. After doing that for more years than I like to think about, I decided not to use Alliant Red Dot, Green Dot, RL 12, RL 15, Unique, nor RL 22. All these powders were more than 5% different in density from lot to lot. I have not measured any Alliant powder density in the last 5 years, so things may have changed.

The only other powder I tried that was unacceptably variable in density was Varget, and again that was over 5 years ago.

All other Hodgon powders I have used, and all Winchester, IMR, and Vihtavuori have varied less than 5% from lot to lot, so far.

Checking density is very easy if you have a scale that can weigh in grams and a measure that is calibrated in cubic centimeters. Lee's dippers are handy, since they are cc. measure. Lee's manual also describes the best way to get a repeatable level load in a dipper. Then you just divide the weight in grams by the volume in cc. and you get a percentage of density as compared to the standard--water--which is 1 (one) slap a label on that jug and you're done until the next powder purchase. Most powders are less than 1 (my current jug of N-135 is 93%, for example) but some can be denser than water. Ball, or spherical powders like W760 or H335 may actually give you results of 100% or more. It is a good idea to measure and calculate several times and take an average density, especially when using flake and long grained powders.

great tip!

I will agree that RL-15 density varies lot to lot, But and this is a big But, the same charges always appear to be the same. To be clear 24.5 gns may fill the case more or less than the lot before, but point of impact does not change.

ETA: To be clearer, I often have to set my powder measure to a different setting on different lots of RL-15 to get 24.5 gns, but 24.5 gns performs the same between lots. The change in the setting is not a small one either.

This variation may well be why the old (very old) Speer manual listed 49 grains of Re15 as max with a 150 bullet and now no one I can think of lists more than 46.