How safe is old loading data?

For the last 15 years my shooting has been confined to the range rather than the field. Recently I was asked to help in culling a small mob of goats for a friend. The terrain is fairly open where shooting ranges will be around 100 meters at least and the only suitable rifle I have for the task right now is my .243 Win, so I dug out some hand loads from the back of my ammo cupboard.

The label on the boxes show these were loaded in 1998 and 37 grains of ADI AR 2208 powder was loaded under a 100 grain Hornaby BTSP projectile.

This morning I took my small ring Mauser action .243 to the range to check the sighting. As the 100 meter range is undergoing some construction I was reduced to shooting at 50 meters. As I was setting up I thought I should check a ballistics chart to see where point of impact should be at 50 meters for a 180 meter zero. First I went to the ADI on-line loading chart to get the velocity on my smartphone before running the ballistics app.

I was shocked to see that the maximum powder charge of AR 2208 in the .243 is now listed at only 33.7 grains.

Despite having shot at least 50 of these hand loads through this rifle when they were first loaded, with no issues, I decided not to shoot and to go home and check my loading reference books. In the 1998 era ADI Reloading Handbook I used at the time 37 grains of AR 2208 is listed as the maximum but still safe load in this calibre. Furthermore the handbook stated the power is similar in burning rate to IMR 4064 and my loading handbook from the same era lists 37.5 grains of this powder as a maximum load.

I realise that powder manufacturers will make small changes to powders over the years which will possibly result in altering loading data. I also realise that the maximum loads may have been reduced for safety reasons at some time. My question is:

Would it be considered safe to continue shooting these loads, put together with data from when this batch of powder was manufactured, or would it be wiser to dump them and start again?

I have tried to extract the powder this afternoon using a bullet puller, but out of the 5 cartridges I have tried 3 took more than 150 hits against a 50mm block of wood held on a concrete surface to separate and the remaining two and hardly moved after more than 200 hits. If these loads are unsafe I will end up dumping the remaining 55 or so and getting new cases, an unexpected cost!

Any advice would be welcome.

Put them in your seating die and seat them maybe 20 thou/0.5mm deeper. This will break the seal that forms with age. You should then be able to strip them with your inertia puller.

Just a thought, if your loads are from 1998 your powder will be equivalent to data from that time also, so, in my humble opinion, i think it is safe to shoot.
Remember, some us still shooting surplus ammo from "many" years ago.

Thank you for your time, hope it help.

Mac

My pet load for 243 uses 37gr of 2208
As the possibility of law suits increased, over the years, powder manufacturers built in a 'safety margin'
Nick Harvey's original manual, compared to latter ones, makes interesting reading.

They still claim 2208 is an "equivalent" for 4064. Recalling comments from similar threads reducing loads could be the fear of US litigation. Looking in my hogdon manual they now list 36.5 gr for 4064 and a 100gr, and the oldest book I have (Lyman 1964) lists 39gr of 4064 as max for the 100 grain.
I came across some 308 I'd loaded nearly 18 years ago last year 186gr lapua miras over 43gr of 4064 they shot fine back then and still shot ok when I burned them off to reclaim the cases. Looking in the modern books they are a "bit too hot" but Duponts suggested max was 45 back then.
They were "safe" when you loaded so if they've been stored well I cant think of any reason not to use them.

If they were safe in your rifle when loaded I dont see why that would change.
Perhaps work up again if you have new powder to reload tho batches can vary.

Shoot them and don't worry. Your 1998 data is for your 1998 powder.
When you come to load some more ammo up, work up as if for a new load.