Tried some (older) 7828 my dad-in-law had available. Got good accuracy with my .280 Rem 160-grainers, 100 fps more with my .300 H&H 220-grainers, then with the .270 Wby a surprise. (The can is getting down to the last inch or so.)

Top Nosler manual loading [73 grains IMR 7828 with 160-grain Partitions that shoot well enough with H4831SC, but thought I'd try anyway]. Too Hot!!!! Primer starting to crater and ejection marks on the "lettering" of the brass. Primer pockets are still okay, but at 3200 fps something is different. I've had the same thing happen at the bottom of an older can of IMR 4831. Guess the powder has started turning to dust instead of granules. Anyway, there are a couple older threads about this combo and thought I'd post . Comments?

Is the .270 Weatherby a factory (free bored) chamber? Lots of custom .270 WBY chambers are made with a more conventional leade, thus they generate more pressure with less powder than a spec Weatherby chamber with its very long throat.

There you are. Re-barreled by Hill Country Rifles to same specs as the factory barrel we shot out ( third or fourth owner). Speeds with the 7831's stack up with loads from up to ten available manuals. (2800 fps with H and 2950 with IMR without pressure signs.)

Might try again with fresh IMR 7828SSC (but it was going so well...)

I think this just goes to show that every gun and every powder lot is a law upon itself. I general, I find the Nosler manuals more on the "optimistic" side, and it is rare that I seriously manage to approach the velocities they publish. On the rare occasions where I do approach (note: approach, not match!) Nosler published velocities, I have to admit doing so by leaning on the loads. And if I would strictly adhere to my own general principles of safety in handloading, I should probably back off a grain or two...

I have also loaded the .270 Wby with IMR 7828. It is supposedly one of THE powders for that caliber. I found decent accuracy about 2 grs below book max (if memory serves I load 74 grs - vs. 76 max - with a 130 grs TSX) but I got nowhere the velocity I had hoped for (~3200 fps observed vs. ~3400-~3500 hoped for). Why?? Beats me, perhaps the chamber or bore of that gun is on the larger side, who knows?? Adding the extra 2 grs up to book max would not have brought me the "missing" 2-300 fps. As accuracy was good, I settled for the lower velocity - which had the added advantage that trajectory was the same as my .300 Win Mag 168 grs TSX load, and I could therefore use the same Leupold with a custom ballistic compensation reticle.

Just in case you don't find any joy with the .270 Wby/IMR 7828 combination, a friend of mine has had very good results using RL25 in that cartridge. Sadly, I can't source that powder where I live...

- mike

mho

I exceeded the manual value by 100 fps with the OLD 7828.
Again, I am asking if anyone has experienced different results as they worked towards the very last of a lot of powder.
My contention / opinion is that the powder's deterioration is coming into play. There's not the usual smell of solvent to it that I have with most if not all my other powders.

Barry

I have never seen a load get hotter toward the bottom of the can but if its old enough I could see a problem. As for Nosler being optimistic, My loads in a 7mmWby are one step below max and just as fast as max. Good for case life and trajectory. I took it to max but just below was very accurate.

Thanks to all. 24hourcampfire response says my manual data has been revised (way down).