Gentlemen,
I have started to load for a brother's Rem in 7-08, and I started with IMR 4895. The load is this:
Wincester case-- brand new
Wincester WLR primer
Hornady 139 gr. SP
IMR 4895 Started at 39.0 and working to 43.5 possibly.
Primers were flattening with the first shot. What is going on?
Regards,
Graham

flattening with 39.0grains in it?

How flat? Is the primer dent sharp edged or curved?

Any chance of a pic?

Flat primers are NOT always a high pressure sign.
New brass is almost always under size or close to minum specks.
Was the bolt lift hard?
Are there extractor marks in the face of the rim?
Do the case s have a buldge at the base?
Did you measure the case for expansion at the base ?
The fire formed cases will perform diffrently.
More volume.
what you are experiencing may be low pressure signs.
use a fireformed case and increase the load a 1/2 grain and check for changes.especially bolt lift. if it hard then you are at the max for that comination.

Gentlemen,
The boltlift was normal(very easy in that rifle). The primer was still rounded, just pressed against the bolt face a bit. I hadn't considered the low pressure aspect of the spectrum yet.
Regards, Graham

Each rifle is different but I would shocked if you have pressure problems. I have used 44.0gr of IMR4895 w/ Hornady 139gr SP,SST and IB in 2 different rifles in the GA and LA summer heat. I don't have any pressure signs at all. Sometimes though, some powder/bullet/rifle recipes just don't work. My worst has been the 7mm-08 with IMR4895 and the 140gr TSX. You may have found one that just doesn't work...

RH

when the primer face is flat all the way across to the edges, and the edge is a sharp and defined that is getting to a sign of highish pressure, i get it with factory loads sometimes. its more of a concern when the primer flowing around the pin and is "cratering"

If the primer wasn't seated deeply enough and protrudes below the primer pocket ever so slightly, it will flatten regardless of the powder charge when fired. Since it was a new case, it may have been min dimensions and not therefore, not fired on bolt closing.

did you full length resize your new brass to far down and create excessive head space,that would let the brass expand back to slam the primer against your bolt face.try patial neck resizeing with your fl die,or use a .10 thousants shim of metal or paper with a hole in the middle so your decapping pin can pass through,each gun is different because of how the chamber was cut,al resized brass should be snug but not tight,708 is a fine round indeed loaded quite a bit of it my self for a good friend,regards and keep us posted

I will indeed keep ya'll posted. I have been away for a few days for work, but I will probably get some more information later this week. I will post as soon as I know more. I am loading this for my little brother's gun, and told him to test the loads as best he could and save all the targets for me to inspect. I haven't spoken to him for a couple of days, so I will know more by the end of the weekend.
Thanks again,
Graham