I'm afraid to pull the trigger now.

[zaphar]

Does anybody have a good picture of a flat primer?

Yes, go to this website and towards the bottom of the page: http://38super.net/Pages/Factory2.html there are several examples.

 

[ArchAngelCD]

First off thanks to all for your help.
I shot today and feel I did well for my first attempt.
With the .300WinMag, I started with 52gr of IMR4064 pushing a hornady interlock 165BTSP and increased by .5 per 5 shot group. I didn't see a massive change in accuracy but the best groups were from 53-54.5. I stopped as things stated to open back up at 55.5. No signs of pressure. Best groups if you take out a pulled shot here and there were at or less than MOA, .708" being the best one.
Now the 7mm-08 was a bit different. Starting with 44gr of IMR4350 with half grain steps groups were not so good, +2" on average with the worst around 4". I did get one at 1.46" at 46gr. Good enough to shoot a deer here but I think it should do better. I did see some primer flattening I think on the hotter loads.
It was about 25 degrees when I started and got to about 35. Shooting off a crappy big game folding bench rest that wobbles all over.

Where did you say you are getting your load data? IMO you have those powders reversed, you should be using the slower powder in the 300 Win Mag. Don't get me wrong, nothing wrong with using IMR4350 in the 7mm-08 but why IMR4064 in the 300 Win Mag? If anything I would be using IMR4350 in both or better yet, 4831 in the 300 Win Mag.

Also, why do you think your 7mm-08 load is compressed?

 

[The Taxidermist]

Speer and hornady manuals. They have lots of powders to choose from. Unfortunately there's no way to know which one to start with.
The powder came nearly to the top of the neck and you could hear it crunching as you seat the bullet.

 

[The Taxidermist]

I may load the .300 back up with the 4350 and try again. Speer doesn't have the 4064 listed for 7-08 but I know the gun likes fusion 120gr rounds so 145 may be too much out of a 1:9.5", 18" barrel

 

[jwrowland77]

Go here and check and see. http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

This is a great calculator.

 

[The Taxidermist]

I was also surprised to see the 165s hit within an inch, inch and a half if where the 220 grn bullets I've been shooting are.

 

[ironworkerwill]

7mm-08

I have had good luck with Rl 17 140gr+ and H380 and Varget 140grn and lighter. If you want that light barrel to show out use 130 smk with H380 at around 45 grns. Another is 139 hdy sp with 42+ gns of Varget{max is 43.5 but at 43 grains it opened up}. I would not shoot any thing larger than 145 grn bullets or more than 1.165'' long in a 1:9.5 but that weight should be good.