I've used Retumbo and 200 gr. bullets and got 1 1/2" groups...

I changed to IMR 7828 and started with the lowest load in the Nosler book with 80.5grs and 180BT's then loaded 81.5grs. The last load (81.5grs) were very accurate but seemed to flatten the primers more , actually pretty flat.

I checked Hodgdons website and they show IMR 7828 max. 80.5 grs. Other books and data I've read show about 84grs. or so max.. Has the IMR 7828 changed recently???

Also, how many times can the 300W cases be reloaded normally.

Also should I try H1000?
Thanks!

I'm still working for the "perfect load" for my .300 Wby Vanguard, but I've found some promising loads with:
178 gr AMax bullets and H1000
180 gr TSX bullets and RL-22, H1000, Imr 7828
168 gr TSX bullets and IMR 4350
168 gr Hornady BTHP bullets and RL-22

This is a hunting rifle, and my goal is sub-MOA 3 shot groups at 3350+ fps for the 168 gr bullets and 3200+ fps for the 178/180 gr bullets, AND tight primer pockets.

Yes, I like the tight primer pockets!

I'm going to start over with some new brass and chrono the 81.5 IMR 7828 load when I get a chance. Then work up from there using the nosler data. I want to shoot either 180 or 200 Noslers.

I'm also going to chrono some factory loads and see how they do.

Apparantly the difference in powder charge data is because Hodgdon's is using a speer bullet that has more bearing surface thus more pressure.

I got 5 reloads out of mine before the brass started to get thin near the belt.

Thanks Leo..

In my 300 Weatherby -- a Remington 700 -- I get best velocity from IMR 7828. I can get 3200+ f.p.s. with 180 gr. bullets and 3000+ f.p.s. with 200 grain ones. That's from a 24 inch barrel, and without unduly flattening the primers. I usually use Remington brass and Federal 215 primers.

Your 81.5 gr of IMR 7828 with a 200 grain bullet is well below my top load, but may be too much for your rifle.

I got the best accuracy from the Nosler 200 grain Accubond bullet.

I found that RL22 may give somewhat better accuracy in my rifle, but with some velocity sacrifice, maybe about 100 f.p.s.

That's good info, thx.

I think I've made a major mistake with reloading the IMR powder.

The loads with Retumbo were with once fired brass. Primers looked great..

The IMR 7828 loads were on some cases I bought at the gun show.... primers fell out real easy after I shot them. The cases looked near new but were probably tumbled clean then packaged.....

I now have some new brass...

quote:

Originally posted by Sendero300:

That's good info, thx.

I think I've made a major mistake with reloading the IMR powder.

I'm not sure what you mean by that.

Use of IMR 7828 is not a mistake in the Weatherby -- in fact, it's arguably the optimum powder for at least some loads in the Weatherby magnums, including the .300 Weatherby.

Yep, didn't mean that the IMR 7828 was a mistake.

I'm taking the rifle out tomorrow with more loads of IMR 7828. This time with new brass.

I think I made a mistake buying used 300W. brass at the gunshow.....

I would definitely give H1000 a shot or two. Just worked up a load for a buddy; his liked the H1000 better than the 7828----BUT he wanted to be shooting 155 grain bullets too.

God Bless, Louis

Gentlemen Be carefull what brand of brass you are using as well. Weatherby brass has a greater internal volume than Remington brass has.A max load in a Wby cases would be over max and possibly dangerous in another brand of brass. In my experience the Wby cases will handle 2 to 3 grs more powder than the Rem or Fed cases. Hope this helps.