7x300 weatherby magnum

[zorak]

Just finished my load development in the new 29" Bartlien barrel with 1/8 twist. Here are some loads that work well.
US869 87.5 gr. 195 Berger 3,143, Hornady brass with CCI 250 primer. c.o,a.l was
3.868".
H870 87.5grs. 180 VLD, same primer and brass, Mv was 3,250, c.o.a.l. 3.800
RL33 85.0 grs. same primer Norma brass 180 VLD,
,3187, C.o.a.l. 3.840.
I am going up with the 180 and 195 and with Hornady 300 H&H brass which is much stronger. I have tried Magnun and RL26, IMR7977 with good results.

Careful pushing the VLDS over 3200pfs. My gun smith said the start to get lead sag or bulge and start really srubbing off the copper causeing excessive copper foul. I found my best load is 80.5gr of retumbo, cci 250's amd nosler brass with the 180 vld hunters at 3.707 c.o.a.l.

I dont like the hornady brass cause they are not as consistent in weight as the nosler are.

 

[kendoka66]

Careful pushing the VLDS over 3200pfs. My gun smith said the start to get lead sag or bulge and start really srubbing off the copper causeing excessive copper foul. I found my best load is 80.5gr of retumbo, cci 250's amd nosler brass with the 180 vld hunters at 3.707 c.o.a.l.

I dont like the hornady brass cause they are not as consistent in weight as the nosler are.

I have not had any weight problems with Hornaday 300 H&H brass. I find it much stronger in the web area than any of the other makes.
I have not had any copper build up as yet at 3,250fps. with the 180 hybrids or Vld,s.. The 175 Nosler Accu bond L.R. at 3280 is a great big game bullet.

 

[JLT]

WC872 is a surplus powder and you should be able to find it where surplus powder is sold.
In my 300 wby a max load with WC872 was about 100 fps slower in my rifle than h870 but the accuracy was slightly better with the WC872, in the 7x300 wby it was a little bit slower but I don't remember how much. It is a good powder and compares favorably with h870 and the price is right.
Drags

WC870 is also available. It's the same as H870, just not canister-grade. There may be some lot-to-lot variation in burn rate. Check out www.gibrass.com. Inexpensive, too.