7mm/300 wsm load data

[Ackley]

anyone use this caliber,a necked down 300 wsm case to 7mm ?? I have one but struggling to get a good load,Iam using Vit 160 and have come down to 64gr and still a fired case will not chamber as the bolt is sticky

 

[wnroscoe]

Try this link, http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=300310&fpart=1

The loads listed below are from this link

180 berger 62.7gr H4831sc wlr
175smk 64 gr rl 22 cci 200
180 berger 64gr rl 22 cci 200

 

[StevenCO]

You may want to check your dies. I have had some trouble in the past with my re-sizing dies and saw it effect accuracy as well. I got pretty good accuracy with the first round out of a case. But when I resized it, it was harder to chamber.

 

[cbonner]

I am just about finished working up my hunting loads for my Kimber 8400. I was very disappointed with the lack of quality/ concentricity of the Winchester brass. The only other new brass I could find was Norma 300 WSM. The Norma brass is excellent. However... there is more to it than just necking down the 300WSM. If you put the two cases next to each other, you will see a significant difference between the two. The neck of the 7WSM is shorter, thus the converted cases have to be fire-formed to blow the shoulder out its proper position. I also turned the necks down just enough to get a full clean-up. I am not sure it was necessary to turn the necks, but I have the tools and figured better safe than sorry.

I experimented with both 140 and 160 grain Nosler Accubond bullets and various powders,R19,R22,R25, AA 4350 and VV N560). I have finally settled upon VV N560, obtaining great velocity and sub-MOA groups. I am now putting the final tweeks on the load to minimize bolt stickiness.

Anyhow, with MY COMBINATION of rifle/ components, the sweet spot was as follows.
Nosler Accubond 140grn - 69 grains of N560 = just shy of 3300fps
Nosler Accubond 160grn - 67.5 grains of N560 = just shy of 3200fps
Obviously, I worked these loads up gradually and any attempt to copy them should be done by also starting lower and working up to a load that is safe with your combination of rifle/ components. - Craig

 

[Forum Boss]

FYI, Norma also makes 270 WSM brass, and it has a longer neck. Alan Warner and Vince Bottomley are both running 7mm-270wsms primarily because the case capacity is just a bit lower and the necks are a bit longer.

Norma Brass

.270 WSM - Product #26907
.300 WSM - Product #27676

LINK: http://www.norma.cc/content.asp?Typ=28&Lang=2&DocumentID=390&Submeny=4&Rubrik=Components&Title=Norma%20Cases