7mm-300win

[calib]

Anyone here running this round and if so are you pushing the 180 grain berger? I am gonna have one built and would like to find some info for it. I have read some posts on other forums, just like some of the info I get from here.

[darkker]

No, but maybe.

I'm running the 6.5mmX300 WSM.

Wolfe Publishing has a "Wildcat Cartridges" book that has tons of 7mm Mashburn load info.

[calib]

no one here playing with this round or something similar?

[Blue Avenger]

why not go STW, easy to find dies, brass and load info.

[calib]

brass is not any easier or cheaper to find and really the dies are not hard to find for the 7-300win

[Blue Avenger]

factory stamped brass? In both cases all your doing is drilling the standard 7RM chamber deeper. case capacity is the only change.

[calib]

the 7 stw brass not made is not easy to find rite now, i am sure there is almost the same steps involved in making either cartridges. just neck down the parent case rite?

[darkker]

Just neck down the parent case rite?

Although not positive, I think the Mashburn Pre-dates the win mag. Otherwise, yes.

[Blue Avenger]

yup, I have formed 300wm to stw and get 1/8" of neck so not a big difference.

[r3dn3ck]

edit. note to self. use better google foo

[calib]

well once i get the cartridge and gun going ill let you guys all know how its working out along with how the nitride is doing, maybe then some people may be interested in the round.

[Skunce]

I'm shooting a 7mm SAUM that is throated long for heavy bullets and I like it a lot. The Rockchucks don't like it much though. There is some good info on the 7-300 WSM and the 7mm SAUM on the accurate shooter site.

[calib]

not the same, but thanks what bullet are you running?

[35Whelenshooter]

I'm looking at building a 6.5X300WSM what are you using for a tube? twist? how long tube are you using?

[calib]

not really the same again, but i am getting a 28" mcgowan 1:9 twist

[35Whelenshooter]

Thanks, I like the wildcats in 6.5MM

[yobuck]

ive been using a 7x300 for about 40 years. mine however is built on the 300 weatherby case. that cartridge has been a very popular
one among pa long rangers like myself for many decades. the 7 stw is about identicle as for performance. simply run the standard 300 weatherby case
thru a 7x300 die and its done. rcbs makes the dies. i believe redding does also. velocities of 3350 with the 162 amax are common. using powder like 7828 a 28"
barrel will suffice. 1 in 9 would be a good choice and would allow for heavier bullets if desired.
i also have a 6.5 built on the 270wsm case. velocities are similar using a 140 also in a 28" 8 twist barrel.

[35Whelenshooter]

Thank you for the information on that yobuck. I'm new to this.

[calib]

got my bushing dies and sized 100 pcs of brass. never used bushing dies, but i think i may get to like them a lot

[wbm]

why not go STW, easy to find dies, brass and load info.

Indeed! Fast, Deadly, Accurate!

[Axtell3]

I was reading up on this subject. Search 7mm Jarrett.

[scpaul]

Try Nate Foster 7mm Practical & Snipers hide.com. It's a little different but look at 7mm Valkerye. I'm in the process of building one of the 7mm/300win variations. I've got everything but the bbl,dies &go/no go gauges. Paul

[yobuck]

for those seriously considering the 6.5 wsm cartridge.
first off buy norma brass as it will take the pressure better than winchester.
trust me on that i paid the price with ejectors and scorched bolt face.
i would also reccomend starting your build off a short mag action if using a savage.
that is if your planning on using the magazine. dont put yourself thru the grief of making
another work properly.