Anyone running a 7mm/300 WSM? Thinking this may be my next build. Is neck turning neccesary when necking down 300WSM brass?

No neck turning required unless you have your chamber cut with a tight neck.

Why the wildcat 7mm/300WSM rather than the SAAMI 7WSM?

Depends on reamer dimensions, brass will thicken slightly when necking down, but you may still get by without turning, and add me to the list of wondering why not just go with the standard 7mm WSM?

Easier to get brass. Also read it was more effiecient & easier on throats according to the article on 6mmbr.

It's pretty easy to buy all the WW brass you want for the 7WSM.
If you prefer other brands of brass then yes there are more choices for 300WSM brass.

As to being easier on throats that would only be because it's slower than the 7WSM. There is no magic in the 300WSM case which is lost when the shoulder is pushed forward .038".

Why not just neck down 300WSM brass and use it in your SAAMI 7WSM? That's what I'm doing...

False shoulder.

Exactly. What's the problem?

No problem here but you are aware that the 7mm/300WSM is easier on throats and more efficient than the regular 7WSM aren't you?

you have my vote for the lame wildcat award

You have my vote for biggest idiot on this thread.

Some of you guys should reread my first post, I wasn't asking for your thoughts or opinions about the cartridge.



As for the brass its available now, but there was none to be found a few months ago when I started thinking about this project. I believe it's a seasonal run item.

Finally I already have a 300WSM bushing die, couple new bushings & I'm set for dies.

...uhh...what was the questions again? I was busy rearranging my sock drawer.

Easier on throats? Seriously? Oh boy, this should get good. Flinch

Well, since Winchester is going to be chambering the Model 70 in 7WSM, I think brass will become more available.

If the 7mm/300 WSM had a radically steep shoulder I MIGHT believe the throat erosion would be reduced. The small difference in case capacity between the standard 7 WSM and this wildcat are so small that there would be no way to prove any wear differences.

At least you have a way to size the brass with available dies. You will still have to buy reamer unless you found a gunsmith with one.

Seems like alot of work for nothing.

Why complicate things ? I have a custom barreled 7 WSM and its "Bad to the Bone" just they way it is.

Prolly old news, but Norma just shipped their lot of 300WSM brass to the US. Had been waiting for it to neck down for my 7. Rifle is new, and found it hard to get good brass from WW. Tried the 300 WSM from Federal and still wasn't satisfied. It would be nice if some good 7WSM brass would come down the pike. Got my Norma from Graf's.

I have one. I absolutly love it. Its got a tactical chamber which is not tight but requires a light turning of the neck. I use Redding Comp dies and my smallest group to date was a 3 shot .416 group at 356 yards. Lawton Single shot action, Brougton Barrel, Mcmillan Baker Special, Jewell Trigger and a S&B 5-25 PM2 scope, Badger rings and Lawton base.

Built by American Precision Arms

I take it you don't have a 7WSM. I have found that the W-W 7WSM brass is terrible. It is a PITA to create 7-300 WSM brass compared to just shooting and reloading.

I would MUCH prefer to have a 7-300WSM than a standard 7WSM. As far as neck turning- a standard 7WSM neck is big enough that the 300 brass necked down does not need to be turned. Make sure your chamber is accomdating. As the person who will chamber it how big the neck is, measure a loaded round and make sure you have .004" total clearance or more and it won't need to be neck turned. Less than that- no guarantees.

Not any more but I did and I loaded for it too.
All my WSM's went down the road. Their supposed charms are apparently lost on me.

Exactly