Loaded neck diameter and dies for 7WSM (or 7mm/270, 7mm/300WSM)

[maxpower]

I have decided to go for a 7WSM of some sort for my 1000yd lightgun and will be ordering a reamer soon. Can anyone tell me what the loaded neck diameter is with Win brass in 7MM, or with Norma 270 or 300 brass necked up or down?
Also, does any one make dies for 7mm/270WSM or 7mm/300WSM chambers?

 

[scout1]

Do you plan to go with a straight 7 WSM or opt for the longer neck of the 7-300 WSM. PTG or Dave Manson will make the reamer to your spec or go off of an existing print, theres plenty out there to choose from either way you decide to go.

Standard 7 WSM Win Brass loaded with a 162 A-max measures .314

 

[ar1957]

I would have a pacific Tool 7mm WSM match reamer ground with a .315 neck and .189 freebore length. I can tell you it works great just touching or at .010 off over 90 deg with high humidity. Just my 2 cents.

 

[maxpower]

I have found a gunsmith in my area with a 7mm/300WSM reamer with .310" neck. Now I just need to find someone who makes dies to suit. I can get a seater and neck die made with the chamber reamer, but will need a FLS die made up.

 

[TonyR]

One option would be a Forster FL die then have them open up the neck to your specification. I believe they will do this for about $10.00 plus the cost of the die and shipping. Here is how one person did it:

http://bulletin.accurateshooter.com/page/3/

I went another way on a recent project. I measured the neck on a standard FL die and had the chamber reamer ground for the loaded neck and neck tension I wanted. I use a 0.310 loaded neck with a 0.313 chamber neck on my 284 Shehane with a 0.309 neck diameter in the FL die but you could get pretty much anything you wanted within the limits imposed by the thickness of the brass neck walls and the diameter of the bullets.

 

[maxpower]

I will need to go the other way, get a 300WSM die made smaller. I didnt want to ust use a smaller bush as it will leave a portion of the neck at the 300WSM diameter, not necked down for 7mm. I will phone them and see what they can do.

 

[TonyR]

I have been preparing 7mmSAUM brass from 300SAUM brass like this:
I make one pass through a Redding 7mmSAUM neck sizing die with a 0.327 bushing then a second pass through a Forster 7mmSAUM full length sizing die then expand with a mandrel for the neck turner. I would think you could do the same thing with the 300WSM brass with appropriate dies. The resulting necks end up shorter than the necks on Remington 7mm SAUM bulk brass which also may be true with WSM brass. I had the chambering reamer ground for the shorter necks so if I use Remington brass, I will have to trim them during the initial prep.

 

[maxpower]

Problem with the 7mm/300WSM is a short body but longer neck. So If I use a std 7mm die, it will be too long, wont push the shoulder back. If I use a 300WSM die with a smaller neck bushing, it will leave an unsized portion of the neck.

 

[bingo1010]

surely someone must make 7/300 wsm dies so you can size the full neck?

 

[Yellow11]

Since these previous posts - has anyone got a source for such a die?

 

[scout1]

If a 7WSM is this much of a hassle with the only bennafit being a longer neck I'd say scrap the idea and go with the straight 7 WSM. I had no problems finding everything I needed for mine without custom special orders.

 

[JFrank]

Wilson makes sizing Dies and seaters for those calibers your asking about.

 

[whatwind?]

just use 300wsm sizing dies with proper bushings .310 etc and regular 7wsm seating die....but, there is a nice custm set for sale in this forum right now

http://forum.accurateshooter.com/threads/reduced-7-300-wsm-matching-reamer-set.4012659/