Reloading 7MM STW (Belted Cases)

T

topwater225

Guest
My question is more about "Belted Cases" than "caliber"..., but here goes:

I am not new to average reloading, but I want to take my reloading to the "precision" level for long range hunting/competition.

I just ordered a new custom rifle in 7mm STW (belted case), and I want to be sure I do the reloading steps right without re-inventing the wheel. So, here are the steps I envision performing. And I would greatly appreciate if some of you would verify/correct my theory.

Brand New Brass: After Purchasing the Redding Competition Die Set (FL, Neck, Micrometer seater) and the Stoney Point Head Space Gauge.

1. Take new brass and FL size using the expander ball to get dents out. Priming will be done at this stage as well.
2. Check case lengths and trim if necessary to get all brass at min length (2.84"), and make sure no particles of brass is left in the case.
3. Fill cases with powder using trickle method to make sure all loads are consistent.
4. Insert the Micrometer seating die.
5. Using dimensions that the gunsmith gives me ; seat 175 SMK or 180 Berger to lands.

Fired Brass:
1. Check fired brass with Stoney Point Head Space Gauge.
2. Remove expander ball as this is only used for New Brass. (I don't know if the expander ball can be removed without removing the de-capping pin....I need advice here...)
3. Check case lenght and trim as needed.
4. Set the FL sizing die to just "bump" the shoulder back to the desired length and decap and re-prime (Again, what is your opinion here? If the expander ball and de-capping pin can not be separated, should I perform de-capping with a different kind of die, and should I be "hand priming"?

Now.... I'm really fuzzy on the redding neck sizer and if it's even needed, but here goes:

5. Use the neck sizing gauge to re-size just the neck (This maybe unnecessary as the FL die probably sizes the neck). I need advice here too....
5. Fill cases with powder using same trickle method as above.
6. Seat Bullets to exact dimensions.

All opinions are welcome, and thanks in advance!!!
 
I reload for my 7STW with a neck sizer on fired brass.

I use a neck sizer I set with trial and error on once fired brass, measuring, neck sizing and firing.

I do not have a procedure, but to start with, I run it down until it reforms the neck, almost to the neck shoulder intersection. My die is locked, and my brass lives through about 5 cycles. This is not a problem, since I do not shoot this rifle a lot, except at deer and moose.

If you go too far down with a neck sizer, you can see it start to deform the shoulder.

I prefer IMR 7828 powder in my STW.
 
Reloading 7mm STW

Topwater,

You didn't mention what brand and style of dies you have, if they are not bushing type, you probably will want to have some type of bushing neck die at some point. The Redding "S" full length size die allows you to select the size of bushing that sizes the neck exactly and sizes the body at the same time. The Redding body die sizes the body of the case only and leaves the neck untouched to be resized separately. However you accomplish this, you need to carefully adjust your full length die to set the shoulder back .001 to .003. The Stoney Point tool that fits on a pair of calipers and measures from the base of the case to the datum line on the case shoulder is a perfectly good way of doing this, and much more precise than trying to gauge from bolt closing resistance. The primer in the fired case tends to protrude slightly and may interfere with getting an accurate measurement unless you decap first. You could just use a punch to decap a few cases to get everything adjusted and then decap the rest of them as you size.

The overall length your gunsmith gave you is just a starting point. All bullets vary a little from lot to lot so you need to check the seating depth to find the point where your bullets touch the lands in the throat. You can seat a bullet to the length your gunsmith gave you, chamber it, remove carefully, and inspect for rifling marks on the bullet. It may help to use a felt tip marker on the bullete to make the marks easy to see. With experience, you can judge how deep into the lands you are by the width of the marks. If you have a Stoney Point OAL gauge and the correct case you can use it to get a starting point which will be the point where the bullet just starts to touch. Your best seating depth may be a little longer, or you may find a seating depth slightly off the lands that shoots well.

I would start with the bullets just touching, find the powder charge that seems to produce the best groups, and then try seating longer and shorter lengths to find the best seating depth.

The 7mm STW is not as popular these days as when it was first produced, being overshadowed by all the ultra mags, short mags, etc. but it is a very accurate cartridge and my experience has been that it is easier to get it to shoot and somewhat less troublesome than most of the others. I hope you have good results with yours. Hodgdon H1000 seems to be the powder to use with the heavy bullets, but other very slow powders may work as well.

Scott
 
i'm not a competitive shooter, however if your luck runs anything like mine from my hunting perspective i always fl resize my hunting loads. its one thing to have a stuck case at the bench its another to watch a trophy running into the horizon with a stuck case in the gun.
my stw just loves 7828
 
Thanks to all!

I'm just about ready to purchase my dies, and I am thinking about going with the Reddings "S" FL die with the bushings, and the Competiion Seater.

Does anyone see any issues with these die choices?
 
7mm STW Die Choice

Thanks to all!

I'm just about ready to purchase my dies, and I am thinking about going with the Reddings "S" FL die with the bushings, and the Competiion Seater.

Does anyone see any issues with these die choices?

Those are the dies I would use. If you are not neck turning your brass you will probably use about a .309 bushing. My loaded cartridges measure .311 at the neck with Remington brass.

Scott
 
somewhere in the first working I uniform the primer pockets and flash holes, I also sort by weight( staying with in 1-1.9 grs.) my 2 STW's one loves retumbo the other H4831SC,140 gr accubonds or 140serria gamekings about .008-.012 off the lands, I also turn the necks enough to clean and uniform
 
terryhawk said:
i'm not a competitive shooter, however if your luck runs anything like mine from my hunting perspective i always fl resize my hunting loads. its one thing to have a stuck case at the bench its another to watch a trophy running into the horizon with a stuck case in the gun.
my stw just loves 7828
Click to expand...

Why do you need a second shot with a 7 STW?

It will kill anything big enough to die.
 
alinwa said:
I'm certainly not a fan of the belted mag cases but if I DID want to shoot a belt I'd strike up a relationship with Larry Willis............. this guy >>> http://www.larrywillis.com/ <<<


al
Click to expand...

Al,

No one has never given me a good explanation of what steers them away from the belts. I've read a little this/that about head spacing etc. But I still see 300 mag and a few other belts showing up on the heavy/light gun score cards and stuff. And god knows, it's a helluva big game taker.

I think you have a good insight on some of these subjects, from reading your other posts.

What's the deal with belts? Why not a fan?

Ben
 
Bnhpr,

Belted magnums have won lots of wood because they're what's been available. In the large capacity case we've traditionally been stuck with several choices, none are ideal;


---using good brass and living with a belt
---using extremely hard to get European brass
---or going with a decent chambering and living with crap brass


You will find that prep'ing, producing and maintaining belted brass for the long-term is well nigh impossible. The belt precludes good resizing EXCEPT if you use Larry's die which offers a reasonable fix for a problem which shouldn't exist. Why do you think that folks have taken the time to lathe-turn the belts OFF of belted mags for years?


Because they SUCK!


What the 1K world needs is a large capacity, non-belted RUM sized base case mfgd by Lapua. (A "base case" is a case upon which to build wildcats. F'rinstance, I ordered 500pcs of the new 6.5X47 brass 6mo before any arrived in-country.........I'll probably never use it in its original form, it's a "base case", I've got two reamers built off of it but will probably never shoot the 6.5 itsownself)



al
 
alinwa said:
Bnhpr,

Belted magnums have won lots of wood because they're what's been available. In the large capacity case we've traditionally been stuck with several choices, none are ideal;


---using good brass and living with a belt
---using extremely hard to get European brass
---or going with a decent chambering and living with crap brass


You will find that prep'ing, producing and maintaining belted brass for the long-term is well nigh impossible. The belt precludes good resizing EXCEPT if you use Larry's die which offers a reasonable fix for a problem which shouldn't exist. Why do you think that folks have taken the time to lathe-turn the belts OFF of belted mags for years?


Because they SUCK!


What the 1K world needs is a large capacity, non-belted RUM sized base case mfgd by Lapua. (A "base case" is a case upon which to build wildcats. F'rinstance, I ordered 500pcs of the new 6.5X47 brass 6mo before any arrived in-country.........I'll probably never use it in its original form, it's a "base case", I've got two reamers built off of it but will probably never shoot the 6.5 itsownself)



al
Click to expand...

Ok, my brass doesn't last with my STW, even with neck sizing, but I run a hot load in it. I'm now in conservation mode with it, because I love to hunt with it. My barrel will not last.

I have a 300 mag and 300 RUM reamer now. Some people really like the 300wsm too, but, again, no brass.

I hate to become part of the herd, it's against my trial and error nature, but I'm now looking at the 6.5x284 to get into some long range stuff.

thanks

Ben
 
After 5yrs of stalling I just kicked off a 30cal project using the 300WSM as my base. I've got the reamer in hand based on the Redding 300WSM die and will be using Winchester brass.


Win brass aint bad. Lapua would be better but they've got no plans for a big non-belted case AFAIK.


al
 
Fellow Shooters,

I could write a book on belted magnums. In fact, I wrote almost a whole website on this subject. The reason a belt was invented, was to provide a forward stop on the super tapered H&H magnum cases. The belt was NEVER needed except on (2) H&H calibers. All the rest of the belted magnums got belts added for marketing purposes. Arms manufacturers thought that the success of the H&H belted calibers were so great, that no magnum case would even be noticed if it didn''t have a belt. Contrary to popular belief, there's no strength added with a belt. The belt is located over the solid part (web) of the case.

The problem with the belt is that it limits the travel of any FL die. The slightest downward pressure during reloading causes the weakest part of the case (the pressure ring) to bulge - even if you NK size. Headspace (length) isn't the only consideration when resizing a tapered case. Think about it . . . . tapered cases . . . . you can get most rifle handloads to headspace on the case wall (width problems) if set your dies too high. Remember the belt limits the travel of a FL die,and that's what makes belted calibers different to deal with. NOTE: Headspace gauges NEVER check case width.

The symptoms you can see after loading belted cases a few times, include tight chambering (that's tough on your bolt lugs), fail to chamber (that can get you killed when hunting dangerous game), fail to extract (that can make your rifle totally inoperable after one shot).

After making (4) prototype dies, I've found the best way to resize belted cases is with our Belted Magnum Collet Resizing Die. The U.S. Secret Service and over 2,200 shooters agree. The top of this die measures the case width, and if your case fits down to the belt - you don't need to use it. However, if your cases don't fit, why would you not want to use it?

- Innovative
WWW.LARRYWILLIS.COM
 
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