I saw Cabelas has Norma 300 WSM brass in stock. My question is, can I form 7mm WSM brass from this by simply necking down and fireforming?

Thanks,
hillbilly willy

No because the 7 MM WSM is a longer case to the shoulder.

Grafs has WW 7 MM WSM brass in stock and so do many local shops around here. www.grafs.com

I disagree.

The differences in the 7 and 300WSM is .037" body length and I think it would be a minute feat to control moving things that little.

If you set up your sizer to allow a snug chamber fit,you'd reliably control headspace and could move that much brass easily.

The differences betwixt the 270Win and 30-'06 are greater than that(on the order of .050")and using the '06 hulls to yield 270Win brass is amongst the oldest of practices.

I'd say if you were hot on the Norma brass,then give her a whirl.............

You did not read,what I wrote.

The difference in case body lengths between the 270Win and the '06,is greater than the differences between the 7WSM and the 300WSM.

Also mentioned that headspace could be easily controlled in the 7WSM's chamber,by setting up sizing die geometry to gain some resistance upon bolt closure ala the resized Norma 300WSM virgin brass(an effective means of establishing headspace,when forming so minutely).

Never mentioned anything about trim length in general,nor headspacing the case mouth in particular,nor anything remotely touching upon the 30carbine round.

After sizing properly in the 7WSM die,them IS the "right" cases and of course that was both my initial and subsequent point..............

Even fireforming you'll NEVER get the 300 WSM to stretch out to the 7 WSM body without seriously stretching the body near the web. That will be the beginning of incipient separation and the cause of early death for it. That is the reason for the early demise of most belted magnum cases which usually only stretch initially from .015" to .024". You can put a false shoulder on the neck, grease the front part of the body, or anything else you want to try, form without a bullet using a filler, but it will still stretch at the web on the first firing.

The amount of brass movement and the distance is minimal in the grand scheme of things.

Glad my 25-06Ackley don't know that it can't eagerly digest '06 hulls in the same manner(false shoulder and bullets engaging the lands while forming),while still realizing a long case life and never suffer a head seperation.

It is a very modest forming operation..............

(Should add,same goes the 280AI,with it's longer body length,again on the order of .050")

[ 02-17-2003, 06:56: Message edited by: Big Stick ]

Hillbilly,

If you want to use the good Norma brass you cand size the neck down a little at a time to 7mm and headspace off the bulge at the base of the neck. If you want to be sure the case stays back against the bolt and doesn't stretch the body and cause early seperation "lightly" lube the cases, seat the bullets into the lands, leave the step on the neck and fire these two or three grains under your normal safe load to fully form the new improved shoulder. It isn't a new thing I'm describing, it's used all the time and will not stretch the case, but rather alow it to move back (if it moves forward to begin with) without doing so.

Another thing that would warrant attention,is the differences in internal capacities between the W/W hulls and the Norma offering. Not having the Norma onhand,I can't offer input to the differences,but would make a determination prior to load development as a safety concern.............

Brent, even with the false shoulder, I have had the devil of a time to keep from stretching at the web. My suspicion is that a 30# fall by the firing pin is enough to size the brass, and create headspace.

In the little experimenting I have done, seating a flat-based bullet backwards, heavy into the lands, gave the least stretch at the web. I learned this trick with some Norma 7mag brass that was >.05 short to the shoulder. FWIW, Dutch.

Hey Dutch,

How far into the lands were you seating them with the bullets seated the normal way?

Notice any accuracy improvement with em in backward?

Here's a post a while back of Steve's along with an interesting experience using the same method.

Moving a shoulder forward method,

If I'm blowing a shoulder forward while fire-forming like I do for the 338 Yogi(approx .050" the shoulder moves forward) then I use my regular load minus 2 grs of whatever powder your using and lightly lube the outside of the case body and neck with Imperial Sizing-Die Wax. Normally jsut enough wax so that your finger tips look shiny is all. Then EVENLY spread the wax over the entire circumference of the case body and neck. Seat the bullets long to hold during intial chambering. What this does is allow the brass to expand against the case walls but not stick for those few milli-seconds and allow the case as a whole to slide back against the bolt face and not stretch the brass. Yes this does create more thrust on the bolt during firing. I've never done this on anything but good commercial and custom actions. Would I do this with a 30-40 Krag rifle with an improved chamber for example?..... no! I've had guys argue with me tooth and nail that this is dangerous and I'll blow my head off. I've also talked with many others that have used it for many years and some are prominent gunsmiths. So it's up to you. Just realize what you are doing and be willing to accept the risk if there is any. NOTE: remember that it is important to keep your locking lugs lubed while doing this or you take a big chance of galling them. Especially in SS actions.
Here's is a perfect example of how this work and that it really does work. 2 or 3 yrs ago, during a competition I normally fire my first 2 or 3 sighters with my fire-forming load that has lubed cases. Due to the oily bore and such the first 1 or 2 sighters are very course sighters anyway so the accuracy/drop isn't that important. It will hit lower so I jsut don't click down that much. In this particular match I was fire-forming all 10 sighters and my match load was 2 gr hotter. I needed those case fire-formed for an upcoming aggregate match. But in the confusion of getting everything setup and my other duties during this match, I forgot to lube all 10 of my sighter(fire-forming) cases. Well, I fired all the sighters and record rounds without a problem. They all fire-formed fine by the naked eye and nothing unusual.
Then a couple days later I resized all of the cases I fired in this match and the sighter cases felt different during sizing. Then I put them in the case trimmer and after the first case realized something was different. It was cutting off .010-.012" off the OAL. Normally this is only a cleanup cut to make sure they are square. At most I might get some shavings. But noramlly just barely a skim cut. This happened to all 10 of those sighter cases. So the wheels were turning in my head as to what is different. Then I realized what happened really by accident a little later on. I ran out of sizing wax that I keep on my loading bench. I went to my shooting box to get my "traveling" can that I take to the matches. I couldn't find it in my box. I found it on my shooting table and I hadn't opened my shooting box after returning from the match until then. So the "traveling" can of wax never went ot the match with me and because of that I never remembered to lube my cases.
So that extra .010-.012" is case stretch from within the case from the brass "holding" against the chamber walls during firing and pushing the shoulder forward and/or the case head backward. The real kicker happened a couple ofweeks later during another match when I had my first case retire out of the original 100 Lapua 338 Lapua cases I purchased. Then another. Within a 2 week period I had 3 case failures (cracked cases around the shoulder/body junction) on 5 firings or less. I number my cases with a majic marker and keep track of the them in a spreadsheet so that I know what cases were used and at what match. Well, those 3 failed case came out of that batch of 10 unlubed cases!
To this day of the original 100 cases I bought, I've fired them many times (wore out one throat and had it setback and rechambered and started firing again on the same cases) with over 20 loading on some of those cases. I've lost 5 cases out of that batch since 1999 in my 338 Yogi chamber. 4 of them were case body/shoulder cracks out of that batch of 10 unlubed case. The 5th is a cracked neck from fatigue that wasn't in that batch.

Dutch, did the Norma 7mm rem mag cases hold less or more powder or water compared to Winchester? What did you notice about Norma compared to others in a negetive way? I plan on reloading with Norma 7mm rem mag brass this spring and I want to be prepared for any downfall.

Lot's of good insight here guys, but it seems I'm no closer to an answer. I guess there is only one way to find out!! I guess I was hoping someone had already done it. I was already aware of the differences in the cases. This is the reason I was asking. Seems to me it wouldn't be much different than fireforming AI cases. This I have done by simply seating the bullets hard into the lands and firing a mild charge.

It seems the brass would have to expand too far with the 300 brass in the 7mm chamber. I think I will try forming the false shoulder and firing with a mild charge. Which brings me to my next question, should I trim to length after necking down or wait untill after they are fireformed?

Hillbilly

The 7mm is longer than the 300 by .035", you are necking down, this would seem to cancel each other out, as the case will grow. But the case length will be reduced because of the shoulder being blown out. This will eat up some length.
I would wait to trim without a doubt.

If you lube the case and seat the bullet plenty into the lands using as much a false shoulder as you can (which won't be much in dia.) you should do fine. The lube will keep the case from gripping the chamber and the cases won't stretch.

I'm fixing to go through the same routine on a 300/338 Lapua Improved using 338 Lapua brass.

I routinely move much more brass,when forming 375H&H Ackley hulls,via fire forming 375H&H in that chamber. Have even formed 30-8mmRemmag hulls,by firing 300H&H hulls in that chamber. Case seperation has yet to raise it's ugly head.

Point bein',what you are after,is easily attained and borders on the mundane................

I figured for sure that Hillbilly would not be back after his first post what with some of the ramblings above.

Hillbilly,

Drop the idea of using .300 WSM brass. Just do this ok? Go to www.grafs.com/BulkByBagQty.cfm/startltem/1

The order will cost you $21.34 total including shipping delivered to the 48 states. They will ship it today if you get the order in soon and you will have no sizing to do at all and have the right headstamp.