7mm saum in 7mm rem mag

rimfire458

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Got an fn 98 mauser in 7mm rem mag action. Looking for something hotter but don't have length for 7mm STW. Wonder if the fatter saum will fit and feed in box mag?
 
You would be looking at a tonne of work to the bolt face/extractor (Is it even possible with a M98?) Feed ramps would need modification, follower may need work. So basically a whole tonne of smith work for esentially zero gain. Buy a 700 and work that into a STW or RUM if ytou want more.
 
More berries but W/out length it seems I'm buggered

For what purpose? Lots of ways to get more berries out of a 7RM but it really depends on the intended use and what you are looking for. I'm all for new guns and faster guns just for fun and if you want one good on you but if you are trying to serve some practical purpose, I'm guessing the 7RM can do it just as well as any of the 7mm cartridges. It just might take a bit of tweaking.
 
More berries but W/out length it seems I'm buggered. Now 257 weath seems to be a long range stinger too

Well you sure as heck won't get more berries with the RSAUM....or with the .257 Wby. You could rechamber to 7mm Wby, and that will give you a few extra grains of capacity, but at the expense of much more expensive brass (or the hassle of fire-forming).

Stick with the 7mm RM and work up some good loads. You won't be dissapointed.
 
Stick with the rem. mag.....it should do everything you want for long range shooting. If you really want more "berries" just sell it and buy the 7 STW or 7 RUM.
 
Actually the 7mm Wby has slightly less capacity than does the 7mm RM but is loaded to a higher pressure and it does add 100 fps to the Rem mag. Secondly the 7mmX300 WM is a significant improvement over the Rem mag, I used to drive 160s at nearly 3400 fps from a 7mm X 300 and a 7mmX68 imp out of a 25" tube. The 7mm X 300 WM will do everything the 7 STW does and would work with zero mods to the 98. I was quite impressed with the gains from the 300 WM case it is not proportionate and I don't know why, I found this with several wildcats on the 300 WM case. There's just something magic about that case, my 9.3 X 300 WM is another good example as is a 35-300WM.
Anyway that would be the best and least work for a significant gain in "berries" from a 7mm bore on a 98. Do believe I have the reamer still.
 
My info shows 4gr. greater capacity in the Weatherby. (total volume-water)

Although I agree that this is not where the velocity increase comes from.
 
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Actually the 7mm Wby has slightly less capacity than does the 7mm RM but is loaded to a higher pressure and it does add 100 fps to the Rem mag. Secondly the 7mmX300 WM is a significant improvement over the Rem mag, I used to drive 160s at nearly 3400 fps from a 7mm X 300 and a 7mmX68 imp out of a 25" tube. The 7mm X 300 WM will do everything the 7 STW does and would work with zero mods to the 98. I was quite impressed with the gains from the 300 WM case it is not proportionate and I don't know why, I found this with several wildcats on the 300 WM case. There's just something magic about that case, my 9.3 X 300 WM is another good example as is a 35-300WM.
Anyway that would be the best and least work for a significant gain in "berries" from a 7mm bore on a 98. Do believe I have the reamer still.

Do you have load info for the load that drove a 160 to 3400 fps? That's pretty impressive, one would think a STW at the same pressure should be able to beat out the 7mm-300 by 100 fps or so. Not calling BS, just honestly curious. What action, any estimates on pressure?
 
Do you have load info for the load that drove a 160 to 3400 fps? That's pretty impressive, one would think a STW at the same pressure should be able to beat out the 7mm-300 by 100 fps or so. Not calling BS, just honestly curious. What action, any estimates on pressure?

A 7mmSTW could probably get close to 3500fps with a 160 gr bullet, running about the same pressure as the 7mm-300WM needs to make 3400fps with the same bullet, but there is no way that I would ever load it, or any other rifle, to that type of pressure. However , with the right lighting conditions, I could probably get a Chrony to read that high with some loads, that are somewhat close to reasonable.
 
My info shows 4gr. greater capacity in the Weatherby. (total volume-water)

Although I agree that this is not where the velocity increase comes from.

My book says 4.3gr more capacity for the 7mm Wby, plus it has a 4000 PSI higher operating pressure (65,000 vs 61,000). On paper it gives the Weatherby a fair edge.
 
A 7mmSTW could probably get close to 3500fps with a 160 gr bullet, running about the same pressure as the 7mm-300WM needs to make 3400fps with the same bullet, but there is no way that I would ever load it, or any other rifle, to that type of pressure. However , with the right lighting conditions, I could probably get a Chrony to read that high with some loads, that are somewhat close to reasonable.

A couple of things here stubblejumper, A....I don't use a Chrony I use 2 Oehler 35Ps, and secondly I don't load till I blow primers, these loads were not only safe in this rifle but my brass showed slight pressure indicators but was usable for at least 4 loads. I'm not where I can review my load data at this time but if I remember correctly it was using IMR 7828 and CCI 250s with a 160 Nosler Part. The rifle was a 700 Rem.
 
I don't load till I blow primers, these loads were not only safe in this rifle but my brass showed slight pressure indicators but was usable for at least 4 loads.

"slight pressure indicators"?"at least four loads"? A fair amount of testing by people using actual chamber pressure measuring equipment, has shown that by the time that you see any high pressure indications on brass, you are already in the 70,000psi to 80,000psi range. Using your idea of "safe" loads, I could no doubt get 160gr bullets out of the 7mmstw at well above 3400fps, but my idea of "safe" loads is obviously far different than yours.
 
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