7 wsm vs 7 rsaum-- that is the ?

nelsonic

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Mar 12, 2005
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Ive ordered all the significant parts for my 1000 yd rifle...I still cant find enough info on which case is the best to use?! Of course I'm still able to choose as the barrel hasnt arrived. Please help me out and tell all the pluses and misses of both!! Thanks
 
better brass WSM,better suited for short action RSAUM,,I doubt either is much if any better than the 280AI.
 
I was considering the same about 2 years ago. I ended up going with a 7WSM based off a 270WSM Norma case. Kirby (Fiftydriver) did the gunsmithing. his reamer for this chambering has a very long throat making it not suitable for a short action, but if you are building a single shot or have a long action it is an incredible round. it is throated perfect for the 160gr Accubond my rifle fires them at 3185fps recently I have been testing the 180gr Berger at 2895fps with a standard deviation of 3, a B.C. of .684 making this combo hard to beat at 1000yds.
UB
 
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better brass WSM,better suited for short action RSAUM,,I doubt either is much if any better than the 280AI.

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The SAUM actually has exactly the same case capacity as the .280AI. If you look in the Nosler #5 manual you'll see that the load data for the SAUM and .280AI are also nearly identical (as is velocity). One just functions out of a Short Action, the other doesn't.

Also, in regards to throating a WSM long to achieve better performance, I believe that is a misconception too. You can throat them longer to accept VLD style bullets and function out of the magazine... but increased velocity is not usually achieved. There's an article in Rifle magazine by Chub Eastman of Nosler where they chambered a barrel with the standard WSM reamer and then re-chambered it with a longer throat and saw virtually no increase in velocity. It would help to throat it long if you were designing it to shoot the heavier VLDs I guess, although I don't know how much. ~JT
 
I'm no expert on the subject, but I think 3185fps with the 160g AB and 2900fps with the 180g VlD is a substantial increase in FPS vs. the standard WSM throating and the long throated version uncleB is talking about...

In other words, no regular 7 WSM is going to achieve those kinda velocitys in a standard production rifle...Thats at least 150fps faster then what there usually running with those bullet weights...
 
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I'm no expert on the subject, but I think 3185fps with the 160g AB and 2900fps with the 180g VlD is a substantial increase in FPS vs. the standard WSM throating and the long throated version uncleB is talking about...

In other words, no regular 7 WSM is going to achieve those kinda velocitys in a standard production rifle...Thats at least 150fps faster then what there usually running with those bullet weights...

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My factory 7mm WSM does about 3150 fps with 150 Nosler partitions and barely breaks 3000 fps with the 160's.
 
I don't think the slight increase in throat length is responsible for the 150fps gain there... heck, going from standard to AI gets you about 150fps. Furthermore, the VLDs are usually seated into the lands, or very close to them... so the only advantage is not having as much bullet in the case. You think that .25" less bullet can increase case capacity enough to get 150fps... I think not. Increased pressure, twist rate, moly, fast barrel, barrel length, good load... a lot of things could contribute to the extra buck-fifty... but to attribute it to the slightly longer throat would be a real falacy. ~JT
 
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I don't think the slight increase in throat length is responsible for the 150fps gain there... heck, going from standard to AI gets you about 150fps. Furthermore, the VLDs are usually seated into the lands, or very close to them... so the only advantage is not having as much bullet in the case. You think that .25" less bullet can increase case capacity enough to get 150fps... I think not. Increased pressure, twist rate, moly, fast barrel, barrel length, good load... a lot of things could contribute to the extra buck-fifty... but to attribute it to the slightly longer throat would be a real falacy. ~JT

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.25AOD,
I dont mean to flame you on your two posts, but you could not be more wrong if you went out of your way to try.
The longer throat is exactly what gives this round its added velocity.
In my opinion the problem with WSM and SAUM is that the SAAMI spec O.A.L. is very short so your bullet is taking up a great deal of powder capacity, with the chambering that fiftydriver did for me the bullet is not taking up any powder capacity because it is in only the neck. the SAAMI spec O.A.L for a 7WSM is 2.860" the O.A.L. for my chambering is 3.230 making a difference of .370" if you add in bullet diameter of .284" ,that is a lot of powder capacity. I will let some mathematical genius figure out how much.
UB
 
This is exactly the reason why, for a FACTORY rig, I went with 300WM over WSM. The WSMs are great cartridges but it takes a custom gun in a long action to take them to their potential; and the 300RSAUM never really caught on so there goes the advantage of readily-available ammo.

In a custom gun, WSM over RSAUM hands down.
 
Either way uncleB, your getting 150-200fps faster then you would with the factory 7 WSM, cant complain about that!!

I would love to have a custom built 7 WSM, it would pretty much be the perfect all around game getter IMO.

I am hoping to try the 180g VLD soon. I am hoping to get 2850fps out of my 24" 7 RM...I have a good load worked up with the 168g VLD at 2950, and I talked to Walt Berger and he said I wont gain anything in going to the 180g out of the 7 RM. Maybe I should just listen to him and stop there, ha ha!!
 
The WSM's are loaded to higher pressures though. In Quickload, believe it or not, the 7 WSM outdoes the 7 RM in same barrel length's!!

There is a lot of things that go into it though however, I wont argue about that. I just know from what I read, custom built rifles w/ long throats tend to thrown them bullets out at least 100-150fps faster.

The WSM's are really limited to magazine space, seating a 168-180g bullet is handicapping the cartridge in the factory chambering. With a longer OAL, it will easily outdo the 7 RM because it operates at higher pressures.

I just think the 7 WSM is a pretty kick butt cartridge actually...The 7 Rm is not far off, but for a short action 7mm, the WSM is hard to beat. Put in a long action, its even harder to beat!!
 
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I don't think the slight increase in throat length is responsible for the 150fps gain there... heck, going from standard to AI gets you about 150fps. Furthermore, the VLDs are usually seated into the lands, or very close to them... so the only advantage is not having as much bullet in the case. You think that .25" less bullet can increase case capacity enough to get 150fps... I think not. Increased pressure, twist rate, moly, fast barrel, barrel length, good load... a lot of things could contribute to the extra buck-fifty... but to attribute it to the slightly longer throat would be a real falacy. ~JT

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.25AOD,
I dont mean to flame you on your two posts, but you could not be more wrong if you went out of your way to try.
The longer throat is exactly what gives this round its added velocity.
In my opinion the problem with WSM and SAUM is that the SAAMI spec O.A.L. is very short so your bullet is taking up a great deal of powder capacity, with the chambering that fiftydriver did for me the bullet is not taking up any powder capacity because it is in only the neck. the SAAMI spec O.A.L for a 7WSM is 2.860" the O.A.L. for my chambering is 3.230 making a difference of .370" if you add in bullet diameter of .284" ,that is a lot of powder capacity. I will let some mathematical genius figure out how much.
UB

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As I go back and read the article the chamber that was cut with a +.250" lead OVER SAAMI spec was 116fps SLOWER that the SAAMI spec chamber with 180 grain accubonds!! So, in the Nosler Ballistics Lab... the LONGER THROAT WSM was SLOWER with equal weight bullets. Now that being said... the barrel was 2" shorter(The SAAMI barrel was 26" while the +.250" lead [that's the longer throat] was a 24" barrel), so we can knock-off 60-80 fps, and pressure was slightly lower in the +.250" chamber (although by less than 1k psi). By the numbers in this article I think you would be hard pressed to gain 50fps by shooting a longer throated WSM... let alone 150-200!!
By your line of reasoning it would be easy to duplicate the performance of the .280 AI by simply lengthening the throat of a standard 280 Rem. Is this the case?
To quote Chub Eastman at the end of the article: "Theories and logical reasoning sometimes go down the drain when you actually pull the trigger and RECORD THE RESULTS"
Now for those who have shot the longer throated 7mm WSM and achieved higher than normal velocities... I don't doubt that you did. However, those differences can be attributed to other factors like a longer slick custom barrel, VLD style bullets and such. But, more than likely it's attributed to higher than standard pressure. It's tough to argue with the Ohler Model 83 in a very reputable ballistics lab.
For those interested in the article it is on page 60 of the May 2005 issue of "Rifle" magazine and is titled "3 Inch, .300 WSM". ~JT
 
Hi if using Rem cases fir the REm SAUM and Win CASES for the WSM the velocity of both is almost identical and believe it or not the rem case has a slight advantage as the win cases have thicker walls making them have slightly less capacity. As for the case issue Norma now makes brass for both so their is no advantage there. I like the performance and design of the Rem over the Win design and have one it shoots very well. If you were looking for a wildcat get the Norma WSM cases then full length size them in A Rem SAUM die and have a reamer made this will give you a REm SAUM with a longer neck i am doing just this for a long range F Class rifle with some changes to shoulder angles and shape. I think the extra fee applied to WSP rifles and accesories will now make the Rem SAUM a better proposition as they do not have to pay a fee for the use of the design as i believe AJmmison or another company took the big W to court for patent breaches now all WSM rifles are slamed with a fee for the use of the design. Their are already some companies dropping the WSM cartriges because of this Ruger has already dropped the WSM's and time will tell if they are replaced by Rem SAUM's.

Cheers Bill
Australia
 
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