.243WSSM? 25WSSM?

[Muddyboots]

Anybody have one and in comparison to old .243Win? Pro's? Con's?

25WSSM is getting my attention to so same questions?

I have a 300WSM 700SA that thinking would be great for this cartridge with Hammers plus have 2.95 max COAL which is a lot extra for longer bullets.

 

[quarterman]

I ve had a 243 wssm and a 25 wssm. I prefer 25 caliber as a hunting round. The 243 wssm obviously had an edge over the 243 win at the cost of barrel life. I personally would take the 243 wssm over a 243 win. I would also take the 25 wssm over both of the 243's. I like the extra bullet weight availabe for the 25 caliber. just my two bits

 

[Mikecr]

The 243win is already a barrel burner. In WSSM capacity, it would only get worse there. Winchester should not have dropped below 25cal with the WSSM line.

25 & 26 (wildcat) WSSMs are excellent, provided using an action designed for magnum diameter cartridges.

 

[Andrew Massi]

They fed terribly and had no practical advantage over a 243 Winchester. They actually had less case capacity than the 243 but higher pressure netted the wssm an inconsequential velocity advantages(60 fps adding 11 yards to maximum upset distance)
If you wanted a 257 short mag just use the 270wsm or 6.5 saum(better brass options) case with your magnum bolt face or maybe even a 257 prc would get you to whatever velocity window your looking for.
The wssm are perhaps the most ridiculous invention in gun development

 

[Muddyboots]

The 6.5SAUM is definitely in the mix and its not a CM. I am all done with the 300 WSM now that my .270TH is cooking so well. The 700SA has somewhat limited COAL so looking at options. Besides I have a 300WM Sendero that shoots lights out for .30 cal stuff.

 

[Mikecr]

The 243wssm is 5gr more H20 capacity than a 243win.
And there is also a lot more to wssm design & build than mere muzzle velocities.
For example, the wssm case is twice as thick as everything else, because Win apparently forms WSSM from cut down WSM.
If you plan on running high pressures, which could be a solid plan, the wssm case should be a consideration on thickness alone.
That's one example, but there are other wssm attributes significant to those looking for them(like efficiency).

 

[Andrew Massi]

The 243wssm is 5gr more H20 capacity than a 243win.
And there is also a lot more to wssm design & build than mere muzzle velocities.
For example, the wssm case is twice as thick as everything else, because Win apparently forms WSSM from cut down WSM.
If you plan on running high pressures, which could be a solid plan, the wssm case should be a consideration on thickness alone.
That's one example, but there are other wssm attributes significant to those looking for them(like efficiency).

Explain how making it out of wsm cases (they dont, companies the size of winchester dont make brass by shortening existing cartridges, cutting into supply and bottom line) would make it twice as thick. Further nosler and hornady list the usable capacity of both at 49.5gr wssm and 50 gr win.

 

[Zen Archery]

Wider variety in .257 cal bullets over .243 with Hammer Bullets.

 

[Mikecr]

Explain how making it out of wsm cases (they dont, companies the size of winchester dont make brass by shortening existing cartridges, cutting into supply and bottom line) would make it twice as thick. Further nosler and hornady list the usable capacity of both at 49.5gr wssm and 50 gr win.

I'll suggest that Hornady is wrong, and hope it doesn't hurt your feelings.

On thickness, WSSM necks are 24thou thick in 24cal!
They're 22thou in 25cal, and necked up to 26cal I get 19.5thou.
I know of no other brass with necks so thick. Do you?

The only way this makes sense, and it totally does, is if Winchester is cutting down WSM cases prior to shoulder/neck forming of WSSM cases. This would put WSM body thickness in WSSM necks, and the numbers match.

 

[Mikecr]

About that neck thickness I should add that you can't expect serious precision from necks so thick.
And before you say to yourself 'no problem, I'll just turn the necks', prepare yourself for what it takes to do it.
Unless you have one of them fancy IDOD turning lathes, you'll find it a challenge. Normal turning equipment, with normal expansion/turning mandrels, are not ideal for necks with this kind of spring back.

A lot of people, including competitors who have built around the WSSM, have failed to reach good result.
Their failures are not the fault of the WSSM, but of their lack of planning.
They did not account for sufficient barrel steel around a magnum diameter case. For needed breech support, for proper feeding, for ejection, for neck thickness. They didn't purchase Win reloading brass and measure it up front -before filling out a reamer print and having proper chamber and dies cut.
And if you want to go with something in WSSM, get an action designed for it. I would suggest Savage.

It's not all bad. I built a 26WSSM IMP with a custom BAT magnum action.
I could have gone 260AI (matching capacity), but I wanted to explore WSSM, and fitted chambering.
It turned out fantastic, and I learned a lot that I could not have otherwise.