.243 WSSM

[Curious]

Guys,

Looking at the SAAMI specs for this chamber I see the FB is 0.157" which is huge, is anyone running shorter?

I doubt here are any 6mm bullets that would come close to the lands, I appreciate you dont need to be close to the lands for great accuracy but as usual Im curious as to why the FB is so big and if anyone is running shorter?

 

[Ackman]

Guys,

Looking at the SAAMI specs for this chamber I see the FB is 0.157" which is huge, is anyone running shorter?

I doubt here are any 6mm bullets that would come close to the lands, I appreciate you dont need to be close to the lands for great accuracy but as usual Im curious as to why the FB is so big and if anyone is running shorter?

What I don't understand is why they made the neck on those cases so ridiculously thick.

 

[WIB3]

The case is too large for the bullet diameter. Limits your choice for powder. Barrel life is minuscule. Go with a straight.243. You are not gaining anything.

 

[Terry]

I had two of these, a Browning A-Bolt, And a Winchester Coyote. I had no problems reaching the lands.

 

[1lessdog]

The 243 WSSM sure works nice in the AR-15 platform.

 

[mensajd]

The 243 WSSM sure works nice in the AR-15 platform.

Sierra 95gr tmk fit in mag length and are supersonic past 1k. And you can single load even higher bc berger bullets. Hell of a varmint gun.

 

[McFred]

Curious, looking at the SAAMI chamber drawing the .243 WSSM virtually has no freebore. It's just a 1.5˚ leade straight from the case mouth. You should have zero issue reaching lands with any projectile.

What I don't understand is why they made the neck on those cases so ridiculously thick.

They were considerate enough to leave you plenty of material to turn down so you can spec whatever neck wall thickness you desire.

The case is too large for the bullet diameter. Limits your choice for powder. Barrel life is minuscule. Go with a straight.243. You are not gaining anything.

What's a "miniscule" barrel life? Sounds like the ignorant rhetoric parroted by people without experience for the last two decades. No, it's not a 6mm BR and it was never intended to be. The .243 WSSM's virtually the same as a .243 Ackley Improved. If people desire a .243 AI chamber, then there's a reason for the .243 WSSM.

As for powders, you can run anything from BL-C(2) to H1000 in that case. There's nearly 2 dozen powders listed for load data from Hodgdon alone. To which "limitation" were you refering to?

 

[D Ervin]

The 243 WSSM sure works nice in the AR-15 platform.

Sierra 95gr tmk fit in mag length and are supersonic past 1k. And you can single load even higher bc berger bullets. Hell of a varmint gun.

Who built your upper I had one built have sent back2 time still not having any luck with it

 

[Kurz]

Curious, looking at the SAAMI chamber drawing the .243 WSSM virtually has no freebore. It's just a 1.5˚ leade straight from the case mouth. You should have zero issue reaching lands with any projectile.
View attachment 1212223



They were considerate enough to leave you plenty of material to turn down so you can spec whatever neck wall thickness you desire.



What's a "miniscule" barrel life? Sounds like the ignorant rhetoric parroted by people without experience for the last two decades. No, it's not a 6mm BR and it was never intended to be. The .243 WSSM's virtually the same as a .243 Ackley Improved. If people desire a .243 AI chamber, then there's a reason for the .243 WSSM.

As for powders, you can run anything from BL-C(2) to H1000 in that case. There's nearly 2 dozen powders listed for load data from Hodgdon alone. To which "limitation" were you refering to?

If you take a look at the dimension line right behind the throat angle (1.860”) then subtract the dimension right in front of the transition angle (1.7013”) you get the free bore length (0.1587”).

I reach the lands with any of the longer, heavier bullets since that’s what I shoot.

My barrel life has been perfectly acceptable based on my shooting experience.

 

[McFred]

Going by the drawing above (a screen capture of the SAAMI .PDF) from the end of the chamber's ø.2453" dimension it only references a 1.5˚ taper. There's no spec for a ~parallel freebore before the taper, just a 3˚ included funnel. Compare to the .243 Winchester chamber drawing one page up in the same .PDF.

The chamber's transition from ø.2453" to a .237"/.243" land/groove barrel will net you a .0439" "freebore" where a projectile ogive would intersect a ø.2430" groove diameter. I believe what you're refering to "freebore" is actually 0.1585" where the leade taper intersects a nominal ø.237" bore diameter.



I could be misinterpreting something though. Either way, there should be zero issues reaching the lands with even the lightest projectiles in a SAAMI chamber. After 1000 rounds, though, enough steel could evaporate that the lands would indeed be difficult to find at all.

 

[mikecr]

What I don't understand is why they made the neck on those cases so ridiculously thick.

The entire WSSM case matches WSM thickness as you measure up the case -from web.
I believe they merely form WSSM cases from WSM cases. This, leaving thick WSM body brass, also necked down, in WSSM necks.

For anyone installing a barrel chambered in WSSM, you really should plan for turning necks from the 20thou+ down to the 12-13thou range. Ensure the reamer accounts for this.

 

[mensajd]

Who built your upper I had one built have sent back2 time still not having any luck with it

Mike Milli of dtechuppers.com built mine. Shoots and feeds great! http://www.dtechuppers.com/ar-15-wssm-upper-receivers.html

 

[D Ervin]

Mike Milli of dtechuppers.com built mine. Shoots and feeds great! http://www.dtechuppers.com/ar-15-wssm-upper-receivers.html

He built mine and one for a buddy neither will function and customer service is worthless, wont answer phone

 

[mensajd]

He built mine and one for a buddy neither will function and customer service is worthless, wont answer phone

Interesting data point. He’s been building these things for ages. I also had him build me a 20P upper and it functions fine and shoots great - as in 5x5 shot sub-moa on a single target.

 

[D Ervin]

Interesting data point. He’s been building these things for ages. I also had him build me a 20P upper and it functions fine and shoots great - as in 5x5 shot sub-moa on a single target.

Second barrel shots great, Sticking brass, Broke 4 extractors all communication has stopped.

 

[WIB3]

Curious, looking at the SAAMI chamber drawing the .243 WSSM virtually has no freebore. It's just a 1.5˚ leade straight from the case mouth. You should have zero issue reaching lands with any projectile.
View attachment 1212223



They were considerate enough to leave you plenty of material to turn down so you can spec whatever neck wall thickness you desire.



What's a "miniscule" barrel life? Sounds like the ignorant rhetoric parroted by people without experience for the last two decades. No, it's not a 6mm BR and it was never intended to be. The .243 WSSM's virtually the same as a .243 Ackley Improved. If people desire a .243 AI chamber, then there's a reason for the .243 WSSM.

As for powders, you can run anything from BL-C(2) to H1000 in that case. There's nearly 2 dozen powders listed for load data from Hodgdon alone. To which "limitation" were you refering to?

Shoot your .223 WSSM at 1000yds and let me know how you make out. Been there done that. Us ignorant people were smart enough to spend our moldy money elsewhere. Take some advice, neck it up to either 6.5, 7mm or even .30. Than the only problem is obtaining quality brass which doesn’t exist.

 

[WIB3]

I might be just plain stupid, but doesn’t Lapua make.243 brass. I dont see where added velocity gives any known advantages in either hunting or target applications.

 

[McFred]

Shoot your .223 WSSM at 1000yds and let me know how you make out. Been there done that. Us ignorant people were smart enough to spend our moldy money elsewhere. Take some advice, neck it up to either 6.5, 7mm or even .30. Than the only problem is obtaining quality brass which doesn’t exist.

Hey, I tried your suggestion, I tried to shoot my .223 WSSM at 1000 yards, not that it has anything to do with this thread. I had fun anyway. The best I could manage is 965 yards since the Plague has all the ranges closed. Shot prone off bipod and rear bag.

Here's 525 yards (.59MOA) 12" x 12" target:

And here's 965 yards (.77MOA) all 5 in the "ten ring". Target's roughly 15" x 19"

Shooting position:

IMO, that's not bad for SAMMI-spec .22 cal cartridge that was never intended to be shot at ~1000 yards, shot by a rank amateur, using 'cheap' components, who 'smiths his own guns in his garage with cut-rate parts. Imagine what a seasoned benchrest shooter could accomplish with 'premium' componets with a rifle plumbed together by a real actual gunsmith who knows what they're doing! Too bad the WSSMs all suck though, and it's an exercise in futility.

Build/load sheet:
$200 Remington action
$150 Jewell trigger
$155 Wilson SS light varmint barrel
$140 Manson SAAMI reamer (chambered it in my garage)
$150 Boyds stock (bedded in my garage)
$20 Chinrese bipod

37¢ WSSM Fed Brass (garbage, I know)
.265" neck (.275" is the chamber's neck)
19¢ Hornady 88 ELD (crap BC)
12¢ H4350 (37gr)
2¢ Remington 9.5

Have a nice weekend everyone!

 

[Evan]

Hey, I tried your suggestion, I tried to shoot my .223 WSSM at 1000 yards, not that it has anything to do with this thread. I had fun anyway. The best I could manage is 965 yards since the Plague has all the ranges closed. Shot prone off bipod and rear bag.

Here's 525 yards (.59MOA) 12" x 12" target:

And here's 965 yards (.77MOA) all 5 in the "ten ring". Target's roughly 15" x 19"

Shooting position:

IMO, that's not bad for SAMMI-spec .22 cal cartridge that was never intended to be shot at ~1000 yards, shot by a rank amateur, using 'cheap' components, who 'smiths his own guns in his garage with cut-rate parts. Imagine what a seasoned benchrest shooter could accomplish with 'premium' componets with a rifle plumbed together by a real actual gunsmith who knows what they're doing! Too bad the WSSMs all suck though, and it's an exercise in futility.

Build/load sheet:
$200 Remington action
$150 Jewell trigger
$155 Wilson SS light varmint barrel
$140 Manson SAAMI reamer (chambered it in my garage)
$150 Boyds stock (bedded in my garage)
$20 Chinrese bipod

37¢ WSSM Fed Brass (garbage, I know)
.265" neck (.275" is the chamber's neck)
19¢ Hornady 88 ELD (crap BC)
12¢ H4350 (37gr)
2¢ Remington 9.5

Have a nice weekend everyone!

Those are great results!

The smallest groups I've ever shot were with the 88ELD in my 22BR. All right around 0.375" at 300 yards. Definitely a very accurate and consistent bullet. Now if only I could shoot more than 5 in a row without having them start to go poof!

 

[mensajd]

Second barrel shots great, Sticking brass, Broke 4 extractors all communication has stopped.

Sorry to hear it. They're apparently in COVID 19 quarantine right now, so they'll be even harder to get a hold of. Best of luck in getting your issues resolved.