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The new WSSM in .243 and .223 bores.

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14 January 2003, 06:29
<leo>
The new WSSM in .243 and .223 bores.
Just saw a winchester ad about these new "win. super-short magnums" that are based on a shortened .300 WSM case(1/2 inch shorter). I wonder how well these stubby little critters will feed in a bolt-action? The .243 WSSM is supposed to be faster than the .243 winnie by 200 fps and the .223 WSSM is supposed to out do the .22-250 by 200 fps.
14 January 2003, 06:55
Savage99
I am still interested in the 243 WSSM but a little disapointed that it seems the shoulder angle is going to be 28 degrees and not 35 like the WSM's. As to why it's less of an angle I am not sure.

I like the M70 Classic rifle in that caliber as it's small. The LOP is 13.25, it weighs only 6 lbs and the barrel is 22". This is all just as I wanted except that I think I want SS and a plastic stock.

I would have just ordered one if it had come out in SS. Now I am going to wait and see how it settles out. I have got two "new" rifles coming this winter anyway and one is a Swift so my plate is full.

The Winchester site shows two factory loads for the .243 Win and the 100 gr bullet. One is 3090 fps. The data on the 243 WSSM's 100 gr bullet is 3110 fps I think! In any case I am not a big fan of the .243 case. Maybe the WSSM will be a better one.

www.shortmags.org
14 January 2003, 07:26
Rich Anderson
The 223 WSSM is interesting to me. I was thinking of getting another 22/250 and this might fill the gap just fine. We'll let some dust settel and see how they shake out and what other firearm mfg's chamber these newest offerings.
14 January 2003, 07:28
<bigcountry>
My gosh. There is no limit, is there. I have no problem with them coming out with these rounds. But I always thought the 22-250 cooked the barrel. This thing would be moving like a 22-250 AI. And I know people with those that cooked a barrel in 1200 rounds with those. I am all for more improved rounds coming out. But there is a point where I got to ask myself, is it worth it for the barrel.
14 January 2003, 08:16
<John Lewis>
Savage99 - they probably changed the shoulder angle to aid in the feeding.
14 January 2003, 15:24
Savage99
Yes John and I am the one who said they could feed anything.

Where their necks are really stuck out is the copy that claims it will be everyones favorite bench rest rifle!

There is a article in Precision Shooting on accuracy and shoulder angles. As I recall it 20 degrees and sharper is good and very sharp is no good either as it directs primer energy back and not into the slug of powder that is supposed to be blown into the neck-shoulder junction by the inital primer energy. The author claims that a shoulder with a outside radius is best and he has Norma running tests on it.

I just like the look of the 35 degrees shoulder that's all. The 300 WSM is one of the best looking cases in my opinion.
15 January 2003, 04:10
<John Lewis>
Savage99 - I saw that ad. That's a hoot. I haven't read that article, but it kinda flies in the face of everything we've seen over the years, if I'm reading you correct. I guess everybody should use the Wthby shoulder? By the way, something I was told years ago, do you know why Wthby. originally used the double venturi shoulder? There was only one reamer maker in the country at the time that could grind it and Roy wanted to keep the design proprietary, so a contract was drawn up and voila.
15 January 2003, 04:48
Brad
John L., I believe that... the truth is usually simpler than fiction [Big Grin]

Savage99, I think they made a good move with that 28 deg shoulder... I'm still scratching my head over why they'd saddle rounds like these with 22" bbl's?.?.

BA
15 January 2003, 07:25
<Savage 99>
John Lewis,

The experimental shoulder radius is the opposite of a Weatherby radius that I would call a inside radius. It's to direct the primer energy to one spot where the inventor claims the best ignition will happen.

Brad,

I see more 243's with 22" barrels than any other length. Over on 24hourcampfire Sisk just did a test with various rifles that are similar to the WSSM's in expansion ratio and found that the average velocity change per inch of barrel length is 19 fps!

I had a 26" .243 since 1957 with a medium target barrel. It looked the part of being a long range varminter with it's 15X Unertl Ultra Varmint on it. Now Sisk tells us that I had 80 fps more than a 22" barrel! Since the benchrest shooters go for shorter barrels it makes me wonder.

Anyway if I got a 243 WSSM it would be a carry rifle. I have plently of heavy ones including a 40X in 6MM with a 28" barrel.

[ 01-14-2003, 22:27: Message edited by: Savage 99 ]
15 January 2003, 07:36
Brad
99, I've seen Charlie's data... as most know I'm an advocate with short barrels... to a point. I have a 243 with a 22" bbl... to me that pushes the envelope... not because of velocity loss but because of NOISE... it's damn loud. The WSSM's hold more powder and will be even louder. Funny though, my 300 WSM with its 22" bbl is quieter than my previous 22" bbl'd 270... go figure!

BA
16 January 2003, 14:06
Major Caliber
Brad, the WSM has longer effective barrel length, the case is shorter than the .270 win.
16 January 2003, 17:42
Savage99
Thanks GSF,

And the WSSM is shorter than the 243 so the blast will be ok.

Huh, what did you say?
16 January 2003, 18:45
Brad
GSF, what are you on about?

It's not about how big a case is, it's the relationship between bore volume and case capacity.
17 January 2003, 01:17
Major Caliber
quote:
Originally posted by Brad:
GSF, what are you on about?

It's not about how big a case is, it's the relationship between bore volume and case capacity.

No Brad. Think about it. If you have a 22" barrel, and 2 cartridges, one is 1" long, the other is 2" long, the shorter one has an extra inch of barrel length to burn powder.
17 January 2003, 04:01
Brad
GSF, I'm probably wasting my time responding but...

As a PERCENTAGE of POWDER vs. BORE VOLUME the 243 WSSM has LESS area to burn its smaller powder charge than the larger 300 WSM its powder charge. As a result, using identical powders the 243 WSSM wil be LOUDER... .244" bore vs .308" bore.
17 January 2003, 04:42
Savage99
Brad,

When you mentioned that the 243 WSSM was pushing the envelope due to noise it seems to me that your compared it to the 243 Win.

As GFS pointed out the WSSM's have more bore volume no matter what the barrel length than the longer 243 Win cartridge.
17 January 2003, 07:13
Brad
99, when I get a chance I'll post a nice bore volume/case capacity formula for you so you can understand what I'm saying (unless somehow we're talking about two different things)! The 243 WSSM will probably come out having a bore-volume/case-capacity somewhere around what the 22-250 has... my only point in refrencing the 243 was in pointing out that if it is loud (with LESS case capacity than the 243 WSSM) in a 22" bbl., I'd wager the 243 WSSM will be substantially LOUDER... about like a 22-250 in a 22" bbl. 1/2" of barrel more to burn powder means nothing... it's about getting the muzzle blast away from your ears.

BA
17 January 2003, 07:34
<Savage 99>
I am sure we both appreciate expansion ratios. Both cartridges in any length barrel make quite a crack.

A 26" barrel on a 243 is enough to really damage the ears.

A friend who hunts pheasants where he is getting a lot of shots has an expensive set of hearing aid/ear protection devices. He wore them once while deer hunting and did not again. There is quite a good chance of having one fall out and get lost.

I wish we could use silencers here in the USA.
17 January 2003, 08:40
Major Caliber
quote:
Funny though, my 300 WSM with its 22" bbl is quieter than my previous 22" bbl'd 270... go figure!

Brad, I was talking about this statement.