Long Range 6mm

[impalacustom]

I was bored today and thinking, I want to build a 1000yd 6mm rifle and I was looking at the 6-6.5X47, 6BRK, 243 AI and the I really got the cogs a spinning. Has anyone ever thought about taking a 243WSSM and giving it an 40 degree shoulder or possibly a 25WSSM and necking it down to 6mm and doing a 40 degree shoulder on it?
I have a thought that the brass on the WSSM might be a bit thick on the neck so the neck's would definetly need some turning and work to get the right tension. Would they be too much and burn up the barrels, and kill the throat?
I can't really see a lot of difference between the 6-6.5x47, 6BRK and the 243AI give or take 50-100fps but I would don't have QL or anything so I just compared what little data I could find.
Anyone out there ever do such a thing or afflicted with such thoughts as mine? I would be interested in anyone elses thoughts as well.

 

[Dgd6mm]

I recon you were bored, check out joesr threads on a 6CM. Very accurate caliber with plenty of speed and great barrel life.

 

[JRinCo]

It just so happens that I have a very nice model 70 Winchester Coyote in .243 WSSM. It has a 28' Krieger with a .272 neck. It has less that 200 rounds through it and lots of brass.

I'll make you a deal!

 

[MarkS]

impalacustom
The only problem with the 243WSSM is the brass. I know guys that built them and the 243 WSSM IMP> and could not get them to shoot, They said the brass sucked, they words.

You did not say what you are going to do with the gun. If you are going to shoot 1000yd Brechrest the 6Dasher or 6BRX would be the way to go.

If you are going to hunt the 243AI or 6mmAI would be my choice. They would give more horsepower than the smaller cases.

Mark Schronce

 

[teele1]

I agree with DGD6MM I love my 6CM
joesr is great with sharing info on this cartridge
shoot strait
teele1

 

[SongdogHunter]

The .243BRK would be my first choice then the 6 x 47 Lapua. I can't say enough good things about the 243BRK. I'm quite impressed so far.

SDH

 

[cliffy]

LOOK BACK AT A .243 Winchester! All the bells and whistles of something exotic 6mmwise cannot best a true .243 Winnie Pooh potentcywise. Thirty degree shouldered .243 MOXY cannot be bested afield by a 6mm wannabe. Offer your best velocity reading, so I can show you how I can best it. Its all in the careful handloading realm of real performance downrange. p.s. I've just begun studying monolithic bullet performance, because lead is likely to enter the age of dinosaurs, firepowerwise. cliffy

 

[MT300RUM]

LOOK BACK AT A .243 Winchester! All the bells and whistles of something exotic 6mmwise cannot best a true .243 Winnie Pooh potentcywise. Thirty degree shouldered .243 MOXY cannot be bested afield by a 6mm wannabe. Offer your best velocity reading, so I can show you how I can best it. Its all in the careful handloading realm of real performance downrange. p.s. I've just begun studying monolithic bullet performance, because lead is likely to enter the age of dinosaurs, firepowerwise. cliffy

Yep thats why all the long range matches are won with a box stock .243 whinny poo..

 

[alf]

LOOK BACK AT A .243 Winchester! All the bells and whistles of something exotic 6mmwise cannot best a true .243 Winnie Pooh potentcywise. Thirty degree shouldered .243 MOXY cannot be bested afield by a 6mm wannabe. Offer your best velocity reading, so I can show you how I can best it. Its all in the careful handloading realm of real performance downrange. p.s. I've just begun studying monolithic bullet performance, because lead is likely to enter the age of dinosaurs, firepowerwise. cliffy

Yep thats why all the long range matches are won with a box stock .243 whinny poo..

Then again.......

You'll have to look long and hard to find a 243 at a 1000 yard BENCHREST match.

 

[Rtheurer]

The ole 243 won the Camp Perry Long Range Nationals two years in a row. via John Widden.

Its alot of fun to see John Pound the X ring with 105 Bergers at 1000 yards in 4 person shootoff against 6.5X284's.

RussT

 

[impalacustom]

Thanks for everyone's input it is much appreciated. I just now realized that I put this in the wrong section of the forums.

Mark, I too have heard that since the WSSM are running at much higher pressures that the brass is a real problem to work with, I wasn't sure if anyone ever got something to work out good for them or not though. I also plan on shooting it in 600/1000yd benchrest, I want a rifle that will do it's part if I can do mine.

Telee, no offense to the 6CM but I find that Joe seems to be a bit reclusive about his reamer print or the cartridge dimensions and I don't see anything different about the 6CM over the other 6's except his secrecy, I am sure it is a good chambering but nothing that a 6BRK, 6x47 can't do with slower powder as well.

SDH, I have seen your 6BRK on Saubier and I have to say I am a fan of how it looks. I am waiting for Doug to shoot his 6x47 and hear the reports on it too.

Thank you all for your input I think I have narrowed it down to the 6BRK or the 6x47 for the chambering.

 

[Dgd6mm]

Joe released the reamer dimensions to the public about three months ago,the print is out there. There's more info on this site then most wildcats, not to mention the wins and records.I shoot mine quite well at 1000 yards,as good as anything else in the 6's.

 

[Ackman]

Not 6mm, but......An Idaho friend and his riflebuilder came up with a version of the WSSM. It's necked to 6.5mm with a 40* shoulder blown forward quite a bit, an Ackley-ized 6.5WSSM. A real good looking cartridge and very accurate. He shoots the 142 Sierra at about 3200 or so.

 

[HPMike800]

I looked at the 243BRK and the 6SuperX, same case really. The 6XC dies resize a lot more of the case than the BR die does.

 

[1000yardstare]

Used a stock .243 Savage 12FV in F Class last summer. Wanted more oomph to fight wind gusts at 1000 yards. Got a MacLennon 6AI barrel on a 722 action over the winter. Fajen prone stock, Anschutz fittings, Bushnell 4200 6-24 Tactical scope, Burris Z-rings, Timney trigger. 30 inch barrel launches a 107 MK at 3250 fps using RX22. Very impressed with the 6AI cartridge in long range practise this Summer on the Canadian Army ranges. Noticed a definite ability to resist wind gusts compared to the .243.

The real test will be this weekend at the Ontario Fullbore Championships at Base Borden. F,O) class will be a tough fight. Then the next weekend is the Canadian Fullbore Champs at the Connaught Ranges in Ottawa. More International shooters there. Usually quite a few U.S. entries. Three weeks from now I wil be able to compare the 6AI performance to last year`s .243.

 

[jghoghunter]

I shot a strait 243 win. in the world open at williamsport this year and took 9th in the light gun overall and 6th in the 2 gun overall. So I would say it does ok at long range. 3 shots cost me 1st. place, 1 was my fault the other 2 I'm not sure.

 

[Phil]

How bout a 6mmAI.......

 

[1000yardstare]

phil: Just got back from the Ontario Fullbore Champs on a Canadian Army base where I used a 6AI MacLennon barrel on a Rem action. Used a .243 Savage 12FV last year. Am in the process of comparing the results between the two rifles. Will report same to this thread.

 

[1000yardstare]

Took second place in the F Class Friday Agg,300, 500, 900, 1000) at the 2009 Ontario Fullbore Champs. This year was shooting a 6AI MacLennon 30 inch stainless barrel on a Rem action, Fajen prone stock, 107 MKings, 3250 fps. Last year shot a stock .243 Savage 12FV, 26 inch carbon steel barrel, 107 MKings, 3050 fps. Both rifles equally accurate at 300 metres. As luck would have it, the conditions were identical for both years during the 1000 yard match - 4PM, 5 mph wind 11 o`clock to 5 o`clock, wind flags, visible mirage, blue sky, 20C,68F). So allows a comparison of the results between the two rigs at 1000 yards. Both years shot on the DCRA V-bull target, 1 minute V-ring,inner circle), 2 minute 5 ring,middle circle). Outer circle is the 4 ring. Plots below at 1000 yards show a 48-5V for the .243 on the left and a 50-7V for the 6AI on the right. These results are consistent with practise sessions showing the 6AI more forgiving on wind reading at the long ranges.

 

[bandit10-4]

Don't forget the 6-284...