6mmx47 Lap Versus .243 Win

pc3

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May 26, 2008
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What is the general consesnus on these two rounds. No doubt the .243 Win has a greater following. Wondering what are the advanatges for an against both rounds, and what lead you to your choice.

Will the 6mmx47 Lap soon have correctlt head stamped brass ?

cheers pc3
 
Re: 6mmx47 Lap Versus .243 Win

no the 6x47 is made from the 6.5x47 Lapua brass. You neck it down and so will not be correctly head stamped.

The 6x47 is small rifle primer, the 243 large rifle primer. You will shoot less powder in 6x47 than 243, but will not stretch cases like 243.

I own and shoot both. Love the 6x47 for the fact that I built a fast twist 7.5 for the heavy bullets. Which, you can do the same for the 243.

Both can run Lapua brass... both can shoot heavy higher BC bullets...

So... it is a toss up. Flip a coin as they are both excellent rounds !
 
Re: 6mmx47 Lap Versus .243 Win

FWIW, I've seen 6x47 stamped brass though it was 6x47 Swiss match.

Funny how times change... I have a reloading book that shows loads for a 6x47. The picture and description are of a 222 rem mag necked up to 6mm, Sierra book as I recall.
 
Re: 6mmx47 Lap Versus .243 Win

If you use 6x47 Swiss brass you then use large primers correct? Does accuracy suffer as a result? I assume no other diff in the case between 6x47 Swiss and the lap case other than primer size?
 
Re: 6mmx47 Lap Versus .243 Win

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pc3</div><div class="ubbcode-body">If you use 6x47 Swiss brass you then use large primers correct? Does accuracy suffer as a result? I assume no other diff in the case between 6x47 Swiss and the lap case other than primer size? </div></div>

The 6X47 he was talking about is based off of a 222 mag necked up to 6mm...totally different beast from the 6.5X47L brass which can be necked to 6mm.
 
Re: 6mmx47 Lap Versus .243 Win

I think Lapua based their 6.5x47 off of the original 6x47 Swiss Match (which was a 222REM Mag necked up). The Lapua is small primer pocket and 6x47Swiss is large primer pocket. I'm sure there are other minor differences but for all intensive purposes, they are part of the same family. My apologies if I'm mistaken.

 
Re: 6mmx47 Lap Versus .243 Win

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Engine22</div><div class="ubbcode-body">What are your intentions for the rifle? That could have some bearing on responses.
</div></div>

It will be for Varminting I run a 6.5x47 Lap now and love it, also want a 6mm of some description.........it's out of these two. I did onw a .243 win on a sako 75 with McMillan A5 and liked the caliber, especially perfromance of 87gr V-Maxes....I'd set this up for 105's however.
 
Re: 6mmx47 Lap Versus .243 Win

If ya really want a 6mm, ck out GAPS 6mm crusader

Feeds from MAG on short action

real close or same as 244 mashburn

should be ideal for what your looking to do
 
Re: 6mmx47 Lap Versus .243 Win

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pc3</div><div class="ubbcode-body">Is the 6mmx47lap better for seating pills out in the aics mags than the .243 ? Or is mag length not an issue with .243 ? </div></div>

The 6x47L can handle much higher pressures and yes you can seat bullets out of the neck shoulder junction while being a little less than mag length in AI mags.There's no problem with 243's at the same OAL.The bullet just goes down into the powder column a little.

For curiosities sake,with my 6x47L,I ran some 105 Bergers/R-17 up in .2 grain increments until the bolt got sticky.That last shot was 3345FPS !!!.The same piece of brass holds a primer just fine.

Steve
 
Re: 6mmx47 Lap Versus .243 Win

AI is dead on the money. I don't know why the 6BR isn't more popular than it is. Its inherent accuracy, low recoil, combined with extreme efficiency and availability of high BC bullets make for a winning combination.

You are talking about 30 grains of powder, 33 tops, pushing a 105 2800-2900FPS. They don't heat up barrels as fast as the other 243/6mm rounds because they burn much less powder. Another plus, especially for varminters is the extend barrel life-nearly 3k rounds.

I know a hold up for some guys was that the case dimensions were not real conducive to magazine feeding. Everyone knows sharp shoulders, minimal body taper, and the short stubby cases just do not feed well. However, in a BDL or ADL configuration, they feed fine, if you use 223 bottom metal with a trimmed 308 follower.

With the quality coming out of Lapua 6BR brass, there is no reason to even run a tight neck anymore or even turn necks at all. IIRC, the current IBS 600 yard world record group was set with a 6BR. I believe it was a 5 shot, .860 group.
 
Re: 6mmx47 Lap Versus .243 Win

As usual Steve123 is on the money. The other advantage is the shorter barrel needed to burn that powder out of the more better 6 X 47. I have run them down to 20 inches still able to hit 3150 with no problems or pressure. Just a 100 fps loss from the same load in a 24 inch barrel. Not to mention mag feeding ease. I wouldn't consider any other 6mm for feeding from a mag or efficiency.

Jason
 
Re: 6mmx47 Lap Versus .243 Win

Another option you might look into is the 6XC....very similar to the 6x47 except it uses large rifle primers. With a fast twist you can shoot the 105,107,115,etc. with fantastic results.
Barrel life will be on par with the 6x47.

Here is some info on it: http://www.6mmbr.com/6XC.html

If forced to choose between the 6x47 or .243 I would choose the .243 just because I am set up for it now.

Take care,Stan
 
Re: 6mmx47 Lap Versus .243 Win

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: blue_ridge</div><div class="ubbcode-body">I think Lapua based their 6.5x47 off of the original 6x47 Swiss Match (which was a 222REM Mag necked up).
</div></div>

The 6x47 swiss match was a completely different design intended for 300meter prone competition. It has a .308 where the 222mag has a .223 bolt face. The 6x47lapua is very close to the swiss match but it is slightly different where you might have problems loading it for a 6x47lapua chamber.
 
Re: 6mmx47 Lap Versus .243 Win

Holy cow this got F-ed up. I was referring to an old loading book that showed a 6x47 as being a 222 rem mag necked up to 6mm. This cartridge would have a 223 bolt face and nearly be identical to the 6x45 we know today (which is a 223 necked up to 6mm).

The current mention of a 6x47 is a 6.5x47 Lapua case necked down to 6mm and has a 308 bolt face. Hope that clears things up.

And to add a wrench into this... have you looked at a 6xc? 22-250 necked up to 6mm and improved, puts the body/boat junction of a heavy 6mm bullet at the neck/shoulder junction inside of standard mag length of 2.8". Just another thought. It now has correctly stamped brass. have fun.
 
Re: 6mmx47 Lap Versus .243 Win

It sounds like 6x47 Lap is the choice for me if I go ahead with this. Looking to go for a short barrel of around 20" so it seems like the choice for me.
 
Re: 6mmx47 Lap Versus .243 Win

I love my 6x47L, but do not run it nearly as shot as Steve. I have it set up for Berger 108s, and is seated above teh shoulder neck junction with no intrusion into teh base case. Even so, it still feeds just fire from an AI magazine.

Sweet little rig. I built it to use in 600 yard F-Class and steel target plinking, to save wear and tear on my 7WSM.

JeffVN
 
Re: 6mmx47 Lap Versus .243 Win

Jedi

Robert does lots of nice work. If you get a chance to talk with him direct, he is a hell of a nice guy and will answer your questions with no problem.

My 6x47L is based on his reamer.

HE also has some nice 6.5 Grnedel based rigs in .22 and 6mm.

JeffVN