What 6mm?

williada · Post by **williada** » Mon Aug 04, 2014 11:57 pm

Guys I have a 6mm blank at 32 inches. I have reamers in .243, 6mm Walker, 6br, 6,6.5x47 Ackley, 6mm Shehane. Which way would you go and why? Let us keep barrel life out of the equation. Let us keep wind reading out of the equation.

DannyS · Post by **DannyS** » Tue Aug 05, 2014 7:38 am

What twist rate is it David? The 6br is hard to go past. Just so nice to use.

Cheers
Danny

Tim N · Post by **Tim N** » Tue Aug 05, 2014 8:17 am

Looks like you've tried them all, maybe you could tell us?

saum2 · Post by **saum2** » Tue Aug 05, 2014 8:18 am

If it was me i'd go with .243 if it was 8T. Because, great cartridge, brass easy to source, plenty of speed without to much pressure to get what u want, so case life is great, able to push the 115 & 117 gn prodjies with ease to compete with or better the 6.5x284 and better than any 6.5 x whatever. Ok barrel life is not great but you said not to worry about barrel life.
I love the 6XC with 115gners but if I had a .243 chamber the 115gners they would be going well over 3100 and could use it all the way to 1000yds easy & be very competitive. Recoil very good so not an issue.
The 108gners would be travelling very well.
Just my 2c worth.
Geoff

Cameron Mc · Post by **Cameron Mc** » Tue Aug 05, 2014 8:22 am

Very easy. 6br.
Inherently accurate. Tough, excellent brass.

Cam

pjifl · Post by **pjifl** » Tue Aug 05, 2014 8:34 am

Starting with a 6BR, you can always open it out to a longer case.
A 6BR is a delight to shoot. And it will manage 1000y easily although wind reading has to be spot on.

One trouble with a 6BR is that it is such a forgiving round that the shooter does not have to refine technique.

I have come to the conclusion that it is really worthwhile to consistently shoot a big boomer from rests (or bipod) for a while. It will show you all of your faults. The you can drop back to a smaller round if you want.

Just my 2c worth.

Peter Smith.

RDavies · Post by **RDavies** » Tue Aug 05, 2014 9:21 am

How about you run your 6BR reamer in further to make a BRX?

KHGS · Post by **KHGS** » Tue Aug 05, 2014 10:16 am

pjifl wrote:Starting with a 6BR, you can always open it out to a longer case.
A 6BR is a delight to shoot. And it will manage 1000y easily although wind reading has to be spot on.

One trouble with a 6BR is that it is such a forgiving round that the shooter does not have to refine technique.

I have come to the conclusion that it is really worthwhile to consistently shoot a big boomer from rests (or bipod) for a while. It will show you all of your faults. The you can drop back to a smaller round if you want.

Just my 2c worth.

Peter Smith.

Spot on, I could not agree more!!
Keith H.

williada · Post by **williada** » Tue Aug 05, 2014 11:04 am

Danny, I forgot to mention it was a 1-8 barrel. Tim, I admit I’ve tried a few, but not regularly week on week over a long period to really get to know the peculiarities of each. The issue for me is both brass and bullets that both Geoff and Cam mention. I had in my mind that the Sierra jacket was better and more tolerant being pushed harder as I like upper nodes for consistency. That thinking was a while back now, and the array of projectiles available to us has increased markedly. So I am genuinely interested in other people’s experiences in 6mm as I have specialised in 7.62mm and tried a few bigger calibres in the past.
I think the 6mm is still a contender because they group and handle superbly and most of our ranges are less than 1000 yards and I am over being hammered by big stuff as I get older. I think I can still read wind at the longs and I want to shoot the best I can for fun. To me, the ease of which you can get supplies would be a factor. I like the suggestions of Peter and Rod of taking the chamber out further. That 6br looks like a good starting point. Peter your 2 cents is probably worth a dollar. Thanks Keith.

DaveMc · Post by **DaveMc** » Tue Aug 05, 2014 12:38 pm

I have had a 6BR and a 6BR long (taken to 46mm and a little less capacity than a 6-6.5x47L. Both are good chamberings but I feel something in the middle around the dasher/6BRX is the best all round compromise. I certainly personally wouldn't go outside these parameters but understand the reason people do.

It is hard to consider these rounds without talking about barrel life and wind deflection as these are arguably two of the biggest reasons to choose a cartridge (and always a compromise between the two.) The Dasher of course has a reasonable compromise of both these factors.

But it holds BR accuracy with excellent 100 to 1000 yard elevation whilst pushing velocity up just a little (The bigger cases gain very little over a dasher for a lot of lost barrel life and arguably more finicky to tune). Brass is easy to come by. It is a delight to shoot and has broken many records. In the right hands and in the right conditions basically impossible to beat.

I would buy another reamer

(but any excuse for me really) but if not then yeah sink the reamer in a little further......

DaveMc · Post by **DaveMc** » Tue Aug 05, 2014 12:42 pm

ps a few guys up here chamber in bigger 6mm (they use the 243 AI but my choice would then be the 6-6.5*47 Ackley) and then rechamber to a 6BR after 1000 or so rounds. This way they get the best of both worlds.
a 6BR does not really need a very long barrel to perform and will probably go for thousands more after the chop.

pjifl · Post by **pjifl** » Tue Aug 05, 2014 2:26 pm

I know a few people who have developed eye and shoulder problems so have fallen back to exclusively shooting the stock standard 6BR. In a 10 Kg rifle it is just so docile.

You have to ask yourself if keeping it standard is a plus. For some people it simplifies matters a lot while other like to dabble. But, don't be afraid of using a standard 6 BR at 1000 y. And it's fun to beat the bigger boys with a toy gun ........

williada · Post by **williada** » Tue Aug 05, 2014 3:25 pm

DaveMc, I bought the Ackley 6-6.5X47 after speaking to Dave Kiff early 2008 and he called it a Long Dasher and marked the reamer as such, but it was yet to be proven. I had it customised with a 40 degree Ackley shoulder at that time because I knew it was hotter than the Dasher. The reason I did this was to reduce the brass flow in a hotter round, and I knew that the Ackley shoulder had a pretty efficient gas flow in terms of turbulence. I also know that reducing brass flow gives better volume consistency.

I was thinking so far so good. If they are still finicky to tune, it would more than likely be an ignition problem in relation to the basic powder column. How would a small magnum primer light her up? If someone has done this it would save breaking out the Pressure Trace.

On the other hand, Brad if you are reading, the case for a straight Dasher looks compelling.

What I will do, is use the gear I have, and unfortunately it’s not a standard Dasher and try the 6-6.5x47 Ackley and do as Dave suggests and cut it back after a thousand rounds and re-chamber to a 6br. Peter, I like the fun idea of using a toy at the longs to scare a few on the odd occasion. David.

Brad Y · Post by **Brad Y** » Tue Aug 05, 2014 4:38 pm

David- like I said the dasher reamer is here if you wish to borrow it. I really think it is the benchmark of 6mm's. Quick on here just did a 6x47L improved with 40 degree shoulder- indeed a "long dasher" and is probably at the range as I type shooting it at 300m to work a load up.

I often struggled at short range shooting in the past, but having the dasher in the arsenal has really increased my 60's at short range and has also put my X count way up where it should be. Will be using it over the short ranges at a DRA shoot this weekend and if its calm will take it further back as well.

Cameron Mc · Post by **Cameron Mc** » Tue Aug 05, 2014 4:40 pm

A cartridge I am running at present is the 6x47 Swiss Match. It has performed really well for me. The only reason I went to this cartridge was because I lucked onto some new brass. This RUAG brass is the best I have ever used. The down side it is very hard to come by.
I run Copperhead 103g with 34g of 2208 for 3100fps. This is just for interest as brass is the issue regarding supply. In saying that it can be formed from 6xc brass.

Cam