John MH Posted January 1, 2011 Report Share Posted January 1, 2011 That's pretty impressive velocity John, how long was the case life? Your findings using RL17 will be very interesting. Case life was about 4 reloads before the primer pockets loosened up using reformed Winchester 22-250 cases. Norma cases are still going strong but have only seen 3 reloads so far. Link to comment Share on other sites More sharing options...
brown dog Posted January 1, 2011 Author Report Share Posted January 1, 2011 Fascinating thread! Ian, thanks. That 6AR link was interesting. Not sure that it clarified anything for me , but interesting! John, 2500 6XC cases?! Other than ‘why?!” I don’t think I’d be considering a change if I had a lifetime’s supply of niche brass sitting in a cupboard . Just had another play with the figures to include 308 and also see how things compare at 600 Well, 30BR isn’t the golden bullet that I thought I saw this morning. The more I look at it, the more confusing it is. Shades of grey. On the scale of wind performance, wherever you choose to get onboard; there ain’t much change without big jumps; 308 to 6BR – nothing in it; 308 to 6.5x47 not worth making the change; but 308 to 243/115DTAC –wow! I’m getting the profound impression that (except at the extremes) wind performance has just about chuff all real-world relevance as the basis for a choice. Here’s a chart that’ll probably make no sense to anyone but me; I wondered what percentage wind performance change at 600yds a user of one calibre sees when he looks at one of the others. So, for eg, in the first column a 308 user sees a 6BR user putting on 10% less wind and a 243/115DTAC user putting on 30% less wind. In the 3rd column, the 6.5 user sees only a 6 or 7% wind difference in relation to 6BR or 260. Not worth arguing the toss between them on wind performance Strikes me that in the middle ground; the real decision driver actually turns out to be something other than wind performance: recoil, cost, barrel life, ease of use. That hasn't really got me further; but I'm starting to get the feeling 6BR maybe the ultimate compromise choice when all factors are considered. But if it's just about wind performance; the 115DTAC is a country-mile ahead of everything else. Link to comment Share on other sites More sharing options...
6mmBR Posted January 1, 2011 Report Share Posted January 1, 2011 How about the 6x47 Lapua it will mag feed fine better barrel life than a .243. Will give you 3000 fps with a 115 DTAC and 3100 with 105 bullets. Low recoil as well. Cheers Dave Link to comment Share on other sites More sharing options...
Ronin Posted January 1, 2011 Report Share Posted January 1, 2011 Er,,,,, I have a 243 AI reamer, throated for the D-Tacs...... Don't tell everybody Link to comment Share on other sites More sharing options...
John MH Posted January 1, 2011 Report Share Posted January 1, 2011 Fascinating thread! Ian, thanks. That 6AR link was interesting. Not sure that it clarified anything for me , but interesting! John, 2500 6XC cases?! Other than ‘why?!” I don’t think I’d be considering a change if I had a lifetime’s supply of niche brass sitting in a cupboard . Just had another play with the figures to include 308 and also see how things compare at 600 Well, 30BR isn’t the golden bullet that I thought I saw this morning. The more I look at it, the more confusing it is. Shades of grey. On the scale of wind performance, wherever you choose to get onboard; there ain’t much change without big jumps; 308 to 6BR – nothing in it; 308 to 6.5x47 not worth making the change; but 308 to 243/115DTAC –wow! I’m getting the profound impression that (except at the extremes) wind performance has just about chuff all real-world relevance as the basis for a choice. Here’s a chart that’ll probably make no sense to anyone but me; I wondered what percentage wind performance change at 600yds a user of one calibre sees when he looks at one of the others. So, for eg, in the first column a 308 user sees a 6BR user putting on 10% less wind and a 243/115DTAC user putting on 30% less wind. In the 3rd column, the 6.5 user sees only a 6 or 7% wind difference in relation to 6BR or 260. Not worth arguing the toss between them on wind performance Strikes me that in the middle ground; the real decision driver actually turns out to be something other than wind performance: recoil, cost, barrel life, ease of use. That hasn't really got me further; but I'm starting to get the feeling 6BR maybe the ultimate compromise choice when all factors are considered. But if it's just about wind performance; the 115DTAC is a country-mile ahead of everything else. BD, I had, still have, the first T2k imported into the UK. I got it in 6XC and started off using reformed 22-250 cases but when Norma started making 6XC I decided to get a lifetime supply imported from the US, still working my way through it. Link to comment Share on other sites More sharing options...
oaken Posted January 1, 2011 Report Share Posted January 1, 2011 Brown Dog. Its always good to get advice from more knowledgeable people than myself – that means most people - I will be keeping an open mind – and changing it regularly - especially when presented with an excellent argument for the good old .243 Those are some very interesting figures Scotch_egg. I hear what you are saying about the A-bolt and I appreciate any pointers. The one I am looking at has the latest 2 stage trigger (1.5lb) and the laminate thumbhole stock so that is hopefully going to save some cash. It is interesting what you say about your 7mm08 not feeding well but I plan on 6.5x47 which in its longest oal is shorter than standard .308 so it should feed OK, I think it will go 3 + 1 in chamber, is this correct? In what way would you consider the A-bolt action to be inferior to say an R700 from an accuracy point of view? Building a rifle on a Lawton or Barnard action would blatantly stick a finger up to my entire production/economy approach and all the ethics that go with it…………Not to mention the divorce…… Baldie, http://dsc.discovery...ing-a-turd.html I alrady have a Remington, I just don’t want another, especially a R700’. Rup Link to comment Share on other sites More sharing options...
Elwood Posted January 1, 2011 Report Share Posted January 1, 2011 BD, here's a link from 6BR.com. In this post the cartridge is known as the 6 Super X, but it had to be renamed to 6 SLR as Winchester already use the name Super X for one of their own creations. http://www.accurateshooter.com/forum/index.php/topic,1492628.0.html Link to comment Share on other sites More sharing options...
skany Posted January 1, 2011 Report Share Posted January 1, 2011 Hi matt id go with dave & the 6x47 wich should give you a decent performance/recoil/tube life advantage against the 308 with decent tube life & still feed!it also depends on if you fancy shooting vermin with it to i guess as a scenar in 308 aint a great performer ive heard so your bc of a useable bullet will change dramaticaly!(amax.435 i think!) 155g amax agains 105g 6mm amax is a decent leep for me to 6br but im not feeding from a mag like you need it to! 3100 with a scenar in 6mm would be damnd usefull to id have thougth! cheers Andy Link to comment Share on other sites More sharing options...
brown dog Posted January 1, 2011 Author Report Share Posted January 1, 2011 especially when presented with an excellent argument for the good old .243 Those are some very interesting figures Rup, the 243 argument only works for the very heavy VLDs; and they need fast twist barrels - 1:8 or thereabouts from memory; they won't work in 1:10s . Unless you've actually committed to buying an a-bolt, I think the central message being sent is: Don't do it!! As well as all the valid gunsmithy-reasons from others, I shot with the importer a year or so ago; and he was quite unguardedly Ratner-esque about the marque. I just wouldn't go down that route. Dave, Ian, John, Andy, The 6x47, 6XC, 6SLR, 243 etc I can't distinguish between them. Since they're all pushing the 115 DTAC at 3000-odd, then they must all be nuances/ variations on the same theme - and, on the principle of 'no free lunch in ballistics' -they must all doing about the same in terms of barrel life and recoil. The only recoil differences would surely relate to charge weight and be small (I'm guessing they all fall within 10grs of each other?). I think the key choice one makes if choosing one of them is to accept short barrel life in exchange for stunning performance. Between the 3 of them I can't see that the choice between them can be down to any more than which you fancy the look of (I'd be boring and go for the easiest/cheapest to load for ). The stunning performance argument is pretty attractive though! Andy, 243AI and 115s ?! Chrome lined? Link to comment Share on other sites More sharing options...
John MH Posted January 1, 2011 Report Share Posted January 1, 2011 I knew the 6XC to be a potential barrel burner but at the time I bought it I was able to get Krieger, Schnider, Pacnor and Rock barrels at between $400-$500 already to screw on. I still have six unused tubes sat in the safe and have only shot out one Schnider. Link to comment Share on other sites More sharing options...
Ronin Posted January 1, 2011 Report Share Posted January 1, 2011 Remer only used once and it shot extremely well. You dont have to push em as hard as possible, was thinking of 105 / 107 SMK's at 3k. Not sure if the 243 AI would feed from a mag though. It is certainly on my list of possibles for shorter range F Class, and I intend to barrel the barnard in a 6mm "just to say I tried em" May be an interesting project for the BAT too..... From what I gather the most efficient is the 47 / XC derivatives, in terms of velocity per buck, Cases are expensive though... Link to comment Share on other sites More sharing options...
6mmBR Posted January 1, 2011 Report Share Posted January 1, 2011 Advantages of 6x47 are Lapua brass with the small primer pocket. Charge weights run around 38-39 grains of powder. Case life is excellent I think the small primer pockets resist pressure better and remain in good shape longer than the large pockets. My cases are on 10+ firings and Ian(Elwood) kindly annealed them for me and now they are as good as ever. I have yet to loose a case through splitting. My rifle now has 1200 rnds through it and the Pacnor tube is in fine fettle and good for another 1200rnds. Cheers Dave Link to comment Share on other sites More sharing options...
Elwood Posted January 1, 2011 Report Share Posted January 1, 2011 H20 case capacity for the following 6mm's 6x284 65.3 6mm Rem AI 59.9 Crusader 59.9 243 AI 56.9 6mm CM 55.6 6 SLR 55.0 243 54.8 6XC 50.2 6x47 48.5 Good for barrel life, light recoil, quality of brass and ease of use then the 6XC and 6X47 are both worth considering, both will reliably feed from a magazine and if you are shooting McQueens then they would appear to be ideal. The Crusader, 243AI, 6x284 and 6MM AI are the clear speed kings, quality of brass is good Norma/Lapua/RWS but requires forming except the 6x284, barrel life should be about 1200- 1500 rounds give or take. I think there are issues with mag feeding the 234 AI and 6mm AI. 6mm SLR and CM (competition match) and 243 sit in the middle of the above, good brass but you may have to neck turn Lapua for the SLR, no fire forming for both the 243 or 6 SLR, mild recoil and barrel life of 2000+ rounds? and all three feed from a magazine, and doesn't that SLR having one long sexy neck Link to comment Share on other sites More sharing options...
6mmBR Posted January 2, 2011 Report Share Posted January 2, 2011 You may find this interesting for 6.5x47 and 6x47 Lapua cartridges http://www.6mmhot.com/6mmHOT_Load_Info.html Cheers Dave Link to comment Share on other sites More sharing options...
terryh Posted January 2, 2011 Report Share Posted January 2, 2011 Matt, I'd plump for the 243 fast twist with DTAC's. Brass, dies, mag feeding all tick the box. You do not have to run it 'flat out' to be noticably better than your 308, I'm talking about range noticable rather than calculated paper adavantage. As I said, I came up again this combination about 7 or 8 years ago and it was like a laser compared to the 308. Only down side to these smaller calibres is the small bullet holes make calling shots very difficult e.g. Czech comp. Terry Link to comment Share on other sites More sharing options...
ds1 Posted January 2, 2011 Report Share Posted January 2, 2011 Hi Terry, for the CZ comp the BC advantage with a small call is lost not being able to see the hole in the target - been there and done that with 260 Rem and 6,5x55. The best cal I have used for it was 338 Lapua, - BC and big hole (until a yank complained about it). German SEK were using 300 win mag. David Link to comment Share on other sites More sharing options...
Scotch_egg Posted January 2, 2011 Report Share Posted January 2, 2011 I like the .338 but its just far to expensive to shoot in the real world The 6 SLR appears to be the answer to my long neck .243 and easily made. No fireforming and plenty of brass. Link to comment Share on other sites More sharing options...
The_Dogge Posted January 2, 2011 Report Share Posted January 2, 2011 The 243/115DTAC ballistics look compelling, but I'm not sure 3150ft/s is reliably achievable for that load. It looks like George Gardner was using a 27" barrel, which will have to be custom anyway to stabilise the 115. I don't know how much difference moly makes, but that velocity is very high, I can't reproduce it with an 87gn bare bullet with H414 in a 600mm (23.6") barrel and Norma brass, I suspect the Norma brass is rather soft and Lapua would probably be better. I see Sir-Slots-a-Lot gets rather more speed out of the exact same setup I have, but my cases were well into the ejector hole before I got close to his load. It should still be impressive at, say, 3000ft/s but the advantage may not be quite as large as stated. Link to comment Share on other sites More sharing options...
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