New build which 6mm?

Jas1984$

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So for the past few years I have been shooting more long range and looking at a new build over winter. I have a good amount of 7mm’s and 6.5’s in a bunch of different flavors so I figured why not add a 6mm to the family.
My main question is what 6mm would you go with? I do reload for all of my rifles so far and have a good stock of supply’s besides brass and bullets for anything 6mm. I have tried doing a good bit of research on different rounds including 243, 6mm creed and the 6mmx47. So far I’m liking the 243 and 6mm creed because brass seems fairly easy to get ahold of for both, I have noticed the 6mm br rounds seem to be easy to find brass for but all of those seem a bit confusing to me.
The furthest I will ever shoot is probably 1000-1200yds, most my shooting will be inside of 600yds.
Im open to other options as well if anyone has any info on something that would suit me better.
Thank you in advance for any help
 

OREGUN

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    6BR is nearly unbeatable for ease and accuracy out to at least 600 yds and will easily reach 1200. Dasher or 6 BRA are just as good/maybe better but a little more complicated. 6CM can be bought at any sporting goods store if you don’t want to reload. .243 is an excellent choice but factory offerings aren’t as “precision” focused…more hunting. And it will burn up barrels faster.

    Theres really very little argument against 6BR, in my opinion. Best barrel life of the bunch, dumbass easy to reload, super accurate, good powder choices (although powder is the hardest component to find right now) and it uses the least amount of powder so more loads per pound. After that, my order of preference would go 6BRA, 6CM, 6Dasher, 6x47, .243Win. With 6CM and dasher being interchangeable at the number two spot depending on your passion for factory ammo.
     

    iceng

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    I've had a whole bunch of 6mm's over the last few years. Honestly, it's whatever you can get components for EASILY and readily.

    I hate 6cm.... But it's a solid option. I hate 6br, but if you have access to components (brass and dies) then do it.
     

    CamoWhamo

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    There's also the new kid on the block, the 6mm GT.
    It falls in between the 6mm Dasher and the 6mm x 47 or Creedmoor.

    The pros are that the longer case feeds better than the BR based rounds and doesn't need any special magazine or follower kits to enhance reliability.
    It uses about 3gn more powder than the Dasher. Can push the 109's above 3,000fps if you don't mind shortened brass life. I've found it's happiest around 2,930fps or even on lower node around 2,870fps.

    The cons are that as a new round, until now it's strictly a handloader's proposition. Brass is available from Hornady and Alpha. Dies are slowing rolling out. You can now get them from SAC, Hornady, RCBS, Redding, Wilson and Whidden.
    GAP just announced there will be factory ammo around from Hornady with a new 109 ELD-M bullet coming in Feb of 2022
     
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    MinnesotaMulisha

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    There's also the new kid on the block, the 6mm GT.
    It falls in between the 6mm Dasher and the 6mm x 47 or Creedmoor.

    The pros are that the longer case feeds better than the BR based rounds and doesn't need any special magazine or follower kits to enhance reliability.
    It uses about 3gn more powder than the Dasher. Can push the 109's above 3,000fps if you don't mind shortened brass life. I've found it's happiest around 2,930fps or even on lower node around 2,870fps.

    The cons are that as a new round, until now it's strictly a handloader's proposition. Brass is available from Hornady and Alpha. Dies are slowing rolling out. You can now get them from SAC, Hornady, RCBS, Redding, Wilson and Whidden.
    GAP just announced there will be factory ammo around from Hornady with a new 109 ELD-M bullet coming in Feb of 2022
    Prime is also selling 6GT Ammo, but like everything else, availability is scarce.
     

    rookie7

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    I've had a whole bunch of 6mm's over the last few years. Honestly, it's whatever you can get components for EASILY and readily.

    I hate 6cm.... But it's a solid option. I hate 6br, but if you have access to components (brass and dies) then do it.

    Why do you hate 6 creed and 6br? and since you have had a variety of them which ones do you like?
     

    DJL2

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    I was looking at the Rainbow Tiger recently simply because the data looks like it has powder commonality with the 6.5 Creed (which it would replace on one gun, but I would still load). Factory support is starting to trickle out for it. As was stated, I don’t need to engage in the hassle that the BR case sometimes necessitates. I don’t actually have anything against the 6.5… if I could grind out some better performance from a longer barrel…
     
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    generalzip

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    What’s the gun going to be used for? If you plan to and don’t mind reloading as you’ve stated here’s my take after shooting all these calibers

    Target shooting at steel- 6BR. It is stupid easy to tune. Lapua brass available. Crazy accurate with little to no load development. 28.5-29g h4895 and a 105 berger will shoot 1 hole. This is the easy button. Only downside is mag feeding can be a little finicky but you’ll eventually find/tune a mag that feeds reliably. Great barrel life.

    Hunting rifle/occasional target shooting- 6 creedmoor. I am currently building one. Reliable mag feeding. Enough energy for deer etc out to pretty good distances. Barrel life is fairly short but for hunting it will last a lifetime. Plenty of factory ammo options and lapua brass.

    Don’t let people tell you that you need more powder to reach further. In a PRS match I had the highest score on a stage at 1505 yards with a straight BR… the accuracy and vertical on the BR case is not rivaled by any other 6mm cartridge in my opinion.
     

    Gtscotty

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    There's also the new kid on the block, the 6mm GT.
    It falls in between the 6mm Dasher and the 6mm x 47 or Creedmoor.

    The pros are that the longer case feeds better than the BR based rounds and doesn't need any special magazine or follower kits to enhance reliability.
    It uses about 3gn more powder than the Dasher. Can push the 109's above 3,000fps if you don't mind shortened brass life. I've found it's happiest around 2,930fps or even on lower node around 2,870fps.

    The cons are that as a new round, until now it's strictly a handloader's proposition. Brass is available from Hornady and Alpha. Dies are slowing rolling out. You can now get them from SAC, Hornady, RCBS, Redding, Wilson and Whidden.
    GAP just announced there will be factory ammo around from Hornady with a new 109 ELD-M bullet coming in Feb of 2022
    ^Is this part a joke? If not where can I find the announcement or details?
     

    CK1.0

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    I've spent the better part of a year trying to find a reason to get something more hip/fancy than boring old 6CM... and after having looked hard at all of them... I'm sticking with 6CM.

    Without a stockpile of Varget, IMHO there's really nothing to gain by bothering with any of the smaller 6's. Even with plenty of Varget: mag kits suck, dealing with bougie brass sucks, SRP-only sucks.

    Most of the stuff guys throw around concerning 6CM just isn't true (or was only true 10 years ago when everyone was running it to 3100+fps seated right on the lands): "it's a barrel burner" - nope, "it's tough to load for" - nope.

    Currently I run 41gr of Staball in 6CM for ~2900fps with a 112/115gr bullet, while Dasher would take ~37gr and 6GT maybe ~39gr running a 105/107gr bullet... They all recoil pretty much the same, except I can run a heavier 112/115gr bullet that's slightly better in the wind and with a better BC. Running a healthy jump, barrel-life is the same as any of the smaller 6's.

    (The cheap/easy brass and factory ammo is there too, but I don't even consider that.)
     

    Jas1984$

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    What’s the gun going to be used for? If you plan to and don’t mind reloading as you’ve stated here’s my take after shooting all these calibers

    Target shooting at steel- 6BR. It is stupid easy to tune. Lapua brass available. Crazy accurate with little to no load development. 28.5-29g h4895 and a 105 berger will shoot 1 hole. This is the easy button. Only downside is mag feeding can be a little finicky but you’ll eventually find/tune a mag that feeds reliably. Great barrel life.

    Hunting rifle/occasional target shooting- 6 creedmoor. I am currently building one. Reliable mag feeding. Enough energy for deer etc out to pretty good distances. Barrel life is fairly short but for hunting it will last a lifetime. Plenty of factory ammo options and lapua brass.

    Don’t let people tell you that you need more powder to reach further. In a PRS match I had the highest score on a stage at 1505 yards with a straight BR… the accuracy and vertical on the BR case is not rivaled by any other 6mm cartridge in my opinion.

    Thank you for all the info... the rifle will be used for steel and target shooting and I will definitely be reloading for the new build, I have no interest in shooting factory ammo at all out of this build. From all of the replies on here I’m starting to think the BR might be the path I want to take now. I did consider the gt but brass and dies seem a little harder to come by.
     
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    JustSendit

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    If you’re not competing in something specific, I’d stick with 6CM. Plentiful components, lots of factory ammunition, it’s a cool plus that you can neck down any 1x 6.5, runs a huge variety of bullets well, feeds reliably.

    Reloading 6cm is fairly straightforward so dialing in a .5moa with a low ES on 6cm isn’t too difficult.

    If you’re aiming for competition then I’d steer you towards a BR variant or GT. Now the components are a little harder to find.
     
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    Lunchbox27

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    I have barrels in 6CM and 6BR. The 6BR is by far the easiest to load for and gets you stupid groups. That said.. its tough for me to see hits, let alone movement on a plate with the 6BR past 1,000 yards (105 hybrid @2850fps). Since you are reloading, i say go 6BRA for the extra velocity.
     
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    generalzip

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    I have barrels in 6CM and 6BR. The 6BR is by far the easiest to load for and gets you stupid groups. That said.. its tough for me to see hits, let alone movement on a plate with the 6BR past 1,000 yards (105 hybrid @2850fps). Since you are reloading, i say go 6BRA for the extra velocity.
    I currently shoot BRA. Once all the brass is used up im Going back to straight Br. If you want more velocity get a longer barrel. In a 28” barrel I get over 2900fps in a straight BR without pressure using h4895 and a 105. Fireforming is a massive pain for little/no practical gain.

    If consistency and accuracy out to 900-1000 is what you want get a straight BR. If you want to use alpha brass a dasher works too and splits the difference. I have alpha 6 creed brass (bought before lapua came out). And it’s good brass.

    If you can’t hit a target out to 1000 with BR, you’d very likely miss with the creedmoor as well. 100-200 fps doesn’t make the difference with wind etc as most people think. Knowing your dope perfectly, small groups (confidence in the rifle), low SDs/vertical, and good wind reading is what hits steel at distance.
     

    reubenski

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    I have pretty much all the cartridges listed. Don't have a X47 or BRA. 6CM is the easy button. You can buy once fired brass on the forum. Every large brass manufacturer makes 6CM brass. You can buy it in all primer sizes.

    The cartridge itself is sized well for feeding in the largest vareity of platforms. It offers the largest flexibility in loadings. High-speed explosive 75's and 87's, match oriented 95 to 115's, and round nose hunting 120's. Some of the smaller cartridges would struggle with the latter bullets.


    Get a SAAMI chamber and jump your bullets .100" or more.

    Definitely do not get a 6XC unless you want to play the Gen I vs Gen II game and want to learn about matching chambers and dies in intimate detail.
     
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    generalzip

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    I’d agree with that. If you do most your shooting at 1000 no 6mm would be my recommendation. Go with 6.5 creed or short mag 6.5 or 7mm like 6.5 PRC or 7 saum
     

    reubenski

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    600 yards and in nothing will beat 6mmBR or 6mm Dasher. 1000 and beyond you really have to kick a 6mm in the ass to keep up with the 6.5mm's and up
    In terms of what? Spotting hits? I beat a huge field of guys shooting long actions, 284's, ,6.5PRCs in a match in which half the stages were over 1000 with one stage to a mile. The consistency and Accuracy are BR based cartridges doesn't expire at 1000. That match is where I learned and reinforces up-gunning to magnums doesn't always guarantee more hits.
     

    Darkside-Six

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    I’d say 6GT fits all of those bills. Several good and easily available powders work well. Stupid accurate and stupid easy to load for. No feeding issues. No fire forming. And barrel life is really good. 3k or more. Now we also have GAP and Hornady making factory rounds
     

    JustSendit

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    In terms of what? Spotting hits? I beat a huge field of guys shooting long actions, 284's, ,6.5PRCs in a match in which half the stages were over 1000 with one stage to a mile. The consistency and Accuracy are BR based cartridges doesn't expire at 1000. That match is where I learned and reinforces up-gunning to magnums doesn't always guarantee more hits.
    You won a essentially elr an match with dasher? That must have been a big deal. Surprised I didn’t see more BRs at the NF ELR match this year.
     

    reubenski

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    You won a essentially elr an match with dasher? That must have been a big deal. Surprised I didn’t see more BRs at the NF ELR match this year.
    Q Creek club match a couple of years ago. Second place. Ever shoot it? Since you're a pro now
     
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    I went through this dilemma about a year ago when I was building my first 6mm and settled on a 6BR.

    It is as easy tuned as folks say (almost hard to find a bad load) and it is crazy accurate.

    The feeding issue was a non issue for me with MDT 6BR mags, couple of tweaks to the feed lips (2 minutes with a pair of pliers) and my feeding was smooth as silk. This was on a 90 degree 2 lug Impact action, I have heard that the shorter BR based cartridges can be more temperamental with 60 degree 3 lug actions but I have no personal experience with that - food for thought though depending on your plans.
     

    striped1

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    Rocketmandb

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    I sold my 6 CM when I got my 6 BRA. As a bunch of others have said, it's really easy to tune a load and is crazy consistent when you shoot. Also, 6 BR brass is available.

    It's so easy to hit, it's almost not fun to shoot... almost :)
     

    kthomas

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    I’d say 6GT fits all of those bills. Several good and easily available powders work well. Stupid accurate and stupid easy to load for. No feeding issues. No fire forming. And barrel life is really good. 3k or more. Now we also have GAP and Hornady making factory rounds

    I don't own a GT, but I've heard feeding can still be an issue with 6GT without the aid of BR mags/mag kits.
     

    kthomas

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    So many 6mm's, all do a good job of their intended purposes.

    You need to narrow down your objectives, and your wants and needs in a cartridge.

    - Do you value high barrel life, or do you place optimized ballistics over barrel life?
    - What kind of barrel life do you hope to get?
    - Are you okay with using mag kits/dedicated mags, or want to stick to only AICS pattern mags with no modifications?
    - Are you okay with fireforming? How intensive of a FF process are you okay with?
    - What weight of projectiles do you want to shoot?
    - What velocities would you like to achieve with your intended projectile?
    - Do you want very common chamber specs, or are you planning on picking a chamber optimized for you projectile?
    - What kind of reloading powders do you want to use?

    There's lots to think about, and every 6mm has its nuances.

    I went down this road a couple of years ago, and ended up at 6BRA. I'm personally very happy with that choice, no regrets, and it doesn't leave me wanting to try any other 6mm's. However, its certainly not for everyone, but there's a 6mm for almost any purpose.
     

    SporterII

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    I can only speak to the 243. Easy to tune. My first load. Feeds, no drama. 1200 yds, solid with a good bullet.
    Simple.
    8 twist, 105 Berger and 3000 or so FPS.
     
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    Something I forgot to mention in my previous post, when I was deciding on what caliber I got a bunch of good info from podcasts & videos from top shooters. Two things stuck in my mind.

    1) Your post doesn't mention competition but it doesn't really matter, seeing bullet trace is helpful for any situation and is a great guide for reverse engineering where the issue is on misses. There was / is a trend in competition to move to slower speeds to help with seeing bullet trace. It seems many were using faster calibers and found that they preferred the slower BR based calibers for this reason.

    2) One guy who was running one of the faster calibers (6CM IIRC) found that his barrel was fussy with seating depth and he was constantly "chasing the lands". This was a real problem for him in competition as he found that the barrel erosion over the course of the event would be enough to negatively affect the accuracy so he was moving back to BR based cartridges to avoid this phenomenon.
     
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    Interesting. My 243 is similar to 6 CM. One load for 1500 rds was reliable. Barrel is still pretty good spare.
     

    Cardboard Assassin

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    So many 6mm's, all do a good job of their intended purposes.

    You need to narrow down your objectives, and your wants and needs in a cartridge.

    - Do you value high barrel life, or do you place optimized ballistics over barrel life?
    - What kind of barrel life do you hope to get?
    - Are you okay with using mag kits/dedicated mags, or want to stick to only AICS pattern mags with no modifications?
    - Are you okay with fireforming? How intensive of a FF process are you okay with?
    - What weight of projectiles do you want to shoot?
    - What velocities would you like to achieve with your intended projectile?
    - Do you want very common chamber specs, or are you planning on picking a chamber optimized for you projectile?
    - What kind of reloading powders do you want to use?

    There's lots to think about, and every 6mm has its nuances.

    I went down this road a couple of years ago, and ended up at 6BRA. I'm personally very happy with that choice, no regrets, and it doesn't leave me wanting to try any other 6mm's. However, its certainly not for everyone, but there's a 6mm for almost any purpose.

    This ^^^^^ sums it up pretty good.
     

    Cardboard Assassin

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    Interesting. My 243 is similar to 6 CM. One load for 1500 rds was reliable. Barrel is still pretty good spare.

    Good to know. It seemed extreme to me but stuck in my mind.

    Maybe he had a REALLY fussy barrel or something else was going on in the background which was the actual underlying cause?
     

    reubenski

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    Something I forgot to mention in my previous post, when I was deciding on what caliber I got a bunch of good info from podcasts & videos from top shooters. Two things stuck in my mind.

    1) Your post doesn't mention competition but it doesn't really matter, seeing bullet trace is helpful for any situation and is a great guide for reverse engineering where the issue is on misses. There was / is a trend in competition to move to slower speeds to help with seeing bullet trace. It seems many were using faster calibers and found that they preferred the slower BR based calibers for this reason.

    2) One guy who was running one of the faster calibers (6CM IIRC) found that his barrel was fussy with seating depth and he was constantly "chasing the lands". This was a real problem for him in competition as he found that the barrel erosion over the course of the event would be enough to negatively affect the accuracy so he was moving back to BR based cartridges to avoid this phenomenon.
    The BR based cartridges don't erode lands at an exponentially slower rate to the point where shooters don't have to chase the lands. I think it's more the case that people that get wrapped up around chasing lands are just always going to get wrapped up around chasing the lands.
     
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    kthomas

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    The BR based cartridges don't erode lands at an exponentially slower rate to the point where shooters don't have to chase the lands. I think it's more the case that people that get wrapped up around chasing lands are just always going to get wrapped up around chasing the lands.

    That could be true.

    I've never once have chased lands in my 6BRA. Still at same OAL length ~1,500 rounds later as I was after just breaking the barrel in.

    Shoots every bit as well as it always has.
     

    Darkside-Six

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    I don't own a GT, but I've heard feeding can still be an issue with 6GT without the aid of BR mags/mag kits.
    I’ve seen one person have a feeding issue using an MDT mag. I’ve only used AICS & Accurate mags had have had zero issues. But that’s just me.
     
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    Criver600

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    In terms of what? Spotting hits? I beat a huge field of guys shooting long actions, 284's, ,6.5PRCs in a match in which half the stages were over 1000 with one stage to a mile. The consistency and Accuracy are BR based cartridges doesn't expire at 1000. That match is where I learned and reinforces up-gunning to magnums doesn't always guarantee more hits.
    Yawn...Hahahaha I'll stick with what I said.
    I've won 1000 yard matches with a .308 but it takes some doing:)
     

    Average guy

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    6xc. Seems to be a good balance of BR and creedmoor. Norma and Peterson brass both available for it.
     
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    reubenski

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    6xc. Seems to be a good balance of BR and creedmoor. Norma and Peterson brass both available for it.
    The XC and Creedmoor are more similar than just about any of the 6mms. Loads are within a grain of each other. The only difference is brass availability and the multiple versions of XC reamers out there causing die incompatibility problems.
     
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