6BR build: question chamber dimension

[snowpro440]

+1 what dkhunt14 said .

 

[comagutsa]

i run a .272 no neck turn in my 6BR with .105 freebore for my berger 105gr vlds, loaded lapua round is .269
after talking and reading up on pros and cons , some say turn, some say don't neck turn...
in the end i went with no neck turn because it was a pain in my last gun i did it for (lazy haha), but i know a few blokes with 6BR's and they tried turn and no turn and they didn't see any difference in groups , even read a few articles of bloke who won big comps and they didn't neck turn so lazy me went with no turn haha

the blokes i shot with not doing turn are still getting 1-2" groups at 500m

i'm might skim them one day but no time soon

The record group aggs are 1.6 and 1.7 inches at 600 yards. Maybe these blokes need to come over here and shoot. Matt

Mate I haven't measured them to the mm but with fly shooting you get a score on your group too not just what you score on the target.
10 for a 1 inch group and under
9 for a 1 to 2 inch group
8 for a 2 to 3 inch group
Etc
Haven't seen a 10 yet but seen lots of 9s hence why I say 1-2 inch groups... hell I've even done a 9 score for group. ..measured it at home and it went 1.9 something can't remember of my head

 

[comagutsa]

Have a read boys
http://www.500mflyshooter.com.au/index.cfm/articles-content/fly-records-improving-scores-and-lifting-the-bar-by-michael-bell/

Read the bottom about a 600y shot some blokes did in US. 210 scores under 2inch and 11 under 1inch and that was one comp

 

[dkhunt14]

I also bet that most of them had turned necks. Matt

 

[Killshot]

I think tight chambers and neck turning were mandatory when brass was not as consistent as it now is.

I've shot a no-turn Dasher for three years with much success in F-Class.

A .2704" neck with loaded necks measuring .2685" from a .266 bushing and Lapua brass.
I did two tests, turning the brass, just a skim to clean it up, and found no improvement in SD or grouping.

Perhaps other brass may need it, but the Lapuas don't seem to in my application.

 

[CSM19Z5M]

I just received my first 6MM BR rifle. It's a custom rifle built just for varmint shooting. I had my choice of necks and chose no turn .272 neck. Granted, this is a varmint rifle but after reading the comments in this thread and many others while deciding on what I wanted in my rifle, I still haven't found any evidence that turning the necks helps. There is antidotal evidence but no real testing it seems. I am by no means trying to discount others comments for neck turning. I just can't figure out, with so many people having a strong opinion on the subject, that someone can't provide quantifiable data to support turning the necks. Had there been, I would have opted for a tighter neck chamber but it just seemed to be one more step prepping and reloading instead of shooting. But, as with so many things, if a person believes that something works for them, then they should continue the practice. Confidence in reducing all possible variables is vital to consistency for sure. Thanks for listening.

 

[comagutsa]

just an update on my no neck turn .272 6BR
changed powder from RL15 to 2208 or varget as you call it 30.6gr and changed to 105gr berger hybrids , these were seated .015 off the lands and got 1.865 inch group at 500m/547yards, this was my 2nd group , 1st group was on way to another 1.8 inch group before i pulled the 5th

 

[dantiff2]

I had it both ways on the same gun Let me explain. I had a tight neck 6BR chamber with a reamer print of .270. I had shot that for a few years with great success and regularly shot groups in the 2's@100 and .4-.5's@200. Then Lapua decided to go to the "new" blue box with their cartridge brass. These new brass yielded a loaded neck dia of .2685-.269" which is what I was turning my old brass to anyway. I decided not to clean these new cases up at all and try them out. I couldn't tell a difference at all. These cases shot identical with run-out measuring at .001" or less measured at the ogive. I have since moved on but that was the deciding factor to me. I would see and talk to guys that were running no turn chambers that did zero turning not even clean up of the necks that could out shoot just as many of the guys that were turning necks. Point being. I think todays cases are held to a tight enough standard that this no turn is the new normal for comp shooting. I will never go back. Just my opinion. I am no record holder, just a guy who likes to shoot. Keep in mind, a bad wind call will do more harm than any amount of neck turning or lack there of

Dan

 

[Steve3]

Are you already a good enough shooter that it is going to make a difference. Are you consistently shooting 1/2 MOA or better. Is your handloading skill/equipment already at the point it is going to make a difference. Or are you best served keeping things simple so you will have more range/trigger time. And then next barrel ask this question. This is just how I see things personally.

I would also have this talk with your gunsmith.

 

[gotcha]

Great insight Steve

 

[MS50]

New member here. There are many threads in this category, I chose this one as it seems appropriate for my questions. I am considering a 6mmBR build for use primarily on long range steel. Possibly limited bench shooting. I have researched the tight chamber vs no turn chamber, die selection (off the rack vs custom), etc. I'm starting to think that a Savage 12 BR is more up my alley. I don't want to turn necks if I don't have to. If I go with the Mod12 BR, will I have to commit to using either Norma brass vs Lapua brass to establish consistency? For example, if I send Lapua brass to a die manufacturer, will Norma brass work in that die? If I buy off the rack dies, such as Forster or Redding competition dies, is there any reason to doubt that I can achieve reasonable consistency? I assume Mod12's will accomodate longer bullets, so I would be OK there for shooting steel. I'm may be overthinking this issue. A custom build would be nice in terms of possibilities, but may be unnecessary for my needs. Any feedback will be appreciated.

 

[knguyen]

MS50: before i built this current custom 6BR, my first rifle which got the whole ball rolling was a savage model 12 BR rifle as you are contemplating.
with this rifle, it is a very accurate rifle:
i just worked up loads with varget to 28.3 gr, berger 105 VLD, jammed 0.010 and it shoots really well.
i now have over 900 rounds down the barrel and she still shoots really well.
setup is simple redding competition S bushing die and redding micrometer seater die is all i used,
i did not even turned the blue lapua brass at all and it has been a great rifle.
iam a huge savage fan.
my first 4 matches shooting at 200 and 300 i was blessed to have won all four matches.
you will not go wrong with savage model 12 BR: in the 6 BR round,
she will shoot well for you.

matter of fact, my good friend bought the exact savage model 12 in again 6 BR , and in his first match he won the factory class and beat my custom rifle by one point.
good luck with your purchase.
feel free PM if you have any questions
khanh

 

[MS50]

Thanks knguyen. I will PM you. I don't want a personal seminar, but I'd like to get started in the right direction reloadiing for the 6mmbr. I shoot a Savage 10fp in 308 that is a real shooter. I can hold my own on steel ranges with my reloads. I know that 6mmbr is a different game, and I want to get some basic information about brass and dies to avoid going off in several directions. Thanks, I'll be in touch.

 

[comagutsa]

the redding bushing comp dies and mic seater and no neck turn with lapua brass in my 6BR is still doing me great , got this group the other day wind coming straight at me and to the right a bit and this is after 1100 rounds down the barrel , 30.6gr of varget and 105gr hybrids .015 off lands at 2940fps (sticker fell off the top hole)
these are at 547y or 500m

second pic i stuffed my best group haha.. 1st 3 rounds on the fly were less than .5inch, 4th round to the right was 1.4inch then i was like a kid in a candy store and shot to early without checking my flags or getting in position and pulled the 5th and made it a 2.9inch group .ahhhhhh

 

[BradY]

Damn I watched that bottom group from above being shot. Made my tight neck dasher look like a shotgun. The little 6BR can do the job. I have a new straight 6BR barrel being chambered tomorrow. No turn neck. Im done with turned necks.

 

[comagutsa]

Damn I watched that bottom group from above being shot. Made my tight neck dasher look like a shotgun. The little 6BR can do the job. I have a new straight 6BR barrel being chambered tomorrow. No turn neck. Im done with turned necks.

;D cheers brad , next time mate , will have to come down and give the F class open a run sometime