6BR

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6BR

Post by headspace » 25 Feb 2017, 8:28 pm

I've had a big rush of blood and getting my Howa 6.5 Creedmoor re-barrelled to 6BR. The barrel will be a 26inch I:10 twist from Allan Swan in Brisbane. The stock is one of Cameron Hatchers Thumbholes and the scope is a Vortex Viper 6-24x40. I already have some Lapua brass Forster dies and a variety of 6mm bullets including 20090gn Berger VLD's. I want this rifle for shooting mainly 200 and 300m so that's the reason for the twist rate. I'm starting off with 2208. I'd be happy to hear any other suggestions.
As far as the 6.5 Creedmoor is concerned it lives again in the form of a Savage LRP that's on the way. I'm hoping to give it a run out to 1,000m.
Cheers,
JD :clap:
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Re: 6BR

Post by Apollo » 26 Feb 2017, 10:15 am

For 200 & 300m plus further I would have gone a 1:8 twist so you can use the heavier bullets and lighter would also perform well. The 1:10 in my view is along the lines of a normal .243W calibre and it falls short of ideal when you use bullets of certain types over 90gr. By that I mean 95gr Berger VLD's need a 1:9 twist to suit the bullet length. 90gr Berger Boat Tail Target are ideal.
You mention "20090gr Berger VLD's" which is a bit confusing, is that 200 x 90gr..??? Then also Berger don't make 90gr VLD's in 6mm.
I have a 1:14 6BR Sako which I use for varminting and a 1:8 6BR Barrel for a Stolle which isn't quite finished yet but was intended specifically for 300m to 500m Target with the 105gr VLD's and AR2208.
So, I'm not much help for your specific quest.
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Re: 6BR

Post by headspace » 27 Feb 2017, 7:37 pm

You're right about the VLD's mate, they are actually 90gnBT Target bullets. I did a lot of research before I went to a 1:10 twist. I don't need or want to shoot this rifle further than 300 or maybe 400. I have a 6.5 Creedmoor for longer distance. So my heaviest bullet I'll be using is 90gn which is ideal for the 1:10twist. My Winchester Featherweight shoots 87gn and 90gn perfectly well. So I'm pretty sure the Swan barrel will do the same, only better.
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Re: 6BR

Post by Chronos » 27 Feb 2017, 8:53 pm

I like the BR, even with 105's it shoots like a .223 in a target weight gun and is easy to tune. I was shooting Berger 105's but repeated supply issues and increasing prices saw me looking for alternatives. I picked up "some" (read a good quantity) of Sierra 107's and fortunately they shot well with the same load. I have some of them moly coated now ready to work up a new load hoping to gain a bit of consistency between cleans.

The thing about the BR is it's designed around a heavy bullet and while I'm sure the prairie dog guys in the states like shooting light bullets out of them as a target cartridge I think they excel with 100gr plus bullets

I have several hundred 95gr VLD hunting but i'm saving them to try in my 6XC which is a 10:1" twist so it may be a complete waste of time and they'll get fed to the 6BR when the 107's run out

Something I'm learning with these projects is when you start out buy enough components to last you the life of the barrel because as sure as eggs when you go to restock your favorite pill won't be available

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Re: 6BR

Post by Apollo » 28 Feb 2017, 7:45 am

The thing with just about any VLD Bullet in a barrel that's just on the lower end of the required twist rate is the length of the VLD rather than it's actual weight. I'm sure I had a very old box of 6mm 95gr Berger VLD's that said 1:10 but the current one's have been re-classified to requiring a 1:9 Twist.

In my case of the last test with my .243W 1:10 Twist Barrel was that the 95gr VLD's were just okay at 200m but didn't group well compared to the 90gr BT's and at 300m the VLD's were all over the place and unstable. Pushing them with less velocity I think would have been even worse but each barrel and calibre is different so they may be okay in certain configurations. All those I tested and used were Moly Coated so the velocity is less than a normal bullet unless the powder load is increased to compensate for the loss however accuracy may decrease as I found with my 6.5x47L untill I increased cartridge pressure by jamming into the lands. Okay for target but a bit risky with a hunting/varmint rig.
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Re: 6BR

Post by headspace » 28 Feb 2017, 1:46 pm

I got the majority of my info from a site called Accurate Shooter, where there is a sub site called 6mmBR.com It's well worth a look. These people have been doing a lot of experimenting with 10 twist barrels and getting good results up to 95gn bullets. There is a school of thought that you need to shoot the 100plus class of bullet regardless of range, but that has been disputed. There seems to be two separate "factions" those who want to go really light and those who want to shoot the heavier bullets. However there is a growing number who don't need the longer bullets for up to 300m shooting. The medium range bullet gives better velocity plus they stabilise well in the 1:10. As I said, I don't plan to shoot the 6BR past 300m because my Creedmoor will have the longer ranges covered.
If it's not wood and blued steel, it's not one of mine
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Re: 6BR

Post by Flyer » 14 Mar 2017, 2:35 am

I've had good luck with Sierra's 95gr Tipped Match King out to 500m in my .243 standard barrel Sako. The barrel is advertised as 1:10, but when I measured it, it was 1:9.75. I'm getting them out at up to 3200fps with 44gr of 2209. 87gr V-max would be my next choice, though I notice Berger now has an 87gr VLD for 1:10 barrels.
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