I took a ballistics App and calculated for 5 MPH crosswind with a 200 FPS difference . At 300 yards the windage difference was about 5/16 of an inch . You are on a way higher level of shooting than I am . Do those figures sound correct ?
6BR vs 6BRAI !
- Thread starter Okumacaptain
- Start date
A lot of people are a lot closer or are into pressure than they think they are, especially with these little 6's.
3,000 fps with a 105+ grain projectile is definitely flirting with high pressures in a BRA, and very much so in a BR...
Seems to be common in the BR disciplines in which you are on the ragged edge of performance. Just make sure you know what you are doing and what the potential consequences are if you are going to flirt this closely to high pressure.
The difference between 2880 and 2980 for a 6mm with .541BC 5MPH Crosswind
300 is .2
600 is .6
1000 is 2 inches.
Jet
Gold $$ Contributor
The BRAI is a better choice since it gives you more options. You can run them at BR velocities with great results or run them easily over 3K fps with no pressure and get great results.
From my experience with 103-105 gr bullets, I've run BRAI loads close to 3050 before seeing pressure. Don't think a straight 6BR will tolerate that even out of the best custom actions.
From my experience with 103-105 gr bullets, I've run BRAI loads close to 3050 before seeing pressure. Don't think a straight 6BR will tolerate that even out of the best custom actions.
Why not say a .050 long BR or maybe a br-dx, for that matter?...I know how Bart feels about a Dasher already, so we won't go into that.
Keep in mind that BRA's hide pressure well, I'm not sure why that is. Even if you don't think you are into pressure at 3050 fps, I would bet you are. Shooting that load in high humidity, rain or very high temps may start to expose that. I've personally shot 105's on a charge ladder at 3100+ fps before I started to see obvious signs of pressure, but I guarantee I was way past the line at that point.
But yes, there's almost no downsides to the BRA over the BR, IMO. Fireforming is stupid simple and I've had amazingly accurate FF loads. You can load it to BR velocities if you want, or you can step on the gas a bit with the new velocity ceiling you get. No need to trim, etc.
I agree with you 100% Bart. I run my 6br with 105amax and IMR4895. 2860fps thru chronograph, changed defaults shows my load is just a little more than 500psi below maximum. QL shows me 1 more 0.1 of a gr. would put me a bit over maximum psi. I'm not going there for several reasons, the best one is I don't need to.
My rifle is a steel banging rig plus I've shot 1 1000 yard f class Match using my bipod to finish 3rd.
Hence why I said ( I find it hard to believe ). 6br and variants will jump up over pressure quickly.
So I was close . As I said you’re quite a few levels ahead of me so .3 I probably won’t see due to my lesser skill level .
Nothing Wrong with the 6BR. It’s a great choice.
Ccrider
Gold $$ Contributor
The difference between shooting under 1 inch. .9 versus shooting 1.5 inches at 600 seems justification alone for the 6bra. You see the (over half inch) reduction regardless of your shooting skill.
I understand but I shoot local match’s mostly for fun . I guess if I was shooting professionally for bucks then it would be different .
Ccrider
Gold $$ Contributor
Be thankful. It does not take “shooting for bucks.” Just a little OCD/anal retentive will get you their.
moondog
Gold $$ Contributor
My home range is at 5000 ft. Raton NM is 7000 ft. It makes a difference fer sure!
THIS !
SHall
Silver $$ Contributor
I started 20 years ago shooting IBS 600 yard BR and some 1000 yard. I started with a straight 6BR and did well. With my LG I really had to stand on it for it to shoot. I Shot a very hot load of R-15 for it to shoot. I was pushing 3000fps with that “fast” barrel. No other powder would shoot that fast to get it to shoot. It was hard on brass. My HG shot a very mild load of R-15 extremely well. If you shot it fast it would definitely start opening up the groups. I had to stay well under 2900 fps for it to shoot well. I have shot every 6BR improved made since then in many matches each. BR-DX. BRBS, BRX, Dasher, 6 Grendle, 6x47 Lapua. Shot many records with the old 6BR’s and a few Dashers. I shot the Dasher for a long time and loved the way they shot. I hated the fireform PITA. I then went back to the 6BR in about 2014 so I would not have to fireform. These new barrel would not shoot in 6BR. I then started experimenting with something that was much easier to fireform than the Dasher so I could get good velosity. I ended up with the 6BR-AI. I could get to 3000fps easy like the Dasher with different powders, not just R-15, and not be real hot and hard on brass. I have now settled probably forever with the 6BRAI.
I say all this to give my opinion on what I have seen over the years. Your particular barrel is the determining factor. Some barrels will not shoot until you drive them as fast as possible, like 3000fps or a tad more. A 6BR may not get you to that velosity without ruining brass. With that barrel you are definitely better off with some type of “Improved BR” to get that velosity, and I don’t care which one you choose. Some barrels shoot there best at say 2850fps. That barrel will shoot great as a 6BR as it will with an Improved BR. I have proved this theory to myself several times by rechambering barrels from 6BR to different Improved BR’s. I could give you many examples, but this is long enough to maybe not bore you. I might add, I have heard for years of these two “ nodes” a barrel will shoot good at. A “slow node” and a “fast mode”. I have never ever seen this to be true in my experience. That may happen on one outing with a barrel testing powder loads. But if you shoot over many different outings, that barrel will show you what “one node “ it will CONSISTENTLY shoot its best at day in, day out.
DISCLAIMER: : If you don’t agree with something I have discussed, that is fine. I am not going to argue with anyone. These are just my opinions and experiences.
I say all this to give my opinion on what I have seen over the years. Your particular barrel is the determining factor. Some barrels will not shoot until you drive them as fast as possible, like 3000fps or a tad more. A 6BR may not get you to that velosity without ruining brass. With that barrel you are definitely better off with some type of “Improved BR” to get that velosity, and I don’t care which one you choose. Some barrels shoot there best at say 2850fps. That barrel will shoot great as a 6BR as it will with an Improved BR. I have proved this theory to myself several times by rechambering barrels from 6BR to different Improved BR’s. I could give you many examples, but this is long enough to maybe not bore you. I might add, I have heard for years of these two “ nodes” a barrel will shoot good at. A “slow node” and a “fast mode”. I have never ever seen this to be true in my experience. That may happen on one outing with a barrel testing powder loads. But if you shoot over many different outings, that barrel will show you what “one node “ it will CONSISTENTLY shoot its best at day in, day out.
DISCLAIMER: : If you don’t agree with something I have discussed, that is fine. I am not going to argue with anyone. These are just my opinions and experiences.
Last edited:
Insight from a “One of The Best there’s ever Been”
AckleymanII
Gold $$ Contributor
Yes, but for a varmint hunter, that extra speed means more pieces parts fly'en on p. dogs!
Alex Wheeler
Site $$ Sponsor
I agree. Some guys, more so the 600yd guys get the low node to work. Not me, let's me down too often. In the BRA 3020 to 3050 works for me and probably most at Deep Creek.
Alex Wheeler
Site $$ Sponsor
It's not about speed. Its about running the node you want with powder that shoots best. You want your 6br over 3000fps? CFE 223 is your powder. I have been over 3200 with it in a BRA. It's shoots too. But it's bitchy in the heat.
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.