optimal barrel length

[6BRA]

My barrel lengths listed here in an earlier post, from 16" to 29" ALL have the same accuracy potential from 200 to 600 yards, and again from 600 to 1,000 yards, and all 6mm B-R barrels will shoot well under 2" @ 600 yards, regardless of barrel length. I will also point out that this is from "hunting" guns, not B-R, Match or Competition guns.

Curious as to your powder choice on these barrel lengths?

 

[kris bassett]

You had better think about what powder will get you 100 percent burn. Limitations...
Powder burn dictates BBL length IMO.

I ran some numbers in quick load. I used an 18 inch barrel, 87gr v-max, 33.7gr viht n540. It says 2891fps with a 99.8% burn rate.

65gr v-max, 28.9gr 4198, 3195fps, 98.58% burn. Bump it up to 20" and it goes to 3272fps 99.05% burn

 

[BRGUY]

Curious as to your powder choice on these barrel lengths?

I use H-322 in all barrel lengths in my 6mm B-R's.

I tested 3 other powders, and while they provided outstanding accuracy, extreme spread, velocity and best accuracy was not as good as H-322, so that is the powder I am staying with.

 

[rickhirsch]

my last 6bra barrel was 29 inch's and it was Medicor had a little vertical cut it off and rechambered it to
26and 3/4's and it was the best barrel I've ever owned . there's a reason short benchrest guy use 23 inch
barrels . all that. I'm in the process of chambering a new Kreiger its 30. inch's long I'm going to chamber
it to 28. inch's i can rechamber later . 29 to 26.75 i lost 80 fps. that barrel produce's 6 groups at or under
1 inch at 600yds . the only problem i got the new Krieger 6mm has a .236 ?

 

[6BRA]

I ran some numbers in quick load. I used an 18 inch barrel, 87gr v-max, 33.7gr viht n540. It says 2891fps with a 99.8% burn rate.

65gr v-max, 28.9gr 4198, 3195fps, 98.58% burn. Bump it up to 20" and it goes to 3272fps 99.05% burn

Reloading Powders | Gun Powders for rifle, handgun and shotgun | Handloading - Vihtavuori

Vihtavuori premium smokeless powders come in three different series: the N100 single base series and N500 high energy series for rifle and N300 for pistol.

www.vihtavuori.com

5 series VV powder
Pretty sure H322 is Double Base as well.

 

[Ccrider]

and all 6mm B-R barrels will shoot well under 2" @ 600 yards, regardless of barrel length

Seriously? I wish I was so lucky. I have to work hard to shoot under 2” groups at 600.

 

[Mike Hightower]

For 600 yards and in I like my barrels 23-24" Just MY experience I've got smaller groups with these lengths Possibly easier to tune? I've had barrels from 30" down and settled on these. Now if you will be using the gun out to 1k I would opt for something in the 28" length to give me more speed.

 

[kochie]

All those 6 BRA barrels on the wall are 28” for a reason.

View attachment 1568189

Dave.

ok thanks

 

[swd]

If you do a search of the daily bulletin’s there was an article probably 5+ years ago where a guy cut a 6BR barrel off one inch at a time and recorded the velocity’s. Great article, shouldn’t be hard to find. The jest of it was the straight BR doesn’t loose or gain a ton of speed with barrel length.. But find the article, it was very interesting!

 

[BRGUY]

Seriously? I wish I was so lucky. I have to work hard to shoot under 2” groups at 600.

Yes, dead serious!

I have to work hard at it too. Outside conditions, at least for me, are one of the hardest things to contend with when shooting groups at long range, with "mirage" being the toughest of all!

On a PERFECT day, I have shot many 1" or less groups @ 600 yards with various rifles that I own. 6mm-284, 244 H&H, 7mm STW, and 300 Weatherby Magnum are just a few of the rifles that have proven capable of this type of accuracy on more than a few occasions. I am also talking about 3-shot groups under an inch at 600 yards, since these are hunting rifles, but I have to admit that these rifles also wear long/heavy bull barrels with big scopes too.

Load development is the easy part.

 

[Kracken McGraw]

What’s the thinking between double based powders and single based on the barrel length?

 

[6BRA]

What’s the thinking between double based powders and single based on the barrel length?

Nothing really its your choice. Bbl life possibly. Double base will burn 95 percent in 7 to 9 inches. 100 percent in shorter bbls. My thinking is heat and throats. Everyone has an opinion...lol.

 

[kris bassett]

Reloading Powders | Gun Powders for rifle, handgun and shotgun | Handloading - Vihtavuori

Vihtavuori premium smokeless powders come in three different series: the N100 single base series and N500 high energy series for rifle and N300 for pistol.

www.vihtavuori.com

5 series VV powder
Pretty sure H322 is Double Base as well.

18" barrel, 87gr v-max, 28.7gr viht N133, 2793fps, 100% burn

 

[fatelvis]

In 6mm B-R I have the following barrel lengths -

16" XP-100

23" Remington 700

25" Remington 700

27" Remington 700

29" Remington 700

Optimal length - 27" but that depends on it's particular use.

What makes you like 27" the most out of your herd of 6BRs?

 

[BRGUY]

What makes you like 27" the most out of your herd of 6BRs?

Accuracy...

Velocity...

Trajectory...

I use this one for deer, coyotes, prairie dogs, etc...

It consistently shoots under 1/2" at 200 yards, even on a bad day!