Most Accurate 6mmBR Bullet Weight/Twist - Short Range

[Phil3]

After reading about the 6mmBR on this site and others, I understand what bullets work best with what twists, and that heavier bullets are needed for longer distances. But what I don't know is what bullets (and resulting twist) are best from 100 - 300 yards. I could use light bullets in a 1:12 twist or heavy bullets in a 1:8 twist, but don't know if one of those choices offer an accuracy advantage over the other at 100 - 300 yards. I know the lighter bullets are more affected by any wind.

Thank you.

Phil

 

[Toby Bradshaw]

Since virtually all of the short-range (100-300yd) BR group shooting crowd are using 62-68gr bullets in 13.5-14 twist barrels, you'd be safe going that route with a 6BR.

 

[Tim Singleton]

I had a hard time finding a prefIt supplier that offered a 14 twist. So I built a 12 twist it is in a tracker stock. It likes 80 gr Bergers.

I would recommend a12 twist then you can shoot 55gr up to 80gr bullets awesome out to 300 yards

Like I said if you going prefIt 12 is probably as slow as you will find

 

[mikecr]

The answer depends on the bullet chosen.
Most accurate would likely be light flat base bench rest bullets, With these way lower twists can be used(causing less torque).

 

[clatarar]

The 88 grain berger would be my bullet of choice for 100-300 yard shots.

 

[waterfwlr]

12 twist and 80gr Bergers. Outstanding.

 

[NorCalMikie]

Go 1-8 twist with a short throat (so you can jam them into the lands) for starting out with 45 and 50 grain bullets and as the throat gets longer (and it will, sooner than you might expect) you can go to heavier bullets. Nothing worse than getting a chamber with the throat too long and the bullets of your choice won't reach the lands. Get your chamber cut to your dummy round loaded with the bullet of YOUR choice. A five shot group that measures .110 from 100 yards will put a smile on anybodys face. ;D

 

[littlebuddybr]

Since virtually all of the short-range (100-300yd) BR group shooting crowd are using 62-68gr bullets in 13.5-14 twist barrels, you'd be safe going that route with a 6BR.

+1

 

[Terry]

The answer depends on the bullet chosen.
Most accurate would likely be light flat base bench rest bullets, With these way lower twists can be used(causing less torque).

Pac-Nor made a 1:14 for me.

Savage prefit.

 

[MarkS]

Phil,

I have had them aii. 14 thru 8 tw. The most accurate one I had was a Lilja 12 tw shooting Fowler 80gr bullets, made be Jeff Fowler himself, Jeff has past now but I not tried the new Fowler's http://www.fowlerbullets.com/. I shoot the 80gr Berger's now. I built this gun for egg shoots. see http://www.6mmbr.com/Schronce600.html. I now shoot 8tw with 105gr, 108gr,and 80gr. The 8tw will shoot the 80gr the same as the 12 tw. The 68gr work great at 100 and 200, but the 80gr will do very well out to 600 yds.

Mark Schronce

 

[wapiti25]

A 12 twist likes 65-80gr bullets. The Berger 88gr requires a faster twist. 80gr Bergers work real good at 300yds, 70's not as good for me in a 12 twist at 300yds. I hear a lot of guys are shooting the 13.5 twist with the 65gr bullets in competition. It really depends on how you are going to use the rifle, for short range competion the 6PPC is hard to beat with the 6BR.

 

[Phil3]

Go 1-8 twist with a short throat (so you can jam them into the lands) for starting out with 45 and 50 grain bullets and as the throat gets longer (and it will, sooner than you might expect) you can go to heavier bullets. Nothing worse than getting a chamber with the throat too long and the bullets of your choice won't reach the lands. Get your chamber cut to your dummy round loaded with the bullet of YOUR choice. A five shot group that measures .110 from 100 yards will put a smile on anybodys face. ;D

An interesting approach, to use a faster twist barrel, because the throat will wear, forcing use of longer bullets (which require faster twist) to reach lands.

With regards to 45 to 50 grain bullets, I can't find any Sierra or Berger bullets that light. 62 grain is the lightest target bullet I see on MidwayUSA. Your message makes it clear that the bullets are expected to reach the lands. Is it accepted practice that in the 6mmBR, superior accuracy is always realized with the bullet touching or jammed into the lands?

The recommendation to choose my bullet and cut the chamber to match is a Catch-22 situation. I have no preferred bullet, only the one that gives me best accuracy, but how can one know that without experimenting, which requires a chambered barrel in the first place.

Phil

 

[boltman223]

Go 1-8 twist with a short throat (so you can jam them into the lands) for starting out with 45 and 50 grain bullets and as the throat gets longer (and it will, sooner than you might expect) you can go to heavier bullets.

But everyone says that fast twist aren't accurate with light bullets.?

 

[NorCalMikie]

Phil:
The only problem with ordering a "Pre Fit" off the shelf barrel is you're stuck with what they sell and have in stock.
Every barrel I have is chambered so I can jam the bullets into the lands. That's my starting point.
In the last few years, the barrel makers have gone to a better chamber selection so your chances of getting one that you prefer is much better. Maybe not exactly what you want but I'am thinking pretty close. Better yet, get your own reamer cut to your specs and buy blanks barrels. But that's further down the road.

When I ordered my second 6 BR barrel (from Shilen), I built a dummy round with the lightest bullet I could find seated to the shoulder neck junction and had it cut so the bullets (of MY choice) were jammed into the lands. And like I said, as the throat wears, I can go to a longer OAL, jam into the lands and still have a bunch of bullet in the case neck. I think I'am up to 60s now and still have a lot of bullet/neck contact. Maybe 500+ rounds fired?
My first barrel had the throat too long (off the shelf chamber) and I was stuck with heavier bullets than I wanted to shoot. That's where the short throat chamber works best. You order it the way "YOU" want it. The longer throated barrel went down the road to someone that wanted to shoot heavier bullets than I did.
All my loads are built and tuned with the bullets jammed .010 "into" the lands. If I started out with a jump to the lands, with a higher powder charge I would start running into pressure signs. Stiff bolt lift and shorter case life.
With that same "higher powder charge" and the bullets jammed into the lands, no pressure signs I could go further up in powder charge with no more pressure problems.

You're not buying "factory ammo", you're rolling your own so you're experimenting from the start. You end tweaking your loads to get the best accuracy you can. That the fun part.

The first rounds I ever shot out of my 6BR gave me a 5 shot group that I could cover with a dime @ 100 yards. I was hooked!!
What it boils down to is you have to choose the freebore for the bullet you plan to shoot.
Short throat for lighter bullets and longer for heavier bullets. Nothing wrong with having two different throated barrels. 8)
As far as lighter bullets for the 6BR, Berger and Sierra arn't the only bullet makers.
You can go with a Berger VLD, stuffed "into the lands" and still have a bunch of bullet/neck contact. I've got 60 grain Noslers that work like a champ and are deadly accurate.
The Berger VLDs take a shorter throat (to reach the lands) because of their design.
Even picked up some Remington bullets that were butt ugly and still produced bugholes.
Reloading is a guessing game and there's not a thing wrong with "trigger time". That's where you find the best load for YOUR rifle.

 

[GSPV]

You might change some specifics, but I posted this long ago. Posting it once again.

----

Phil needs to quit yammering and start building.

1. Call Jim Briggs at Northland Shooters Supply (763) 682-4296
2. Tell him that you want a starter rifle in no turn 6 BR for the 104-107 bullets.
3. Do what he tells you to do without oscillating all over the scope.
4. Put a Sightron 10-50 on it in Burris Signature Z rings.
5. Get a cheapie press, Redding Type S FL bushing die, a 266 bushing, Imperial sizing die wax, a Forster Micrometer seater die, K&M Expandiron with 6mm mandrel, Lee length trimmer with 6BR holder, a rocket-style chamfer tool, Ohaus 505-type balance, a cheap trickler, K&M priming tool and #2 Lee AutoPrime shell holder and a 6 BR shell holder for the press.
6. Buy Lapua brass, CCI 450 primers, Varget and 107 SMKs.
7. Buy electronic digital calipers. Mitutoyo is good but expensive.
8. Run the brass over the 6mm mandrel and FL size them before you load them the first time.
9. Buy a bipod or front rest and a rear bag that matches up.
10. Prime, flat side out, drop 30 grains of Varget and seat that SMK 12 thou into the lands.
11. Go shoot. Evaluate. Post specific, questions and incrementally apply fixes.
12. Measure your brass and trim to ~1.550. Chamfer inside and out. Go back to 10 and repeat.

Now, Phil, that leaves a bit out, but it does cover 90%. So, it's poop or get off the pot, dude. Seek to simplify, not complicate.

 

[Phil3]

NorCalMikie,

Thank you for thorough reply.

First, I rather doubt I will be using an off the shelf prefit barrel. I would like to buy a blank and have it chambered. For the most part, off the shelf barrels (Savage) have little to no info on the reamer used. I though about contacting Dave Kiff at PTG and asking him what reamer to use for my purposes.

Curious to me pressure signs would materialize with a jump to the lands. I would think the converse is true.

Any suggestions for choosing a best bullet that will see most use at 100 yards, some at 200, and rarely at 300 yards?

Phil

 

[NorCalMikie]

Greg:
Well said.
On my first long throated 6 BR barrel, I stuffed the bullets in a powered case and went shooting,
seated way off the lands but still deadly accurate and it MADE MY DAY!! 8) I went from there.

Phil:
I shoot Nosler seconds 55 grain spitzers with deadly accuracy. Sierra makes the 55s also.
The accuracy will be real hard to believe.
As far as seating depth, you need to see what works best for YOU. Not all rigs shoot the same.
I started with the jam and it has worked VERY WELL for me. Try it for yourself and work from there. You need to start somewhere. Dave Kiff at PT&G can give you the straight skinny. He knows his stuff!

 

[waterfwlr]

With prefits, you are not stuck with what is in stock. You can order anything you want with different chambers to choose from with reamer prints.

 

[Phil3]

With prefits, you are not stuck with what is in stock. You can order anything you want with different chambers to choose from with reamer prints.

Thank you. Looks like I will be delving into the world of reamers. I intend to call Dave Kiff at PTG. Just to be clear, I may be using a prefit and/or a standard shoulder type barrel. I have a Savage (prefit) and Howa (shouldered barrel) action coming in of which one or both will be shooting 6mmBR. Depends on the outcome of a Howa 6mmBR project I am working on.

Phil

 

[Medic505]

LMAO..... sounds like GSPV lives at a Holiday Inn Express.