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Old April 6, 2019, 08:02 PM   #1
the blur
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BAR won't group

7mm-08 BAR. I had a well known gun smith work on it. Redid the crown, bedded it, cleaned it professionally.

Still doesn't group.
I tried light & heavy loads.
All different ammo.

I'm ready to move on.

Any ideas what to do with a rifle that wont group ?
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Old April 6, 2019, 08:41 PM   #2
big al hunter
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If nothing else it would make a lovely tomato stake.

On a more serious note, how do you support the gun. And what size groups are you getting?
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Old April 6, 2019, 08:54 PM   #3
the blur
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6" groups.
Sand bags.
rear bag as well.


My X-bolt shoots 1"groups at 200 yards.

It's really too bad, I love the BAR.
I love hunting with a semi.

I have a .243 BAR that groups sub 1 MOA
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Old April 6, 2019, 09:01 PM   #4
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If there's no obvious flaw in the rifling near the muzzle, then something is loose on that gun. I'd start with the scope and scope mount.
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Old April 6, 2019, 09:08 PM   #5
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I would agree with John. Check scope mount first. Try a different scope known to perform well. Does it start out shooting wildly large groups, or is it growing larger with each shot?
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Old April 6, 2019, 09:47 PM   #6
the blur
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The scope is indeed tight. Mounted, leveled, bore sighted, range sighted.
Its a high end ZEISS.

Maybe the cross hairs are jumping inside the scope. Doubtfully, but you never know...

9.5" twist. Which should work well with 140 ammo.
But 120gr ammo groups better than heavier ammo.


and I have cheap scopes on my other rifles, that group better.
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Old April 6, 2019, 10:04 PM   #7
big al hunter
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Even the best quality control and materials still have issues occasionally. Try a known good scope. Or put that scope on a known good rifle/load combo. Make sure the for stock is attached properly as well. Try to wiggle the fore stock and the barrel. I had an issue with my 22 many years ago. It kept getting worse accuracy as time went on. When I got to looking at it I discovered that the barrel nut had come loose. The muzzle would move nearly 1/2 inch back and forth. I tightened the nut and solved the problem. Sometimes a little wiggle shows where the problem lies.
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Old April 6, 2019, 10:46 PM   #8
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"Since 7mm08 is, from a case capacity perspective, best for 100gr-140gr projectiles, it makes sense to provide a twist rate that hits that sweet spot and doesn't try to overspin the bullets and lose some incremental velocity as a result". This was stated by another person which made sense to me when I was trying to figure out why my brother 7mm08 did not like the 140 grainers. Consider shooting the 100 grainers it will group better than the 120 but if you insist on the 140 grainers I recommend the Remington cor-lokt which shot surprising well. Must be in the bullet design, maybe the base is wider, don't know for sure.
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Old April 7, 2019, 07:31 AM   #9
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It's been ages since I had a BAR and mine was quite accurate as I remember. I'm just wondering if it I s possible to shoot that gun with the forend removed? Maybe something in that assembly is putting some sort of pressure on the barrel when it is attached. Is it one of those models that has the BOSS system?
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Old April 7, 2019, 05:59 PM   #10
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All the bedding, crown work etc is not gonna help if the barrel is bad... I’d replace the barrel before calling it quits.

If it was me, I’d only pay what it’s worht less the cost of barrel and gunsmith to install.
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Old April 7, 2019, 06:08 PM   #11
the blur
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It's a 9.5 twist.... which is supposed to like heavier ammo. If I can only shoot 120gr or less, I'd rather hunt with my .243 or 6.5

Maybe the barrel is toasted, but I figured the gun smith would have let me know...


I don't have a range gun. I have hunting rifles. So when I go to the range, I practice with my field rifle. They do heat up, then I let them cool down while I shoot another gun.

Maybe it's time for a new 7mm-08. I love the caliber. It kills Elk, no problem. Minimum recoil.
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Old April 7, 2019, 06:21 PM   #12
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1:9-1:10 is about standard for 150-180gr bullets.
What weight bullets have you been shooting?
Handload our factory ammo?
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Old April 7, 2019, 06:27 PM   #13
the blur
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I normally shoot 140. I tried 150, which is about max for 7mm-08.
It likes 120 better than anything, but still doesn't group well.

All factory loads. and I tried every which brand out there, including Nosler, Browning, and pricey stuff.
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Old April 7, 2019, 06:32 PM   #14
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I’d go to a different gunsmith to check the accuracy issues. Slug the barrel, chamber cast, etc. But, I suspect it just needs a new barrel regardless
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Old April 8, 2019, 10:22 AM   #15
Art Eatman
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My local gunsmith just wandered in and saw the thread title.

He's working on a similar BAR problem. His belief, based on prior experience, is that it's the gas system. If ejected cartridge cases do not "clump" close to one another upon ejection, that's a clue.

He's still working on a solution.

PM me in a week or so; I might have more info.
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Old April 8, 2019, 10:32 AM   #16
the blur
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So my ejected brass needs to group as well ??

You can believe me, it's not the scope mounting. It's nothing obvious, nothing is loose. I went over the gun. A well known smith did the crown, and bedding, and cleaned it.

Maybe it is the gas system... which I don't know anything about.
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Old April 8, 2019, 11:04 AM   #17
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Some semi's shoot well enough, some don't. I got better things to worry about than trying to get a rifle to shoot. If it doesn't shoot close to 1 MOA out of the box it gets a new home. If some minor tweaking gets it better than 1 MOA that is great.

If it were mine it would have been gone BEFORE I spent money on it. It sounds like this one was bad enough that it should have gone back to Browning. I don't know if they will work with you after being worked on by someone else or not.
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Old April 8, 2019, 04:09 PM   #18
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If the receiver & barrel heats-up too much, it's possible groups would tend to walk vertical strings. If so...shoot a 3 shot group in a fairly rapid pace (before the receiver heats-up) --- then let the big gun cool.
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Old June 5, 2019, 03:18 PM   #19
the blur
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Art Eatman, did your gun smith ever find a solution ?

My BAR still doesn't group. I tried 2 high end scopes. Gun won't even group at 50 yards.
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Old June 5, 2019, 05:04 PM   #20
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I've had some pretty terrible rifles I could make group at 50 yards even if using only Kentucky windage.
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Old June 5, 2019, 06:09 PM   #21
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I just bought a new BAR with the 10 shot DBM. It wont group either....
I think Im going to send it back to Browning...…….
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Old June 5, 2019, 09:33 PM   #22
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I won't say I have the answer,but I do have a theory. My older brother had one that quit grouping.After some frustration he sold it.
First,the OP says 6 MOA. A rough bore beat up battle rifle from WW1 with no bedding work will usually beat 6MOA. With all due respect,I think the twist is close enough for 120 to 140 gr bullets,and unless the OP can see a gross barrel problem,the rifle ought to shoot as well as nearly any lever deer rifle,at least better than 6 MOA


Long ago a buddy of mine cut a beautiful contoured tapered octagon barrel in 45-70 fot a Martini action. He cut a dovetail across the underside
of the barrel to hang the forend.

That dovetail ruined he harmonics of the barrel.t was a huge stress riser.

The rifle would shoot very mild loads quite well,but approach 1886 Win tier loads,and it scattered.

This post got my curiosity up,so I went to YouTube. This smith is just doing a teardown/clean job. I can see the disassembled rifle.

Browning cut a very large dovetail across the underside of the barrel to hang the gas cylinder.

I just won't cut a barrel that way. You will notice the bolt rifles with dovetail barrel sights have a ring of thicker steel profiled in the barrel for the dovetail.


I suppose in some cases the stress relief,barrel harmonics and dovetail fit work out,so some of these rifles shoot well.

IMO,its a poor design


Another little thing that might be important. What is the front sling swivel screw also holds the forend on. It threads into that gas cyl dovetailed into the barrel.

If you sling swivel rests on the bag,its a rigid post to the gas cyl,then to the dovetail,which is a barrel stress riser.That,IMO,is probably worse than resting a barrel without a dovetail on a hard surface. Its going to bounce.


Try being certain no contact with the swivel s made to the bag.


I know very mid loads are not a solution on an elk rifle,but you might try some to learn if harmonics are an issue. If it shoots better,thats a clue.Not real good news,but it ndicates the dovetail

https://youtu.be/MZD2RMCKAXw

Last edited by HiBC; June 5, 2019 at 09:49 PM.
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Old June 6, 2019, 11:33 AM   #23
Art Eatman
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Erratic groups resulted from problems in the gas system. Sticky piston. Made for variable harmonics, apparently. It was noticed from the variable distances of ejected cases.

Groups improved after cleaning the system. All other usual efforts had made no improvements.
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Old June 6, 2019, 11:49 AM   #24
Jim Watson
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Browning allegedly "discovered" the BOSS tuner by noticing that a slight shortening of the barrel would improve accuracy of problem rifles.

But I would scour out the gas system first.
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