6mm BR Issue

[SST2500]

Guys. I have a 6mm BR that currently has 220 rounds thru it. I have worked up loads with both the 110gr. Hornady A-Tip and the Berger 109 gr. Hybrid Target. I’m using Lapua brass with the necks turned to 0.125 which cleaned up about 85% of the necks. I have loads worked up with Varget and H4895 which will both shoot groups in the 2’s. My problem is that every load that will shoot this well will put 4 rounds into a 0.2” or 0.25” group and then throw one round out that increases the group to 0.40 or 0.50. It’s never the same shot but it seems to be consistent at throwing one round out of the group. It could just be my shooting, lol, but even a blind hog finds an acorn on occasion so I believe its an ammo or rifle issue. The rifle is a Rem 700 action with a Preferred Remage barrel in a laminated stock that has been pillar bedded. I haven’t bedded the recoil lug yet but I just don’t think that’s going to cure these flyers. I checked the Varget load and it was running an SD of 6 so I don’t think it‘s a powder problem. Any suggestions on what to try next to remove these flyers would be appreciated.

 

[Forum Boss]

1. Have someone else shoot the gun. Very possible error is shooter.
2. Check stock for fore-arm flex. We had one gun that would do this (Kick flyers because of stock flex). You might test by pulling front rest back.
3. I have seen this phenomenon many times. Sometimes cured with a better barrel.
4. SD of 6 ain’t so great. Look at your ES. Under 15 ES is what you want. That said, ES is not critical at 100, but it is an indicator of good reloading methods.
5. Try marking “flyer” brass and using that for sighters. I did this and it resulted in better Match results. I could never find anything objectively wrong with the brass but my scores improved when I segregated the flyer brass.

 

[SST2500]

Thanks for the info. Marking the flyer brass sounds like a handy trick. I’ll start doing that at the next range session. My next fix is to bed the recoil lug and see if that helps.

 

[Henryrifle]

@SST2500: I'd definitely bed the recoil lug and rear tang too. What you're experiencing sounds just like the kind of thing bedding can fix. Not guaranteed to work but figuring out a problem often involves eliminating variables.

Thank's, Forum Boss, for a master lesson in this kind of thing!

Henryrifle

 

[Texas10]

Until recently, I too was chasing that rabbit while shooting 6mmBR in for score matches. I don't neck turn, as my barrel is not reamed for tight necks, and I'm shooting 107 SMK's over Varget. The rifle is a Savage Target action built by SSS with a Brux 4 groove, 8 twist.

I was consistently shooting in the high 240's but never cleaning all the targets until I took a close look at my powder scale. It's an RCBS 10-10 built by Ohaus, and apparently it was not consistent.

After some careful cleaning and tuning, it is now sensitive enough that I can detect two kernels of powder. The fliers have vanished. Last match I scored a 250-13X, a big improvement for me.

You might start by charging 10 cartridges and then pour each charge back onto the scale and see if there is any differences. If you're using an electronic scale, wait a day or two to recheck the charge weight. There could be a variety of environmental issues affecting an electronic scale.

 

[RichMoAK]

Is the flyer consistently horizontal or consistently vertical OR not consistent at all, random POI? If you could find some pattern in the flyers, you might be able to narrow down your search for the culprit(s).

 

[JFrank]

Posting a target will help out, I'm always interested in load data too

 

[JEFFPPC]

Flags?

 

[Idaho-Lefty]

Bed, IT,.. now, to stop, Recoil "movement" ( could be "Binding" if not, "leveled" on, Pillars / bottom of Lug area ! ) Be sure to SUPPORT, the Barrels "Shank" portion, too ! ( I like about, 1.5" of, bedding compound, "support" under shank ). And, carefully check, Screw "tightness" !
Might try, a slightly SLOWER, "burn rate" of, a VhitaVouri, Powder with, those, Heavy Bullets.
All,.. JMHO

 

[Forum Boss]

I will add that we had one notable 6mmBR rifle originally chambered as .260 Rem. It always gave fliers with the factory .260 barrel. Switched to custom barrel. No more flyers. Stock, bedding, action, trigger, scope, rests, shooter, all unchanged. Lapua Brass and Scenar bullets for both. So part of it was new chambering but I give most credit to new barrel. Here are NINE 3-shot groups. Notice something? That's right -- ZERO fliers.

 

[SST2500]

This a recent pic of a Ladder test with H4895 and Berger 109 gr. Hybrid Target bullets. These were seated 0.012 into the lands. Both are 5 shot groups (I like to shoot 5 shots of the same load when ladder testing). As you can see, there’s always a flyer when I hit a good node.

 

[LHSmith]

I’m using Lapua brass with the necks turned to 0.125 which cleaned up about 85% of the necks. I haven’t bedded the recoil lug yet but I just don’t think that’s going to cure these flyers.

1/8" is way too thick for necks- LOL. I suggest to bed the lug. Are you certain you have all parallax adjusted out? Also bag set-up. Make sure everything is the same and be mindful that your fore-end is contacting the rest stop each time. Flags and watch for mirage.

 

[expiper]

This a recent pic of a Ladder test with H4895 and Berger 109 gr. Hybrid Target bullets. These were seated 0.012 into the lands. Both are 5 shot groups (I like to shoot 5 shots of the same load when ladder testing). As you can see, there’s always a flyer when I hit a good node.

three shot groups tell how the gun is doing,,,five shot groups tell how the shooter is doing,,,,Roger

 

[CNC-Dude]

1/8" is way too thick for necks- LOL. I suggest to bed the lug. Are you certain you have all parallax adjusted out? Also bag set-up. Make sure everything is the same and be mindful that your fore-end is contacting the rest stop each time. Flags and watch for mirage.

I had that exact same issue on my RPR and it was the parallax needing to be fine tuned. That fixed it!

 

[boltfluter]

Bedding is first on my list for accurizing a rifle. Your groups are classic for a bedding problem. The old saying of " bedding, barrel, and bullets, or the 3b's is very true. Good luck.

Paul

 

[INTJ]

This a recent pic of a Ladder test with H4895 and Berger 109 gr. Hybrid Target bullets. These were seated 0.012 into the lands. Both are 5 shot groups (I like to shoot 5 shots of the same load when ladder testing). As you can see, there’s always a flyer when I hit a good node.

I agree, 5-shot groups are correct if we really want to evaluate a load. That said, many have had less than stellar groups with the Berger 109s. If you really want to eliminate the bullet as a variable, use the Berger 108 BT Target. Make sure you sort them BTO, and they will most likely be happy to jump. That bullet is usually easy to tune in the 6 BR variants.

 

[jackieschmidt]

Bullets?
You are attempting Benchrest consistency with semi custom bullets.

 

[SST2500]

Thanks guys. Yes 1/8” is way to thick for necks, lol. Maybe 0.0125 would help. I guess bedding the recoil lug is next. Since this is a Remage setup it would be difficult to bed the first 1.5” of barrel due to the barrel nut.

 

[SST2500]

I’ve shot the Berger 108’s and they didn’t shoot as well as the 109’s. Actually, the new Hornady 110 gr. A-tip bullet has been the most consistent bullet for accuracy. I tried the 115gr. DTAC and at 100 yds the verticals were no good. I’m not sure what bullets one would consider to be “benchrest” bullets as I know a number of benchrest shooters that use Berger bullets.

 

[Bill Norris]

three shot groups tell how the gun is doing,,,five shot groups tell how the shooter is doing,,,,Roger

I have found this to be true from years way back in the mid-90's to date it seems to be the case for me as well.