6mmBR for 600Yds

[ArtinNC]

I have a 6mmBr with a L&W barrel 29"long 1:8 twist and a .080 lead for shooting 105 Berger and JLK bullets for a 600yd gun. I can get the gun to group with 80gr Bergers under .200, and some under .100 ) but with the 105gr bullets it groups around 1 inch. Need some HELP.
Thanks,Art

 

[Preacher]

If your using the new JLK's 105's they really need to be checked over for bearing lengths before shooting them.
Someone with more knowledge than I have might disagree, but I think that a .080 lead is kinda short for the longer bullets, and that a .110 or more is ideal......

 

[Cheechako]

Hey Art, if you have a combination that groups in the ones, with an occasional zero, why are you looking further??? That is your "good condition" bullet and load. For the snotty conditions it will definitely pay to have a higher BC bullet but don't expect it to group as well as that 80 grain load. I look at it this way - if conditions are bad, I am not going to be shooting 1 inch groups at 600 yards no matter what bullet I am using. I am struggling to keep from shooting any BIG ones.

Try some different bullets. The 107 Sierra, the 95 Berger, the 95 BIB for example. One of them will probably shoot. Maybe your barrel simply doesn't like the 105 Berger and JLK. No sense in wearing your barrel out beating a dead horse.

I wouldn't shoot 600 yards with just one gun/bullet/load. Competition is getting fierce and it's to the point where you have to be ready to jump on the good conditions with a super accurate load that will shoot 1-inch groups, but be ready to switch to something with a higher BC,but less accurate) when the zephyers blow. Having but one load that shoots OK in all conditions will get you some respectable groups and scores but not much fake wood at the A Wards ceremony. JMHO

Ray

 

[ArtinNC]

Cheechako,
I have never shot this gun past 100yds and that has been in a barn so no wind. I'm not the best shooter but I have another gun that I can shoot in the high 2" and low 3" inches at 600yds and in the .200 or less at 100yds in the Barn, it has a 1:9 twist and shoots 95gr Bergers. I built this gun to shoot heaver bullets, 105gr )and has 1:8 twist but it likes 80gr best. WHY? I can't shoot good enough to win a match but would like to shoot some respertable groups. Art
PS: Maybe I'll try 80grs bullets at 600yds.

 

[Cheechako]

Art

Try the 80s at 600. If they shoot little dots at 100 they will probably shoot at 600 also. My "good condition" gun for 600 yard NBRSA is a 6PPC shooting 70 grain bullets at 3385 fps in a 12 twist. Don't let anyone tell you that you need a heavy bullet, except in windy conditions, where I'll agree that you do but only to a certain point. Next year I am trying 95 grain BIBs. 600 yards is getting to be a lot like point-blank Benchrest. You need accuracy, and lots of it, to win.

Ray

 

[ArtinNC]

Guess I could just shot my old gun and saved a lot of MONEY ?
I'll try the 80's at 600yds this next week and see how i do . Thanks,Art

 

[Forum Boss]

Art,

First, measure your actual twist. If your barrel is really a 1 in 8.5" or so, there may lie your problem,with the 105s).

Second, play with seating depth. You can push the Berger 105s well into the rifling. I'd start about .015" or so.

As others have suggested, try other bullets. I'd try some Sierra 107s and Scenar 105s. But this assumes you've confirmed your twist rate. If you really have something closer to a 1:9, try the Berger 95s or BIB 95s.

A barrel that can toss Berger 80s into .20" or less is not a bad barrel. There's something going on that a little more research might reveal.

 

[jb1000br]

Would not be surprised to find out you don't actually HAVE an 8-twist...

 

[ArtinNC]

Just checked the twist it's not 8 and it's not a 9, butI showed it at more than 8 1/2 checked it 4 times . So I guess I'll have to stay with 95 gr bullets . Art

 

[Forum Boss]

Just checked the twist it's not 8 and it's not a 9, butI showed it at more than 8 1/2 checked it 4 times . So I guess I'll have to stay with 95 gr bullets . Art

Art,

With an 8 1/2 twist you might try the Berger standard match 105s,formerly LTB length tolerant bullet), and the Lapua Scenar 105s, in that order. I have a friend with a BRX that is stabilizing the Scenar 105s in an 8.5. But he's pushing them over 3000 fps.

 

[Rustystud]

Art:

Check out John708s project gun,6mmBRX). He just shot the 4 F-Class 600 yard matches clean with 89 Xs. He is going to shoot it at 1000 next month. He has it figured out with 105s and 107s. 32.5 grains of Varget with a 32 inch Broughton 6mm 1:8 5C barrel. He is averaging .38 ten shot groups at 100 yards.
It is just a little hotter,3 grains of powder) than a stock 6BR. He is getting approx. 3,070 fps with the best load
Rustystud

 

[ArtinNC]

Rustystud,
I'v been following it . I haven't had a chance to use my new toys yet. Probley will be a couple of weeks.
Art

 

[Rustystud]

Art:

When you get to chambering with that new toy you will say how did I live without it all these years. If you need any help don't hesitate to call.
Rustystud a/k/a Nathaniel G. Lambeth, Sr.