6mm br barrel twist

[mitchell]

hey fellas nices site you guys have here.

i'm about to build my first 6mmbr i'm wanting to shoot 65 &75 grain vmax's for paper and varmints out to about 500 yards with most shooting around 300 what twist is recomended for 65-75 grain bullets??

 

[Posit]

1-12". Just a thought, however: Most of the best 6mm BR results seem to be obtained with heavier ball and faster twist,1-8"). I know this because I have an excellent 300 yard 1-14" twist, but wish it was 1-8" to accomodate greater distance.

 

[mitchell]

well tell me your thoughts???

i have a 300 win mag shooting 185gr berger's, a 308 shooting 175 SMK, a 243 shooting 105's, so i realy got the 500-1000 covered i just want that 500 and in . i got a factory 223 but out past 300 it get kinda shabby.

so what do you think should i go with something bigger?? 87gr V max??

 

[Posit]

That was my thought - disjointed though it may have been.

Have you looked at 6mmbr.com,lots of good info there), and the 6mm threads on this site? A 1-8" twist is much more versatile, so if you're going to build something, why build in limitations? A 1-8" will shoot 75g Vmax,plus), and if you have overlap with other rifles, so what, as long as you can cover the zone you're missing?

My 1-14", shooting a 70g Sierra at 3240 fps, really starts to wander around 350,especially in a slight breeze); don't think a 1:12" will be much better. ,I have a 220 Swift, 50g ball at 3900 fps, which holds as good or even a tighter group at 350+ than the 6mm.)

Like you, I want something accurate to about 500 yards. I have it covered with a 25-06, but... gonna have my 6mm rebarreled.

Just my thoughts--

 

[rstreich]

mitchell, I set up my 6BR for exactly what you're describing. I decided to go with a 10-twist.

I've been out with several .243s shooting 58, 65, 75, and 87 V-Maxes. For me, the 65s do everything the 58s will do,in terms of terminal performance) and you get a little better wind resistance. The 75s will do almost as well as the 65s with even better wind resistance. The downside is that the recoil is starting to go up, and although they're almost as good, they just don't have quite as much destructive force as the 65s at the ranges you're talking about. The 87s are far superior in wind resistance, but there's a significant drop in terminal performance and a big jump in recoil.

So, the load I just worked up for mine uses 65 V-Max at about 3540 with H4895. I might get faster with a slower twist barrel, but I want the extra RPMs as that helps keep the destructive force high. I also wanted to shoot the 95 BIBs just for fun--man, do they shoot!

robert

 

[Clark]

75 gr Vax 3100 fps will go stable out to 50y, but not to 100y from my 1 in 14" twist 6mmBR.

That is right on the edge.

The 65 gr Vmax 3150 fps 1 in 14" twist have no trouble at 100y.

 

[gunsmithatwork]

My advice is to go with the faster twist brl's. With slow twist brl's you'll be stuck to the lightest bullets for your cal.; so Varmints are your only game! Any fast-twist 6mm brl in 8 or 9 twist,a 10 twist is not considered a fast-twist but a 'standard' twist) will shoot the lightest bullets just as accurate and can easily handle the heavyweight bullets, just in case you decide to built a ' true'multi-purpose 6mm rifle,as I have build dozens) and planning to shoot it at medium to long shooting ranges for both target-, & varmint-shooting aswell as hunting medium-sized game? Also: the heavier bullets are the only true 'winners' if shooting under less then ideal weather-conditions; such as wind! A fast twist brl; say in 6mmBR. will still get you plenty velocity & accuracy in the shorter brl-lengths between 18-21"; wich lengths, from experience, make very handy hunting & varmint rifles. Go for a fluted #4 or #5 contour fast-twist brl at 21" length and you'll be surprised what it is capable of! Hope this helps?
Jan

 

[NateHaler]

That was my thought - disjointed though it may have been.

Have you looked at 6mmbr.com,lots of good info there), and the 6mm threads on this site?

This IS 6mmbr.com.