ideas for the optimum twist rate for using 117s in a 6XC

[ratgun6]

A friend called and asked if I could reccommend a twist rate for a 6XC he was having built. He mentioned that he was interested in shooting HP "across the course" matches but also wanted to use it at 1000yds and would be using the Tubb 117. I suggested a 30" SS Bartlein 5R 1:8 as it would work well with 105-108 gr bullets. I'm not sure how it will work with 117s. Does anyone have experience with this.
thanks
don

 

[abishai]

As far as I know the 117s are unavailable / discontinued because of poor performance. A 1-8 will do just fine for the 115 dtacs, or at least it does on my xc, 243, and brx. IMHO a 1 - 7.8 would be better.

 

[Dgd6mm]

A 1-8 for the 115 DTAC may work for some, but not all, if it's a button rifled barrel. A 1-7.5 will work. 7.8 is supposed to be minimum twist. I know someone else will let you know what barrel in a 1-8 works for them.
If I was going to shoot out to 1000 I'd go 7.5, but thats just me.

 

[ratgun6]

I appreciate the info and I'll pass it along.

Thanks
don

 

[spclark]

1:7.5 to be safe with the DTAC 115. I have a 30" Bartlein 1:7.8 in 6XC that I bought thinking I could shoot 'em... much prefer the Berger 105VLD (or their new 105 Hybrid) after initial break-in & testing... out to 1,200 yards.

117's were never generally available & that was several years back. As was posted previously, they don't exist.

 

[DukeDuke]

I shoot 117s and the 1-7.8" Broughton loves them. I bought some, back in the day. Very sad they were discontinued.

 

[ratgun6]

Thanks - sounds like something faster than 1:8 for the 115s + heavier will do the trick. I've passed the info along - we'll see what he does with it. For my sake I hope he tries a 1:10 maybe that way i can keep ahead of him with my little 6BR at 1k.

 

[attherange]

1-7 to 1-8 seems to be the norm with the long heavies 115.

 

[Ironworker]

I have a 1-8" Twist Brux 6x284 will it stabilize 115gr missiles ?

 

[spclark]

I have a 1-8" Twist Brux 6x284 will it stabilize 115gr missiles ?

DTAC's maybe. Berger's? Not too likely.

With that cartridge you have a distinct advantage in powder volume that ought to make lighter, 105 - 108 grain bullets really shine. The DTAC 115 doesn't have a significant ballistic advantage over the Berger 105VLD anyway & the latter is more reliably available.

 

[wboggs]

The Berger 105 Hybrid is now my preferred bullet in 6xc. Stabilizes fine out to 1000, very accurate at around 3000fps.

 

[wboggs]

Forgot to mention that I use a Krieger 1-8.

 

[flatlander]

I've got 6x47 bbls. in .236" & .237" bores, twists from 7.5 to 8. Comparing data between them, my feeling that a .236"/1:7.5 is overkill when it comes to shooting 115s, whether they're Bergers or DTACs. If I were to try another 7.5tw, it'd have a .237" bore. I've got two of the .236/7.5s, and one .237/8, and have found that the .237/8 will shoot either of the 115s just as well - if not better than - either of the .236/7.5s, and that's out to 1000yds.
I do have a Bartlein 5R .237'/1:7.8 med Palma bbl. sitting out in the shop, and will eventually get around to replacing a .236"/1:7.5 med Palma with it on my BAT 3-lug prone rifle - if I decide to stick with 115s at 1000. If I instead go with the new Hybrids, I'll go with a 1:8.

 

[1shot]

+1 to what Dennis says. I'm shooting a 6mm SLR, I got it chambered when Robert W. was still calling it the 6mmSX. The bbl. is a 1-7.75" Krieger and it will drive 105 or 115 pills flawlessly. Personally, I get a distinct advantage with the 115 JLK bullets at 1K, but shoot the 105's at 600 like you won’t believe. At one match my shooting partner said that he could tell every time I fired because the BOOM and the impact we nearly at the same time at 600. In short, in 6mm, give me a .237 bore with the above rate of twist and everything else is up to the nut behind the trigger.
I hope this helps,
Lloyd