Best twist rate for 7mm 180gr Berger Hybrids / VLDs and Sierra MatchKings?

[steve4661]

I'm about to get a .284 shehane built and I'm thinking of feeding it both 180gr Berger Hybrids and 180gr Sierra MatchKing's.

The Berger website recommends a 9 twist, but the Sierra website recommends an 8.
Should I go for an 9, 8 or 8.5 twist to handle both bullets?
Or do I really need to decide on just one bullet and go for a twist rate accordingly??

I'm not sure if the websites are referring to a minimum twist to stabilize the bullet, or an optimum twist for best performance of each respective bullet? If its simply the minimum twist then an 8 twist would probably be the best option to handle both bullets?

Looking at a stability calculator it looks like a 8 twist would be best for both. Just want to be sure I get the right twist before I blow my hard earned cash...

 

[mgdietrich]

I shot 500+ 180 SMK from a straight 284 with 9 twist. It shot very well. If you want an 8.5, that would be fine too but I wuld not go all the way to 8.

 

[Heman]

The reason Sierra recommends an 8 twist is because of people launching big bullets out of 7mm-08's as Paul Box told me. I have a 1:9 on the 280 Rem and it shoots 175gr SMKs, 180gr Hybrids, even the 189gr Cauterucio's just fine.

 

[Dgd6mm]

I have a .284 Shehane I bought off this site from a Gunsmith that built it and shoots. It is a 1-9, he placed well with it shooting the 180 Berger Hybrid at 1000 yards. I have a 7rsaum with a 1-9 that I've shoot 180 JLK's in that have let me place in the top 3 at 1000 yards. A 1-8.5 is about the fastest I would go.

 

[steve4661]

Thank you gentlemen, its sounding like my best option is to go with the 9 twist.

 

[barefooter56]

steve4661,
You may want to go with the 8 twist barrel instead. It will keep the VLD more stable as it passes through the trans and subsonic end stages of its flight , work for both bullets and take the worry out of bring close. Rule of thumb is "err to the faster twist rate". If you have any more questions please feel free to contact us here or at techsupport@bergerbullets.com.

 

[LKEYES]

I went with an 8 twist in a 7 mag I built a couple years back and it shoots very well.
Surprising though it over stabilized the 168's and they wouldn't group for anything.
I am running the 180 hunting VLD though and I haven't played with the Sierra MK at all.

 

[barefooter56]

LKEYES,
At what range were you shooing your groups at with the 168 grain bullets? 100, 200 yards? And was it the VLD HUNTING or CLASSIC HUNTER bullet or both?

 

[whatwind?]

8.7 for the 180's

 

[s100whunter]

8.75

 

[dragman]

9 is fine for most stuff, but if you want the stability out real long go with the 8.5 twist

 

[jvw2008]

Bartlein will make you a progressive twist that starts at 1:9 and finishes at 1:8.5.

 

[bsumoba]

Bartlein will make you a progressive twist that starts at 1:9 and finishes at 1:8.5.

Bartlien made me a couple 1:9 twist gain to 1:8.25, which is what they recommended to me. Should have no problems handling the 180gr hybrids as well as the potential 190+ gr hybrids if berger comes out with them

 

[LKEYES]

LKEYES,
At what range were you shooing your groups at with the 168 grain bullets? 100, 200 yards? And was it the VLD HUNTING or CLASSIC HUNTER bullet or both?

I was using the VLD Hunter and was shooting at a 200 yard target.

 

[barefooter56]

LKEYES,
200 is good. What kind of groups were you getting. And do you have any pictures of the target?

 

[yukonal]

I shoot 180 and 168 Hunting VLD's out of 2 different .284's, and they both hammer with 9 twists.

 

[DennisPA]

Ok dragman your scaring me!! I just got done putting a new 9 twist barrel in 7WSM for 1k at Ridgway. Are you saying I don't have enough twist to shoot the 180g hybrids??

 

[dragman]

Ok dragman your scaring me!! I just got done putting a new 9 twist barrel in 7WSM for 1k at Ridgway. Are you saying I don't have enough twist to shoot the 180g hybrids??

No no it will be fine for ridgway. My best shooting .284 was an 8.5 twist and if you go over 1000 like 1250,1300 I think the 8.5 keeps them stable longer.
My last 7SAUM was a 9 twist and it shot really well and I know lots of people that have shoot lots of great scores with 9 twists.

 

[Sniper338]

Id do a 8.5 personally.

 

[dalej]

I would go with a 1:8 barrel. Been experimenting with 200/210/215 gr bullets in 7mm. Think longer bullets will be available from the Bullet companies soon.