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Posted: 8/22/2005 1:50:18 PM EDT
Can someone who has firsthand knowledge tell me what the difference is between 1x7 and 1x9 barrel twists?  Everywhere I look somebody says something different...

My main concern what bullet weights can be used and what bullet weights should be used with each barrel.
Link Posted: 8/22/2005 2:08:35 PM EDT
[#1]
+1

I have a chance at a good deal on a 16" Clot 1/7 barrel.

Well?

What say you?

Link Posted: 8/22/2005 2:17:50 PM EDT
[#2]

Quoted:
+1

I have a chance at a good deal on a 16" Clot 1/7 barrel.

Well?

What say you?




If you decide not to go for that 1/7 deal, pass it onto me
Link Posted: 8/22/2005 2:33:44 PM EDT
[#3]
1/9 is good for lower weights 45 gr 55 gr 62 gr .  1/7 is good for 62 gr 70 gr 72gr  .......IMO
Link Posted: 8/22/2005 2:35:35 PM EDT
[#4]
I own several rifles in both twists and like them both. Here are my observations, based on the rifles in my collection:

-Both twists handle 55-62gr bullets just fine. I can't perceive any differences in accuracy between them. With decent ammo both are more accurate than I am.

-1/7 is better suited for heavier 75/77gr bullets. While a couple of my 1/9 barrels can shoot heavier rounds well a couple of them can't. My observation is that this isn't brand specific. While a 1/9 barrel may handle 75/77gr bullets a 1/7 barrel will most certainly handle them.

-Proficiency and round placement is more important than barrel twist. A skilled operator with a 1/9, 1/10, or 1/12 barrel is certainly better off than a neophyte with a 1/7 tactical ninja rifle.

-People tend to defend what they own, despite being right or wrong.
Link Posted: 8/22/2005 2:41:14 PM EDT
[#5]
"Twist" is the term given to the distance within the barrel over which a rifled spiral completes one full revolution.  Specific twists are better suited to optimizing the flight of bullets of differing weights or types within the same caliber.

As an example, consider the .223 caliber (5.56 mm) bullet popular in both military and civilian applications.  A 1/12 twist (one revolution per twelve inches of barrel length) stabilizes 40 to 55-grain bullets well, but is unsuitable for heavier bullets like the 63-grain boat tail used in match target competition, or the 75-grain penetrator.  

Conversely, a 1/7 twist, suited to stabilizing the heavier bullets well,  is so rapid that it may cause potentially frangible bullets such as soft points to disintegrate while passing down the bore.  This makes accuracy erratic, unpredictable, and unsatisfactory for bullets other than FMJ and JHP.

A 1/9 twist in a 20- to 24-inch barrel allows for essentially the full range of bullet weights, 40 to 75 grains, as well as for the use of potentially frangible bullets.  Hence, it represents the ideal twist for this caliber because of its versatility.  A 16-inch barrel in the 1/9 twist will accurately launch all bullet types in weights up to 69 grains.

Most manufactures attempt to offer the public a barrel twist that will accommodate a wide variety of popular bullet weights associated with the generally recognized uses of a particular caliber.
Link Posted: 8/22/2005 2:49:11 PM EDT
[#6]
Get a 1 in 8.  It will stabilize ANY bullet the 1 in 7 will with the exception of the ultra long 90 grain match bullets, and it will NOT hurt any of the ultra thin jacket 45 grain lightweights.  

BTDT
Link Posted: 8/22/2005 2:56:01 PM EDT
[#7]

Quoted:
Get a 1 in 8.  It will stabilize ANY bullet the 1 in 7 will with the exception of the ultra long 90 grain match bullets, and it will NOT hurt any of the ultra thin jacket 45 grain lightweights.  

BTDT



+1...

I think most people would be best served by a high-quality 1/8 twist barrel. Accuracy is excellent and it digests a wide variety of bullet weights extremely well.
Link Posted: 8/22/2005 3:30:06 PM EDT
[#8]
In particular, I'm looking at the SEBR special that they have going right now.  It seems like a great price, but I don't want to buy a rifle that I can't use with lighter bullets.

Will I be ok with a 1x7 barrel and 55-grain FMJ rounds?  Is there even a reason to shootb lighter rounds?
Link Posted: 8/22/2005 3:37:45 PM EDT
[#9]

Quoted:
In particular, I'm looking at the SEBR special that they have going right now.  It seems like a great price, but I don't want to buy a rifle that I can't use with lighter bullets.

Will I be ok with a 1x7 barrel and 55-grain FMJ rounds?  Is there even a reason to shootb lighter rounds?

 

55s in a 1 x 7---- You're good to go.
I shot into Expert class with that setup-all the way to 600.
I know it's not optimum, but it worked ok.
Link Posted: 8/22/2005 3:39:59 PM EDT
[#10]

Quoted:
In particular, I'm looking at the SEBR special that they have going right now.  It seems like a great price, but I don't want to buy a rifle that I can't use with lighter bullets.

Will I be ok with a 1x7 barrel and 55-grain FMJ rounds?  Is there even a reason to shootb lighter rounds?


My primary range/training ammo is 55gr M193-and my 1/7 barrels shoot it just fine. As I said, there is no perceivable difference in accuracy in a 1/7 or 1/9 barrel using 55gr rounds.

That SEBR is a hell of a deal. If I needed another one I'd jump on it.
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