Bullet grains and BARREL twist???

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[ARCHIVED THREAD] - Bullet grains and BARREL twist???

Posted: 3/16/2006 4:12:09 PM EDT

Ok, so I have a 16" HBAR with a 1/9 twist on my AR. I have a good idea on what all this means but if someone could help explain this better to me that would be helpful. Maybe explain the different purposes different twists and bullet grains serve? IDK, whatever you think I should know. Much appreciated. -Lance

Posted: 3/16/2006 4:19:03 PM EDT

[#1]

hmmm...

...search...

TWIST.

Posted: 3/16/2006 4:31:55 PM EDT

[#2]

Quoted:
Ok, so I have a 16" HBAR with a 1/9 twist on my AR. I have a good idea on what all this means but if someone could help explain this better to me that would be helpful. Maybe explain the different purposes different twists and bullet grains serve? IDK, whatever you think I should know. Much appreciated. -Lance

Lance, you should do a search, but I'll give it in a nutshell.

1/9 twist will shoot anything 40gr to about 69gr.
1/7 twist will shoot anything from 55gr to 77gr.
1/8 is usually a match barrel (with match chamber) and is ideal for the 68-69 gr. stuff.

Posted: 3/16/2006 4:32:17 PM EDT

[#3]

Anything lighter than 70 grains will stabilize for sure. Anything above 75 grains will not. What's in between you have to test in yoru rifle. That's all there needs to be said on the subject.

Posted: 3/16/2006 4:32:50 PM EDT

[#4]

Quoted:
Quoted:
Ok, so I have a 16" HBAR with a 1/9 twist on my AR. I have a good idea on what all this means but if someone could help explain this better to me that would be helpful. Maybe explain the different purposes different twists and bullet grains serve? IDK, whatever you think I should know. Much appreciated. -Lance

Lance, you should do a search, but I'll give it in a nutshell.

1/9 twist will shoot anything 40gr to about 69gr.
1/7 twist will shoot anything from 55gr to 77 80 gr.
1/8 is usually a match barrel (with match chamber) and is ideal for the 68-69 80 gr. stuff.

Fixed it

Posted: 3/16/2006 4:42:59 PM EDT

[#5]

Quoted:
Quoted:
Ok, so I have a 16" HBAR with a 1/9 twist on my AR. I have a good idea on what all this means but if someone could help explain this better to me that would be helpful. Maybe explain the different purposes different twists and bullet grains serve? IDK, whatever you think I should know. Much appreciated. -Lance

Lance, you should do a search, but I'll give it in a nutshell.

1/9 twist will shoot anything 40gr to about 69gr.
1/7 twist will shoot anything from 55gr to 77gr.
1/8 is usually a match barrel (with match chamber) and is ideal for the 68-69 gr. stuff.

how do you tell what barrel(twist) you have?

Posted: 3/16/2006 4:44:15 PM EDT

[#6]

Quoted:
hmmm...

...search...

TWIST.

i have do that and this is what it comes up with

"No Topics Found"

Posted: 3/16/2006 4:44:57 PM EDT

[#7]

Quoted:
Quoted:
Anything lighter than 70 grains will stabilize for sure. Anything above 75 grains will not. What's in between you have to test in yoru rifle. That's all there needs to be said on the subject.

how do you tell what barrel(twist) you have?

"most" should have it stamped on the barrel somewhere...maybe under the handguards (1/7...1/9...etc.)

Posted: 3/16/2006 4:47:18 PM EDT

[#8]

Quoted:
Quoted:
hmmm...

...search...

TWIST.

i have do that and this is what it comes up with

"No Topics Found"

When I just searched "twist" this is what I got:

Forum Search Limited To 1000 Results (20 Pages) :: 105 Results Found :: Compiled In 5 Seconds

Posted: 3/16/2006 4:48:08 PM EDT

[#9]

Quoted:
Quoted:
hmmm...

...search...

TWIST.

i have do that and this is what it comes up with

"No Topics Found"

twist

AR15 board
30 days

pretty full page...

Posted: 3/16/2006 5:00:52 PM EDT

[#10]

you guys forget that you are team members and get more than like 30 days of search window

Posted: 3/16/2006 5:03:32 PM EDT

[#11]

My search was 30 days...to replicate a non-member search...

Posted: 3/16/2006 5:07:00 PM EDT

[#12]

Thanks fellas. You answered my question.

Posted: 3/16/2006 5:14:18 PM EDT

[#13]

Quoted:
you guys forget that you are team members and get more than like 30 days of search window

Sorry, my search was 3 months. I didn't realize that ~~cheap bastards~~ non team members only got 30 day searches.

Posted: 3/16/2006 5:20:38 PM EDT

[#14]

Quoted:
Quoted:
Quoted:
Anything lighter than 70 grains will stabilize for sure. Anything above 75 grains will not. What's in between you have to test in yoru rifle. That's all there needs to be said on the subject.

how do you tell what barrel(twist) you have?

"most" should have it stamped on the barrel somewhere...maybe under the handguards (1/7...1/9...etc.)

found it on top of my barrel right in front of the front sight...http://home.comcast.net/~hotairgypsy/DSC00076.JPG

Posted: 3/16/2006 5:30:46 PM EDT

[#15]

Quoted:
found it on top of my barrel right in front of the front sight...home.comcast.net/~hotairgypsy/DSC00076.JPG

Here's the decoder of what you have:

B = Bushmaster

MP = Magnetic Tested

5.56 NATO = 5.56 NATO chamber (a little looser than .223 SAAMI and WYLDE but can shoot milsurp ammo)

1/9 = 1 full twist in 9"

H BAR = Heavy Barrel profile (thick under the handguards).

Posted: 3/16/2006 5:52:27 PM EDT

[#16]

Quoted:
5.56 NATO = 5.56 NATO chamber (a little looser than .223 SAAMI and WYLDE but can shoot milsurp ammo).

So can the Wylde.

Posted: 3/16/2006 5:53:08 PM EDT

[#17]

Quoted:
Quoted:
Quoted:
Ok, so I have a 16" HBAR with a 1/9 twist on my AR. I have a good idea on what all this means but if someone could help explain this better to me that would be helpful. Maybe explain the different purposes different twists and bullet grains serve? IDK, whatever you think I should know. Much appreciated. -Lance

Lance, you should do a search, but I'll give it in a nutshell.

1/9 twist will shoot anything 40gr to about 69gr.
1/7 twist will shoot anything from 55gr to 77 80 90gr.
1/8 is usually a match barrel (with match chamber) and is ideal for the 68-69 80 gr. stuff.

Fixed it

Posted: 3/16/2006 5:56:23 PM EDT

[#18]

very cool...i have been wondering what the break down was....

Posted: 3/16/2006 5:57:13 PM EDT

[#19]

Quoted:
Quoted:
5.56 NATO = 5.56 NATO chamber (a little looser than .223 SAAMI and WYLDE but can shoot milsurp ammo).

So can the Wylde.

There's also better accuracy gained with the Wylde chamber compared to the 5.56 when using .223 ammo...

[ARCHIVED THREAD] - Bullet grains and BARREL twist???

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