HKPRO Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
1,921 Posts
Discussion Starter #1
anyone know the standard barrel 91 twist rate?
 

·
Registered
Joined
·
110 Posts
twist

I think my 911 is one in 11? metric versus inches? bob
 

·
Premium Member
Joined
·
8,625 Posts
I think my 911 is one in 11? metric versus inches? bob
I don't know if it's 1 in 11 or not, but it's definitely not a metric vs. inches issure. There are 2.54cm per inch, or 25.4 mm per inch. Nothing that would get you to 1 in 11 anything that is equivalent to 1 in 12".
 

·
Registered
Joined
·
110 Posts
twist

in reality I was being courteous to the senior members here as my memory is fine but we can all be wrong. on page 35 of my 911 owners manual it states that the rifling is conventional 1 in 11 twist. IK date code. is this in error from h&k? did they change the twist rate versus older g3/91 guns? what is the difference in bullet stability versus bullet weights that will stabilize in a 1 in 12 versus 1 in 11 rate. those questions were why I was following the thread.
 

·
Registered
Joined
·
887 Posts
The 91 has the same barrel characteristics as the G3. That makes it a 4 groove RH 1 in 12 twist rate which is the 'ideal' twist rate for rifles using the .308 Winchester round. Works for me.
 

·
Registered
Joined
·
110 Posts
twist rate

so my h&k manual is wrong? 1989 91(911)
 

·
Premium Member
Joined
·
8,625 Posts
How would you do that....Accurately?
Get a cleaning rod with a rotating handle (as most of them are), some patches, a marks-a-lot, and a ruler. Put a really tight patch onto the patch attachment and push it a few inches into the muzzle. If the patch is tight enough, the rod will rotate along with the rifling. Now draw a line around the cleaning rod right at the muzzle, and a line on the muzzle face itself that continues down the cleaning rod. Now from about 10" to about 13" up the cleaning rod, in the same orientation as the mark on the muzzle, draw another line on the side of the cleaning rod. Now just push the rod into the muzzle. Push it in until the second line on the rod aligns with the mark on the muzzle, meaning that it's made one revolution. Now mark a second circle on the cleaning rod and pull it out (or push it completely through, then remove your patch, then pull it back out.)

Now just measure the distance between the two circles around the cleaning rod and you'll get the full twist distance.

It takes a lot of text to explain it, but once you do it it's pretty easy to understand.
 
1 - 11 of 11 Posts
Top