So is a 1 in 9 better than 1 in 8. Looking to load 160 grain Woodleigh`s and maybe 129 Hornady SST and 140 Hornady Interlocks. Should I worry about twist rate when I am selecting a 6.5x55 or does powder and other variables makes of the difference. Gun I looking for is more for big game and would like to load 160 grains.
Twist rate for 6.5x55. What is better? 1 in 8 or 1 in 9.
- Thread starter pbonura
- Start date
thunderstruck
Regular
- Location
- Northern B.C.
for the heavies go with 1:8 twist to keep your stability factor above 1.4.
With the assortment of top-quality 130-140 grain bullets available today, I fail to see the need for a 156/160 grain pill in the 6.5's.
Nevertheless, on the chance one may prefer to shoot the 156/160 grain bullets, the 1-8" twist is the best choice. [this also will stabilize those long 139/140 gr. match bullets]
I have had 6.5x55 rifle with 8", 8.5" and 9" twists. all worked well with hunting bullets up to 140 grains.
My present 6.5 rifles all have 8" twists. [ 260 Rem, 260AI, 6.5x55, 6.5x55AI ]
Regards, Eagleye
Nevertheless, on the chance one may prefer to shoot the 156/160 grain bullets, the 1-8" twist is the best choice. [this also will stabilize those long 139/140 gr. match bullets]
I have had 6.5x55 rifle with 8", 8.5" and 9" twists. all worked well with hunting bullets up to 140 grains.
My present 6.5 rifles all have 8" twists. [ 260 Rem, 260AI, 6.5x55, 6.5x55AI ]
Regards, Eagleye
tylerjwitty
CGN frequent flyer
- Location
- Northern Ontario
doubt you will see much difference but if you have a choice 1-8 unless you plan on making the barrel into more horsepower caliber
+1. 1-8 all the way.
1-9 will not stabilize the longer 140gr or 160gr bullets.
Mark
tylerjwitty
CGN frequent flyer
- Location
- Northern Ontario
yes it will. . i been there done that. but it will be handy if you might get bored and wish to make it into a 264 win mag
gunrunner8
CGN Ultra frequent flyer
- Location
- Kamloops, B.C.
The amount of misinformation you received is mind bogling! To stabilize the bullets in certain rifling twist only the lenght of bullet and speed is all that matters. Shooting 140gr VLD in short barreled 6,5-47 Lapua you might as well use 1-8" twist. The same bullet fired from 264WM in longer barrel will do just fine with 1-10" twist. 6,5x55 being in the middle of the pack will do OK with 1-9" twist IMHO.
tylerjwitty
CGN frequent flyer
- Location
- Northern Ontario
get the 1 in 8 simple answer
it such a open ended question its hard not to share knowledge to make the best educated purchase. .
it such a open ended question its hard not to share knowledge to make the best educated purchase. .
Woodleigh are 1.381 inches long. So you are saying this will work in a 1 in 9 twist. These are pretty long bullets. I think the information is pretty accurate but your point is valid. Length of bullets does matter. This load is pretty long. I think the 1 in 8 would be better for this long bullet. That will be my main 160 load for bear, moose.
The 1 in 9 twist has a 24 inch barrel and the 1 in 8 twist has a 22 7/8 barrel so they are almost the same length. Those are the two barrel lengths.
Making a .264 out of a 6.5x55 bolt gun also means opening the bolt face.
tylerjwitty
CGN frequent flyer
- Location
- Northern Ontario
personally i would't be shooting 160's out of a 6.5x55 but to each there own however ill state my reasoning..
* oal will have the bullet seated very deep into the case
*speed is very slow
but to each there own..
i found when i owned a 6.5x55 and a 260 rem that they both liked 120s
easy if you have a savage
gunrunner8
CGN Ultra frequent flyer
- Location
- Kamloops, B.C.
Even manufactures statements on bullet boxes are deceiving. Some of them (Sierra, Berger) are adviseing 1-8" twist for 6,5mm 140gr VLDs. This is bs. Those bullets should have minimum RPM asaigned to them instead. Somebody building say 6,5mm Whisper aka 6,5x223Rem, short barreled 6,5mm Carcano or something simmilar useing 1-8" twist with speeds not much more than 2000fps if that much will tumble those long, long bullets all the time every time. They need over 200 000 RPM to stabilize IMHO. Those same bullets at 3100fps from 1-10" twist in 264WM will have 223 200 RPM and will stabilize them nicelly.
tylerjwitty
CGN frequent flyer
- Location
- Northern Ontario
sounds about right. i was foolish when i got a 6.5 wsm made with a 1in 8 as soon as i started to crank the 140's up the accuraty went from 1/2 to 1 1/2 over spin isn't good either
You can't be sure that the loss of accuracy was due to "over spin". Some loads produce high MV, but poor accuracy.
A couple of other things (unrelated to that quote):
- bullets stable as they leave the muzzle tend to remain stable regardless of lowering velocity downrange, as their spin slows much less than their horizontal velocity; and
- often bullets defy what the tables and formula tell us. I have a 1:9 barrel that stabilizes 160's even at a MV of 2000 fps. It "almost" stabilizes a cast 170 at 1800 fps.
