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RH vs LH twist for accuracy

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17 September 2009, 04:56
VFR1
RH vs LH twist for accuracy
Is there any inherent difference in accuracy between RH and LH twist barrels in rifles? Thanks, Bob
17 September 2009, 05:22
enfieldspares
No. The difference exists because of theories about the rifle "screwing in" to the firer's shoulder when being fired and/or "unscrewing" the barrel from the receiver!
17 September 2009, 13:58
muzza
maybe its for Northern Hemisphere vs Southern Hemisphere - like the way the water spirals as it goes down the drain in the sink...


________________________

Old enough to know better
17 September 2009, 16:46
VFR1
So for most African hunting, LH twist would be preferable Wink
17 September 2009, 18:57
Jim Kobe
It is called the "correolis" effect.

You need two rifles, a RH twist when hunting in the northern hemisphere and a LH twist for the southern. bsflag


Jim Kobe
10841 Oxborough Ave So
Bloomington MN 55437
952.884.6031
Professional member American Custom Gunmakers Guild

18 September 2009, 13:06
muzza
And a smooth-bore when standing on the Equator stir


________________________

Old enough to know better
19 September 2009, 04:08
Duane Wiebe
A LH twist tends to unscrew your cleaning rod tips
19 September 2009, 07:28
Les Staley
I was going to break in here with some smart ass remark, but I can see youse guys already beat me to 'em... Les
19 September 2009, 18:53
Rojelio
quote:
Originally posted by Duane Wiebe:
A LH twist tends to unscrew your cleaning rod tips


Only if you clean from the muzzle. Big Grin

Rojelio
19 September 2009, 19:27
Jim Kobe
quote:
Originally posted by Rojelio:
quote:
Originally posted by Duane Wiebe:
A LH twist tends to unscrew your cleaning rod tips


Only if you clean from the muzzle. Big Grin

Rojelio


I hope you are not serious in Making that remark


Jim Kobe
10841 Oxborough Ave So
Bloomington MN 55437
952.884.6031
Professional member American Custom Gunmakers Guild

19 September 2009, 21:50
Rojelio
quote:
Originally posted by Jim Kobe:
quote:
Originally posted by Rojelio:
quote:
Originally posted by Duane Wiebe:
A LH twist tends to unscrew your cleaning rod tips


Only if you clean from the muzzle. Big Grin

Rojelio


I hope you are not serious in Making that remark


Hey Jim, look again. Big Grin
20 September 2009, 12:44
Lincs Stalker
Always thought that the "correolis" effect can't be helped in a single barrel rifles, but a double might benefit from one 1x RH & 1 XLH twist. Not at dangerous game distance but in a lighter rifle for plains game.
20 September 2009, 12:52
Wm.S.Ladd
quote:
Originally posted by muzza:
maybe its for Northern Hemisphere vs Southern Hemisphere - like the way the water spirals as it goes down the drain in the sink...


The water down the drain is a wive's tale.
20 September 2009, 13:59
303Guy
Does anyone know why a L/H or R/H twist is chosen? (It sure does unscrew a cleaning brush!)


Regards
303Guy
20 September 2009, 14:48
Alan W
Here is a curious observation from left hand target shooters (myself included) and rt hand twists.

With a good solid wind zero at short range(300 yds) our zero shifts left from 1/2 min to up to 1 to 1.25 min at 1000. Ive asked many of my rt hand customers about this and none seem to encounter this.

Always have wanted to screw on LH twist barrels for them to enjoy the bitching and head scratching!

Alan Warner
20 September 2009, 15:49
hawkins
Now I understand why there are so many different twists available. They are for shooting in
different directions.
Good luck!
20 September 2009, 18:39
J.D.Steele
The bullet's rotation will alter & actually curve its flight path at long range, curving to either the right or left depending upon the direction of twist. This flight path alteration is completely independent of the coriolis force that affects storms and drains in each hemisphere, as I'm sure the jokesters already know.

I first observed this behavior back in the '60s on the 600-yd range at Trinidad and further evidence can be found by examining the open rear sights on any 1903 Springfield or 1884/1888 Springfield trapdoor. You'll note that the sight's track is angled to one side as the range increases, to correct for the right-hand twist. The US Army Ordnance Dept spent much time experimenting to find the right compensation angle, and it's remarkable how close the sights are calibrated when the proper bullet and load is used.

No difference in accuracy, IMO the only difference is in POI at extended range.
Regards, Joe


__________________________
You can lead a human to logic but you can't make him think.
NRA Life since 1976. God bless America!
20 September 2009, 19:27
Alan W
Joe:
Well documented and available for all to read. Good post.
What I was getting at is I think because a rt. twist bbl. torques into the face of a rt. hand shooter and out on a lefty there is greater mechanical structure to hold the shot through barrel time, thus less wind zero deviation.

I think I read somewhere that Pope would build a barrel twist to match the shooters hand.
22 September 2009, 09:06
Allan DeGroot
There is a tendency for bullets from a Right hand twist to rise in a right to left crosswind and drom in a left to right crosswind but as I recall the effect at 200yards ammounted to something like 0.008"

The opposite can said to be true about left hand twists
in the same crosswind.

In a pistol it makes a difference because on handguns like say.. a 45ACP torquing of the handgun is far more noticeable.

I was subjected to a blind test of left and right hand twist barrels in a 1911 and I could pick the right hand twist barrel easily... the RH twist twists into our hand, the LH twist tries to twist out (for a right handed shooter)

It was enough of a difference that when I bought barrels from BarSto and they asked left or right twist I had no doubt I wanted the RH twists.

for a rifle? for real world purposes? I doubt it makes damn bit of difference.


AD


If I provoke you into thinking then I've done my good deed for the day!
Those who manage to provoke themselves into other activities have only themselves to blame.

*We Band of 45-70er's*

35 year Life Member of the NRA

NRA Life Member since 1984
22 September 2009, 13:23
muzza
If you want to see how much your bullets deviate from the mythical straight line-of-sight - fire a few tracers in dim light conditions.

Wm.S.Ladd , sir - you obviously have little sense of fun in life to have made so bold a statement
quote:
The water down the drain is a wive's tale.


My wive just told me that our Southern Hemisphere water spirals in a clockwise direction so it must be true....


________________________

Old enough to know better
22 September 2009, 16:10
enfieldspares
The northern and southern hemisphere argument is a nonsense as Britain had in the 20th Century and Empire that not only spanned BOTH but some groups of colonies that straddled the Equator too!
22 September 2009, 19:35
J.D.Steele
I don't know about toilet bowls, but IIRC it's my impression that cyclones/hurricanes/typhoons rotate in different directions in the Northern vs Southern hemispheres and that these storms never actually cross the equator but rather will always move away from it, due to their spin as compared to and affected by the Earth's rotation. It's actually physics, and fairly basic Physics 101 at that.

But, like Lacey J (Dalton) said in the song, "I've been wrong before!" Perhaps some more-experienced geographer can enlighten us?
Regards, Joe


__________________________
You can lead a human to logic but you can't make him think.
NRA Life since 1976. God bless America!
22 September 2009, 19:44
butchlambert
Muzza,
You better listen to your wives. Stuart Elliott sent me a short video of his crapper flushing in a different direction. He lives in Queensland.
Butch
23 September 2009, 04:43
muzza
Crikey Butch - how long have they had flushing toilets in Australia???? Must be a recent innovation .... Wink


________________________

Old enough to know better
23 September 2009, 08:53
butchlambert
Muzza,
Stuart was probably visiting a Kiwi when the photo was made.
Butch