is a 45 colt lever with 1:16 twist too fast?
Forum rules
Welcome to the Leverguns.Com General Discussions Forum. This is a high-class place so act respectable. We discuss most anything here other than politics... politely.
Please post political post in the new Politics forum.
Welcome to the Leverguns.Com General Discussions Forum. This is a high-class place so act respectable. We discuss most anything here other than politics... politely.
Please post political post in the new Politics forum.
is a 45 colt lever with 1:16 twist too fast?
This is a pretty fast twist for a lever action. Any guesses would it overstabilise 200-220 grain bullets if pushed 1400-1500fps or would it be okay? I know there is some kind of formula to do it, but can't recall it
Re: is a 45 colt lever with 1:16 twist too fast?
The Greenhill formula is what you're thinking of.
Here's a calculator: https://www.vcalc.com/wiki/AndrewBudd/G ... Twist+Rate
At those velocities with the bullets typically fired in these guns, I can't see it "over-stabilizing".
Here's a calculator: https://www.vcalc.com/wiki/AndrewBudd/G ... Twist+Rate
At those velocities with the bullets typically fired in these guns, I can't see it "over-stabilizing".
- AJMD429
- Posting leader...
- Posts: 32161
- Joined: Sun Sep 09, 2007 10:03 am
- Location: Hoosierland
- Contact:
Re: is a 45 colt lever with 1:16 twist too fast?
For larger bores some say the 'Dell' formula is better - it is on the LASC website but I can't find it right now.
Here's an article from there on the 444 and twist that might lead to it if you snoop around. Lots of good information there anyway.
http://www.lasc.us/Fryxell444Marlin.htm
Here's an article from there on the 444 and twist that might lead to it if you snoop around. Lots of good information there anyway.
http://www.lasc.us/Fryxell444Marlin.htm
Doctors for Sensible Gun Laws
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.
Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.
Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
Re: is a 45 colt lever with 1:16 twist too fast?
.
What .45 Colt levergun has a 1:16" twist ?
I know all Rossi's have a 1:30" twist, Miroku/Winchester 92's have a 1:26", and Marlin 1894's a 1:38" twist, so inquiring minds would like to know...
.
What .45 Colt levergun has a 1:16" twist ?
I know all Rossi's have a 1:30" twist, Miroku/Winchester 92's have a 1:26", and Marlin 1894's a 1:38" twist, so inquiring minds would like to know...
.
Re: is a 45 colt lever with 1:16 twist too fast?
Pete, marlin used to list 1:16 for their 1894. https://www.marlinowners.com/forum/1894 ... -colt.html Not sure how long ago this was or whether it was a long running typo error by the company, but I found one for sale, where the fella says his is the 1:16 twist. | I liked the sound of it for potential accuracy with very low velocity loads, but not sure how it will do when pushed a few hundred fps faster.
I cant make sense of the greenhill formula page, I change velocity but it doesn't change the answer, though it should I'd imagine?
I cant make sense of the greenhill formula page, I change velocity but it doesn't change the answer, though it should I'd imagine?
Re: is a 45 colt lever with 1:16 twist too fast?
My Win 94AE is a 1-16 twist.
- AJMD429
- Posting leader...
- Posts: 32161
- Joined: Sun Sep 09, 2007 10:03 am
- Location: Hoosierland
- Contact:
Re: is a 45 colt lever with 1:16 twist too fast?
As I understand it, it's essentially sort of a gyroscopic phenomenon, with the main factors being the length versus diameter of the projectile, and the rate of spinning necessary to stabilize it being faster the longer it is. Think of a bicycle wheel traveling through space in the direction parallel to its axle. If there were no air to interfere with things, it would not have to be spinning very fast to have quite a bit of gyroscopic stabilization against yaw. On the other hand if the object were a pencil traveling along its axis, it would have to be spinning extremely rapidly to have stabilization against yaw.
The 'only' thing the rifling twist has to do with it is that is sets the revolutions-per-foot. But what matters is revolutions-per-second, so multiplying by feet-per-second gives that. So you are right. Velocity DOES matter.
A bullet going 1,000 fps down a 1:12" twist barrel will wind up spinning 1,000 revolutions per second, or 60,000 rpm. So would a bullet going 2,000 fps down a 1:24" twist barrel, or 500 fps down a 1:6" barrel. Practical limitations in bullet toughness and pressure tolerance limit all the options a bit of course, so 100 fps in a 1:1.2" isn't likely to happen, nor 10,000 fps in a 1:120" barrel.
Anyhow, the formulas basically use bullet shape to predict necessary rpm, then the limits of your gun and cartridge (or subsonic goals) will set your velocity. Based on whatever velocity you will be using, there will be a necessary twist to get the rpm you need.
I can't find the Dell modification of the Greenhill formula, but they both work that way.
Last edited by AJMD429 on Mon Jun 21, 2021 10:31 pm, edited 1 time in total.
Doctors for Sensible Gun Laws
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.
Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.
Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
Re: is a 45 colt lever with 1:16 twist too fast?
Yes as I thought Doc, and thanks to cnjarvis for posting the link. The problem is with the link is for example I plug in 900fps and all the other specs and it comes to a certain twist recommendation. Then I plug in 1500fps with everything else equal, but it doesn't change the twist recommendation, its the same as for 900fps. Either my browser is having a glitch and not updating the data, or the formula is having the glitch.
Looking at the written formula ( and keeping in mind my algebra is real rusty) he has a variable 'C' (which he doesn't define in the blurb, what is it?) but mentions 'V' for velocity, but there is no 'V' in his formula! Something is gooned up here, or I could be too dumb to understand it
Looking at the written formula ( and keeping in mind my algebra is real rusty) he has a variable 'C' (which he doesn't define in the blurb, what is it?) but mentions 'V' for velocity, but there is no 'V' in his formula! Something is gooned up here, or I could be too dumb to understand it
Re: is a 45 colt lever with 1:16 twist too fast?
I found this calculator too http://kwk.us/twist.html
- marlinman93
- Advanced Levergunner
- Posts: 6473
- Joined: Sun Apr 01, 2007 3:40 pm
- Location: Oregon
Re: is a 45 colt lever with 1:16 twist too fast?
There are other things to consider with twist rate that can affect accuracy. Think of it like a car accelerating into a corner at say 60 mph, and the corner being a 20 degree turn. Then the same speed and car coming into a 90 degree curve. There's a point when the tires break loose, and the car loses control. The bullet jumping into the rifling with a proper twist rate engages the rifling fine, and the rifling engraves on the bullet to spin it, and stabilize it as it exits the barrel. But make that twist rate too fast and the bullet slams into the rifling that has too much twist and the bullet will begin to deform as it hits too much angle on the fast twist rate. Might not be as bad with a jacketed bullet as it is with cast. But either will not like entering a twist rate that's too fast anymore than a car going too fast into that 90 degree corner. It wont allow the bullet to get properly engraved into the rifling, and only slowing it down will do so. The more you slow it down, the better it will engrave the rifling. But then you end up with a gun to plink with, and not a gun that can be used well at normal velocities.
Pre WWI Marlins and Singleshot rifles!
http://members.tripod.com/~OregonArmsCollectors/
http://members.tripod.com/~OregonArmsCollectors/
Re: is a 45 colt lever with 1:16 twist too fast?
I agree !
I have found that it is hard to over spin a bullet unless you are pushing laser velocities. Very easy to not spin them fast enough. My 1 : 16 twist 44 works with a 300 gr bullet at 750 to 1600 fps without over spinning them at the higher end. Accuracy is just as good at both ends of the spectrum. I cannot see different results with a 45 cal. bullet. As long as the bullet is sized properly to the barrel
Gettin old ain't for sissies!
There just has to be dogs in heaven !
There just has to be dogs in heaven !
Re: is a 45 colt lever with 1:16 twist too fast?
Re: is a 45 colt lever with 1:16 twist too fast?
.
Last edited by Pete44ru on Thu Jun 06, 2019 7:38 pm, edited 1 time in total.
- J Miller
- Member Emeritus
- Posts: 14885
- Joined: Sat Mar 31, 2007 7:46 pm
- Location: Not in IL no more ... :)
Re: is a 45 colt lever with 1:16 twist too fast?
Boy am I confused.
I have a 1985 vintage Win 94AE and a 2005 vintage Marlin 1894 Cowboy both in .45 Colt and both have the 1:38 twist.
I've read the thread linked to the Marlin forum and all the posts here and it seems there is a variation to what is out there.
I wonder if some barrels were rifled with a different twist than the norm.
Joe
I have a 1985 vintage Win 94AE and a 2005 vintage Marlin 1894 Cowboy both in .45 Colt and both have the 1:38 twist.
I've read the thread linked to the Marlin forum and all the posts here and it seems there is a variation to what is out there.
I wonder if some barrels were rifled with a different twist than the norm.
Joe
***Be sneaky, get closer, bust the cap on him when you can put the ball where it counts .***
Re: is a 45 colt lever with 1:16 twist too fast?
.
Maybe this will act as a de-fogger...…
45 Colt - 1 in 16" .....Chiappa M92; Ruger; T/C Carbine
45 Colt - 1 in 26"......Win 92
45 Colt - 1 in 38"....Henry Big Boy; Marlin; Ruger; Win 94
.
Maybe this will act as a de-fogger...…
45 Colt - 1 in 16" .....Chiappa M92; Ruger; T/C Carbine
45 Colt - 1 in 26"......Win 92
45 Colt - 1 in 38"....Henry Big Boy; Marlin; Ruger; Win 94
.
- J Miller
- Member Emeritus
- Posts: 14885
- Joined: Sat Mar 31, 2007 7:46 pm
- Location: Not in IL no more ... :)
Re: is a 45 colt lever with 1:16 twist too fast?
Yes that helps. Now if one was to acquire a carbine from each maker and test the various loads to see how they work with the different twists, I'd bet the results might be surprising. Or not.
Joe
***Be sneaky, get closer, bust the cap on him when you can put the ball where it counts .***
- AJMD429
- Posting leader...
- Posts: 32161
- Joined: Sun Sep 09, 2007 10:03 am
- Location: Hoosierland
- Contact:
Re: is a 45 colt lever with 1:16 twist too fast?
Interesting - I think it is similar with 44 Mag. The Rugers (96/44 levergun as well as 77/44 bolt action and I believe the semiauto as well) also have a faster (1:20) twist in 44 Mag - a good deal faster than the more traditional leverguns.
Doctors for Sensible Gun Laws
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.
Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
"first do no harm" - gun control LAWS lead to far more deaths than 'easy access' ever could.
Want REAL change? . . . . . "Boortz/Nugent in 2012 . . . ! "
Re: is a 45 colt lever with 1:16 twist too fast?
The subject of overstabilization is complex, and you'll find many complicated explanations of what happens. The one thing all of them will agree on, though, is that if it plays any significant role it is only at extreme ranges -- 500 yards or more. I seriously doubt that means anything at all to someone using a .45 Colt-chambered carbine.
Re: is a 45 colt lever with 1:16 twist too fast?
44 Special - 1 in 16".....Colt DA
44 Special - 1 in 18"....Charter Arms
44 Special - 1 in 20"....Chiappa M92; Colt SAA; S&W
44 Magnum - 1 in 14"....MOA
44 Magnum - 1 in 16"....Win 94
44 Magnum - 1 in 18"....AutoMag; Magnum Research Desert Eagle; Merrill; RPM
44 Magnum - 1 in 20" ... Abiline; Cimmaron; Freedom Arms; Ruger 96; T/C Carbine
44 Magnum - 1 in 22"....T/C
44 Magnum - 1 in 30"...Rossi 92
44 Magnum - 1 in 38" ...Henry Big Boy; Ruger Carbine; Marlin 336, 1894; Rem 788; Win 94; Browning 92
.