measuring rifle twist?

[FrontierMuzzleloading]

Whats the correct way to figure out if I have a 1:48 or 1:66 twist? I tried doing a search on this but man, that was worse than trying to figure out myself as everything had some kind of way of doing it which never worked out for my rifle.

[WadePatton]

Measure it?

Here's what I'd do:

Load up a jag or tow worm tight enough that the rifling rotates the rod.  
Make a small mark or two on your rod.  
Measure the linear distance it takes (in or out) for 1/2 revolution.  
Multiply by 2, result is inches per revolution.  Twist rate.  


---
FTR, I had a "fast" twist TC and it shot plenty fine for deer hunting (I didn't save any targets, and didn't own it long).  BUT the guy I sold it to, decided that he HAD to get a slow twist bbl for it.  He did---without ever shooting the gun.  But he's happy with the gun, and that's what counts.

Just have to develop the best load regardless the twist.  I never inquired as to the twist Charlie put into my 30.  Decided to fully trust the decisions of the bbl makers on that point.  

[smokinbuck]

It's really pretty simple. Insert a rod with a tight enough patch that the rod rotates as it is inserted or withdrawn. With the rod bottomed out, mark the.
 top of the rod with a magic marker, tape or some other way to identify the area as the top center and the same at the muzzle. Withdraw the rod until your mark is at the bottom and mark the rod at the muzzle. If the difference in the muzzle marking is 24" and the rod has turned 1/2 turn then your ROT is 1-48. I use 24" only as an example, it can and will vary from barrel to barrel.
Mark

[Dphariss]

Need  tight patch, a jag that is firmly fixed to the rod and a rod with a BEARING HANDLE.
Slow twist ML barrels may need to be checked by using the 1/2 turn method.

Dan

PS Patch should be oiled.

[D. Taylor Sapergia]

As an indicator, I place a piece of masking tape around the rod with a 'flag' sticking straight up.  It is easy then to see when the rod will have made 1/4 or 1/2 of a revolution.

[FrontierMuzzleloading]

thanks guys. The info I was getting on google was to do a complete turn 

[WadePatton]

Yeah, that's a crappy resource for much specialized information. 

Full turn works for moderns where the projectile makes a full revolution or two in the bore.  Sometimes we gotta do some maffammatics. 

[FrontierMuzzleloading]

26x2=52 so I'd assume that its a 1:48 with deep rifling.

[Daryl]

A little slippage or perhaps it actually is a 52 - or anything between about 46 and 52?  If it's a deep grooved barrel, it isn't buttoned.
Oft times in button'd barrels, the button will slide a bit, slowing the twist.  I expect that would not be a high priced barrel for a ML, more likely a production barrel like some we saw in the 70's and 80's. 

One barrel maker told me he could 'influence' the rate of twist by 1", either way from it's actual rate while the button was traveling through the tube.  I asked if you could 'influence' it for the last 2 or 3" only, and he thought he could - money being as it was then, I didn't get around to ordering one from him, but the concept is interesting. Hmmmm. He retired before I could order that 'zinger' of a barrel.

[FrontierMuzzleloading]

Its a CVA barrel so I probably just got a little slippage.  1:48 is normal. The rifling depth though is a lot deeper than any of the other Hawken barrels I've worked with. This one is from 86-88 year so there could be some difference in the depth compared to the others I've worked with.