doublegunshop.com - home Forums General Discussion Double Rifles, Paradox Guns & Gauge Rifles @ doublegunshop.com 16 bore conical, what twist?

I'm having a 16 bore double rifle built on a greener shotgun action and need advice on what twist rate I should have the barrels rifled for to shoot conicals. Any and all help would be appreciated.

If you know the weight and more importantly the length of the conical the Greenhill formula will tell you quite precisely. Here's a couple sites/calculators

http://www.titanreloading.com/ballistics-questions/greenhill-formula

http://www.z-hat.com/twistrate.htm

Thanks.

What did it tell you Mike? And I gotta see some pics of this beast when it's finished!! It sounds simply glorious!!!

I can't use the formula until I pick a mold and know the length of the bullet as well as the weight. I'm working on getting a mold chosen now.

Are you familiar with Accurate Molds? If not, here's a couple of his approximately 16 bore conicals. Tom has always been willing to cut whatever diameter I needed. These look too cool!!

http://accuratemolds.com/bullet_detail.php?bullet=67-600P-D.png

http://accuratemolds.com/bullet_detail.php?bullet=68-545A-D.png

http://accuratemolds.com/bullet_detail.php?bullet=66-500S-D.png

I like that first one. Using it with a diameter of.662 the formula says 1 in 82". How does that sound to the experts here?

Short doesn't require a lot of twist and I have the utmost confidence in the Greenhill formula. I can't remember the name of the Englishman who hunted India, wrote quite a bit, died young and recommended considerably slower twists than what we think of normal today for big bores. Of course he was shooting huge charges black powder, round balls or short conicals which figured into his equation. Anyway, 1-82 sounds like a good place to be to me, for that conical.

If you make a mistake,make it on the faster rather than slower side.
Mike

Mike, There used to be a gentlman out in the Sterling area that did a nice 20 bore DR conversion about 6-8 years ago. I might be able to dig up his name if you're interested.

Mike was it George Johnson or Cliff Hugg?

That would have been Mr Johnson!
He was getting kind of old back then so he might not be doing it anymore? He was a nice guy!

I went back and looked at the dates of when he was discussed,,, It was way over 10 years ago.

he had a stroke a few years back. He still makes the gunshows but I don't thinke he does much gunsmithing anymore. He lets me use his private rifle range when I need to.

I'm sorry to hear this. I was impressed with his skills based on the 20 ga.? bore rifle he did that I looked at.

Mike,
I have wanted to do that for a while.
Who is rifling the barrels for you?
What diameter is the bore vs grooves?
Who is maked the barrel blanks?

Thanks

Jerry

Mike,
I have wanted to do that for a while.
Who is rifling the barrels for you?
What diameter is the bore vs grooves?
Who made the barrel blanks?

Thanks

Jerry

Gerald John Taylor will be making the barrels for me. He will do them to your specs. I haven't decided on bore diameter and twist rate yet as I hav to choose a bullet/mold first.

John Taylor
Taylor Machine
14119 Military Road East
Puyallup, WA 98374
JohnTaylorMachine.com

16 bore is around .69 caliber. during the late unpleasantness, the yankee war mongers rifled several thousand model 1842 .69 calibler smooth bore muskets, in order to fire minie bullets at us rightous rebs. maybe some kind collector of such things would measure the twist rate for you and report his findings?

Uh ed,,, How long have you been in N.H.?

More than 6 months makes you a yankee. Deal with it!

ak: old saying:

"you can take the boy out of the south, but you cant take the south out of the boy"...