.40 caliber, which contour?

[gard72977]

I really liked the FCI sight. I will talk with the builder and ultimately go with his advice but I like to have my ducks in a row when I start. Its a Soddy Daisy gun so the 40 is correct but a 44 is really appealing for a all around match gun. Will have to see how this plays out with the amount of taper and weight of barrel. Since I have my choice of length Im thinking 47"

 

[M. De Land]

I had the forty itch for a spell and finally after looking over ball weights decide on a .45 instead, never have regretted it either. Mike D.

 

[Hefner]

In the early 1980's I built a .40 Hawken with a 34"x1" Douglas barrel. It weighed 10 1/2 pounds.
I shot a 48xxx on the 6-bull at 50 yards at the Fall Shoot at Friendship. In 1987, my 15 year old son, shot a 50xx off the bench at 50 yards on his way to the AZ State Junior ML Championship. It is heavy but feels well balanced to me, even after all these years.

 

[Blackbruin]

Jason will make a 46" .40 a weight not just a b or c. Mine is due shortly for lehigh.

 

[woody3694]

i have 40 cal with douglas supreme barrel. great shooter.

 

[gard72977]

i have 40 cal with douglas supreme barrel. great shooter.

Don't just tell us about it. Post a pic!!!!

 

[glrerun]

WOW there is a lot of good information on barrels here. I want to learn more about barrels, rate of twist, how many grooves, choosing a length, etc.

What is the best way to learn? are there any good books? formulas?

 

[Wes/Tex]

I know there are formulas out there but always went with the "ooh, I like that" formula! There's a lot of opinions about what's best but I've been pretty successful with 1-48" to 1-70" for ball and have kept with that. Chunked my share of Minies and Maxis years ago but have become a PRB guy who leans toward longer and tapered or swamped for barrel. Since my eyes started giving me trouble, I've gone to smooth fowlers...cuts down on the having to remember part! :wink: :thumbsup:

 

[Pete G]

I've built two forties. One with a 42" A weight swamped GM and the other with a 42" 13/16" straight with a 1/16" taper draw filed in to replicate a late period flint profile (I won't do that again). Based on that experience, if I ever build another 40 I would go with at least a 42" B weight or a 38" C weight.

 

[galamb]

If you like formula then Greenhill can help you pick the twist.

The "modified" Greenhill says caliber x 1.25 is "about right".

So for the 40 cal (40 x 1.25 = 50), so the "commercially typical" 1:48 would be a safe bet.

If you want to shoot conicals you generally go for shallower rifling (like maybe .004"), for roundball you get numbers like .010 - .012 kicked around in this caliber.

As has been noted - NOBODY agrees on what is best and even the barrel makers have different ideas.

Here's a chart of some 40 cal tests (I believe Zonie might have posted it up a good while back).

It shows the velocity differences with different barrel lengths using the same powder charge.

So for you performance seekers, in this caliber at least, size (length) "matters" :rotf:

 

[jamesthomas]

It looks too me that some of those numbers are mixed up. you get a jump from 34" at 1610fps to 1735fps for 36". and then you have 26" inches at 1596fps with 28" at 1523fps. There are a couple of other mistakes on that chart also. It looks to me that somebody had a few beers when they wrote down those numbers.

 

[azmntman]

or maybe when they were cutting the barrel?

 

[galamb]

No, the "1523" should have been "1623" (I am guessing) and 1610 should be 1710 - that would put it all in order.

 

[Zonie]

The only error in the table is the value given for the 28 inch length.

The 1523 fps should have been 1623 fps.

Beyond that, for any questions about the velocities shown you'll have to ask Turner Kirkland. :rotf:

I will admit the 1610 looks suspicious. Bet it should have been 1670 but the publisher mis-read it.

 

[galamb]

Whether the numbers are a little out of whack, or non-linear or only applicable when the moon is half full, at the end of the day, regardless of barrel maker or caliber the "tests" show that all else being equal, a longer barrel will increase velocity.

Which means "squat" unless you care about velocity.

An arrow from my bow traveling about 280 fps gets to bambi before he can move enough for me to miss.

So whether my roundball is travelling 1500 or 1700 fps it makes little difference.

Most BP calibers do not develop enough ft/lbs to kill by shock so you are relying on shot placement - so again, whether it takes .1 seconds to get to target or .088 @ 50 yards(which is blistering compared to the .22 seconds for my arrow to travel 30 yards), it kinda don't really matter.

 

[gard72977]

Barrel has been ordered. It is a 40.5" straight taper 15/16 to 7/8 with a 1/57 twist. I chose to start with a 15/16 for a good ram rod clearance. The rifle will come out a little heavy but it is a target rifle so it does not matter. Charles Burton recommended going with a taper barrel for accuracy. It works with my rifle so this part is done. Just have to wait a year for the rifle to be started.

I went with the 1/57 so I could shoot a little stronger load. I know it does not make a lot of difference but a few more pounds of knock down power is real important when you are on the anemic side. I will be shooting Swiss 3F and hoping to do ok on the steel targets. My match gun is a 54 but I would like to be able to take the 40 and have some fun.

This Soddy gun is my favorite of all muzzleloaders. Just want to be able to shoot it my local club events. You club may be different but a 40 has some trouble knocking down the targets at mine.

 

[vulture]

It is interesting to listen to you folks talk about the "long" rifles and "small" calibers that you use and enjoy. Living where I do the smallest caliber I have ever seen or heard of someone using is .45, and most are .50 - .58, and of the plains rifle configuration, half stock with barrels much shorter than you folks are using, something in the range of 28 - 36 inch. I have a Leman fullstock in .50 that I built some years ago and it has a 38" straight octagon 15/16ths barrel and it is very muzzle heavy, at least I think it is compared to my two .54 of the same design but with 34" barrels. Maybe I will have to look into a "long" rifle with a smaller bore some day, right now I'm trying to put together a Lyman GPR kit in .54 flint and making some modifications along the way. I replaced the original lock with one from L&R, added a Davis replacement trigger, and am waiting for a fully inlet replacment fullstock from TOW for it. When I get through it will cost me as much as just buying all custom parts, but this is the way I wanted to do it. I love looking at the pictures of the rifles you folks own and shoot.