21 January 2010

Underhammer barrelmaker? Is there even such a thing?

Well friends, the regular hunting seasons are over and the guns are all cleaned and put up for the winter. But beware - Cupid is already gathering arrows in preparation for a hunting season all his own. Yes, it’ll soon be that time of the year when a man’s fancy turns from hunting to other endeavors that some would call “matters of the heart.” It’s amazing just how powerful that almost primal urge is that can render an otherwise sound mind into mere mush and cause a grown man to revert into a fidgety boy having just one thing on his mind…

...building another rifle for the fall hunting season.

What did you think we were talking about?

Like other muzzleloader builders, we underhammer makers are always looking for a source of good barrels. Luckily, today’s builders do have a good supply of barrels from which to choose for making tomorrow’s family heirlooms.

That is, most muzzleloader builders have a good supply of barrels.

Those of you who have requested Captain James Forsyth’s wonderful book, The Sporting Rifle and its Projectiles, have learned of the many advantages of Forsyth rifling. As a result, some of you now wish to build a big-bore rifle based upon the ideas expounded by Forsyth and proven by those of us who shoot such rifles.

Tah dah!!!

Yup, you guessed it. Time, once again, for my annual plug for Forsyth rifling in big-bores.

Since my first posting of the Forsyth information on this blog, I’ve received many queries seeking a source of Forsyth barrels as it would seem that they are not readily available. Unfortunately, the source that had provided me with virtually all the Forsyth barrels I used through the years has locked his shop, retired, and gone fishing. So I, too, have been looking for another barrel maker who can provide those special barrels that have made me a believer in the big round ball as being The Best muzzleloading projectile for the taking of big, tough game with one shot.

Now, I know them’s fightin' words for some hunters, but that’s only because they haven’t yet discovered how much better big round balls really are over those plastic-wrapped little pills they have been convinced will do a better job! The fact is that you just can’t begin to imagine how effective big round balls are on big game until you’ve hunted with them. It’s that simple.

Some may protest and argue that I probably haven’t yet tried the new sub-calibre bullets wrapped in the latest version of a plastic cocoon. And while that’s true, as I haven't,  I have made a few underhammer rifles with the fast twist for my Forsyth customers who wanted to give the new notion a try. They have each come back to hunting with big round balls. Their curiosity satisfied, they had to agree, too, that Forsyth had this muzzleloading hunting formula all figured out 150 years ago. I trust their opinions and won’t waste my time on sub-caliber plastic-wrapped bullets. Besides, I have plenty of experience with cartridges that shoot the equivalent of the new breed of muzzleloading projectiles and loads and in my humble opinion they can’t hold a candle to Forsyth performance.

Recently I have contacted several barrel makers who have indicated that while they may not list slow twist, shallow rifling options on their price lists, they are willing to make barrels with the magic Forsyth rifling for those of us who request it. However, they ask that the rifle builder provide the exact rifling specs he requires and they will then make the barrel to order.

For those of you who have not read Forsyth’s book, or if you did, but still didn’t catch on to his sometimes subtle suggestions of dimensions, here is a formula that I have used that has proven very effective in nearly two hundred rifles in which I had employed it.

To begin with, however, it must be understood that the advantages of the extreme performance capabilities rendered by the Forsyth rifling system are only obtainable in big calibres with .58 being the smallest bore advised. Smaller diameter balls just don’t have enough mass to provide the wrecking ball blow needed to anchor and kill big game with just one shot.

That said we can now get to the Magic Formula.

Most muzzleloading barrels wear deep grooves of depths of .012” to .016” (that’s thousandths of an inch) with land width being about equal to that of the grooves. Forsyth, on the other hand, calls out a groove depth of only .005 of an inch. The groove to land width ratio should be a minimum of 5:1 and more is better.The shallow grooves allow less blow-by of the propelling gas thus making more efficient use of the powder charge.

The next aspect of the formula is the slow twist. This is based upon the fact that the round ball is a perfect geometric form and as such requires very little rotational spin to stabilize it in flight. Another fact is that the larger the round ball, the less spin is needed to keep it tracking straight to the target.

While Forsyth prefers a rate of twist of 1 turn in 144 inches, I have experimented, too, and learned that a twist of 1:108 will provide all the benefits of the upper end of the performance spectrum, but provides sufficient stabilization of the big round ball when loaded to velocities much lower than the 1900 – 2000 feet per second that we normally achieve from the Zephyr and Faeton rifles.

If you’re not really sure what rifling specs you need, feel free to drop me a line and I’ll be happy to help you figure it out for your calibre with specs you can then give to the barrel maker of your choice.

Shown above is the muzzle of a beautiful custom 12-bore barrel made for me by gunsmith, John Taylor. This barrel is made of “hard steel” as Forsyth would say, and utilizes an 8.5:1 groove to land ratio with very narrow lands of only .040” width. Clicking on the center of the photo will provide a real close-up view of the lands at the muzzle and display the extreme width of the grooves. Click the Back arrow to return to the text.

According to Forsyth’s thinking, the idea is to have as little of the land bearing against the ball as possible – hence narrow lands. Forsyth rifling does not require a hammer tight fit of bullet to the rifling. The influence of the slow twist on the patched ball is so gentle that the ball does not resist the guidance of the rifling. This allows us to achieve high velocity without the worry that the ball will strip from the patch and render a wild shot. This also allows easy loading without the need of extra gadgets such as a short starter.

As an additional side benefit of this fact, it is also possible to accurately shoot hardened lead balls (wheelweights or linotype bullets shoot very well) from the Forsyth bore. However, I won’t get into the details here. Just read the book.

I know, I know - all these "facts" defy all that many of you have ever thought to be true about muzzleloading rifles. I’m telling you that you just can’t believe the many advantages of the Forsyth system until you’ve experienced it. As I like to say, Forsyth had it all figured out 150 years ago and had overcome all of our modern complaints about muzzleloading rifles.

If you haven’t yet read Forsyth’s wonderful book, The Sporting Rifle and its Projectiles, I will gladly forward the pdf e-book to you if you send a request to me at: underhammers@safe-mail.net. Then you will understand what all the excitement is about.

While there may be other barrel makers who will make a “Forsyth” barrel for you, those listed below are those who responded to my inquiries and who I know have the understanding of the concept and the skill to produce a high quality barrel at a fair price that will provide you with all the benefits that have made us Forsyth shooters as giddy as schoolgirls at a Friday night sleepover.

If you’re a barrel maker and not on the list but would like to be included, drop me a line and we can talk.

Understand that really good barrel makers are very busy which usually translates into some waiting time. So don’t be surprised if you’re quoted 6 weeks to even 6 months before you receive your prize. But truly, it will be worth the wait.


Please contact the following barrel makers for their current prices, terms, and conditions and, of course, tell them that you read of them on The Underhammer Society blog:

Scott Keller or Scott Kelley, Colerain Barrels: www.colerainbarrel.com or phone: 814-632-7513 or e-mail : scott@colerainbarrel.com
Charles Burton, Flintlock Construction, Inc., phone:  606-780-7709; e-mail: flintlockcalb50@hotmail.com

The makers listed above offer barrels up to and including .62 calbre. Those listed below will make barrels of even larger bore as well as the usual small bore calibres.

John Taylor, John Taylor Machine, www.johntaylormachine.com phone: 253-445-4073;
e-mail: john@johntaylormachine.com

Jim Carpenter Barrels, phone: 208-245-3693

Ed Rayl, phone: 304-364-8269

BTW, there is no such thing as an underhammer barrel maker. Most any muzzleloading barrel can be used to make an underhammer so there is no distinction that I'm aware of. However, according to my wife, I could be wrong. So if you know different, please enlighten me.

On my drawing board...

If you’re curious about that custom John Taylor barrel mentioned above, it is being used in the project now on my drawing board. My new dream is a "Nouveau Jaeger" based upon my Faeton design, which will be a 12-bore stalking rifle with overt Germanic influence that will feature that extremely swamped barrel for light weight and perfect balance in the finished rifle. The hammer is one of the more unique features of this rifle and is a stylized acanthus leaf (at least for now).

Clicking on the photo will enlarge it for viewing the detail of this unique, one-of-a-kind underhammer rifle.

The trigger guard is also the mainspring and fabrication of it as one solid piece of spring steel was one of the greater challenges in this design. The grip rail may be of horn or perhaps, ebony, while the loading rod will be metal-tipped, streaked Macassar ebony. The forearm tip subtly suggests a traditional Schnabel without an obvious elephant lip or undercut knob. The wood I have chosen for this project is a nice piece of French walnut - conservative and not too flashy. The checkering pattern, too, will be conservative, although undecided in actual design at this time. Sling rings may be utilized – not sure.

Engraving/etching of the steel receiver and buttplate will be performed in a floral, Germanic Victorian pattern that is graceful and elegant, unlike the later and rather cliché chiseled oak leaf and acorn motif that many associate with Germanic arms. The barrel will wear my exclusive Damascus pattern.

Over all, the finish will be highlighted French gray on the receiver with a light browning of the barrel and buttplate. Screws, the trigger, and triggerguard will be Nitre-blued to a deep cobalt-blue color.

I believe it will be a most unusual, if not beautiful underhammer rifle.

For more information about Faeton rifles, please visit: www.rjrenner.blogspot.com.


Tune in next month for the Underhammer Action Roundup in which we’ll take a comparative look at some of the more readily available underhammer actions. You rifle builders will find it to be most timely and informative.

If any of you readers are making and marketing underhammer actions - or if you know someone who is - and would like to be featured in this upcoming roundup, please contact me right away so I can be sure to include you. Just drop me a line at: underhammers@safe-mail.net and we can brainstorm your feature.



Anonymous said...

Mr. Renner,

I have been following your work for some time and own two Pacific Rifle Zephyrs. Both perform wonderfully and I am very pleased with them in every way.

Now I see that you are offering a Faeton rifle which also interests me. However, the Jaeger rifle on your drawing board really has my full attention. It has the classic European features that I appreciate which are so difficult to find in modern arms.

It is interesting that you are recreating the beauty and grace of the finer European hunting arms, while the Europeans are copying American underhammer patterns.

If you are planning to offer this New Jaeger pattern of rifle to your clientele, please put me on the list as I definitely want one.

Thank you for your effort in providing this informative, and certainly entertaining, blog for the rest of us.

Warmest regards,

William Crane
Houston, TX

Anonymous said...

Dear Mr. Renner,

When I read that you are planning to do a review of underhammer actions, I felt that I must write to you about my experience with one of the underhammer actions. Perhaps some other poor fool may not make the mistake that I did.

First of all let me tell you that I am a mechanical engineer and I really appreciate the simplicity of the underhammer rifle when compared to the traditional sidelock rifles.

A few years ago I decided to build a small game underhammer rifle in .36 caliber for shooting the many squirrels in my back lot. I bought an action from a website on the internet. Very little information was provided, but I figured it was an underhammer and how complicated could it be.

When I received the action I was appalled to see that it used three Allen set screws to hold the barrel and action together. I really could not believe that anyone with any mechanical understanding would use such a method to hold the barrel. Only an amateur would think that was a good idea. I thought to myself that this action must have been one that was returned from a customer who had drilled and tapped those huge holes.

When I finally got a call back from the dealer, he told me that they are all made that way so you can interchange the barrels. That seems like a flimsy excuse for very poor design. There are much better ways to do that than by using three ugly Allen set screws.

The more I thought about it my disappointment turned to anger and I called back to ask for a refund of my money. The dealer never would return my calls and to this day that action is still lying in a drawer in my workbench. I have had some ideas on how to save this action and would like your opinion as I am not a gunsmith.

I would like to tig weld and then dress those ugly holes. Then I will turn a new breechplug to tightly fit the hole in the front of the action because the breechplug that was supplied is sloppy in the hole. Then I will silver solder the breechplug into the action so that they are one unit, like the integral breechplug that was used on the old Mowrey actions. Then I’ll just screw the barrel onto the action. Do you think that will work?

If you review any of those actions that use Allen screws to secure the barrel, I hope that you will not endorse them because it is not a good idea. I remember that Hopkins and Allen used a tapered pin and that’s what I thought I was getting with that action. I guess that no one seems to know how to install tapered pins anymore.

Sorry to carry on, but I hope that my story will save someone else the disappointment that I have in both the action and the dealer who sold it to me.

Scott Petersen, Atlanta, GA

R.J. Renner said...

Hi Scott,

Thanks for your input. I think that Allen screw system is pretty cheesy, too. Using a tapered pin has always been the favored method of the old-time gunmakers who made take-down or swap-barrel rifles.

It amazes me that they try to design an aesthetically-pleasing old school rifle and then shoot themselves in the foot by blatantly using Allen screws.

Close, guys, but no cigar.

As for your fix, yes, your method will work as I've done it a time or two (for special customers) although I don't normally repair other people's mistakes.

Again, thanks for sharing.


Anonymous said...

i want to say that I agree with Scott's comment. thanks for telling us how to fix those actions with the allan screws. i bought a .69 cal. underhammer rifle at a gun show that has those screws that hold in the barrel. the problem is that the gun shoots loose and loses accuracy. it also has a small plastic butt plate and it kicks so much that the stock shoots loose, too. i will try to fix it the way you suggested. now I know why you get so much money for your rifles but i still don't have enough money to buy one. do you ever get any used ones back that you could sell cheaper? email me if you ever do.


Anonymous said...

I don't know what all the fuss is about. The screws don't bother me. The gun works and that' all I'm concerned about.

Bill S.

Anonymous said...


I'm not an engineer, just a shooter who likes underhammer guns. But it seems pretty logical that those allen screws are not mechanically a good idea, especially when there is unequal force applied to them.

Besides that, they look really bad when your trying to make a rifle that looks like a period gun. I mean if your going to use allen screws why bother to make the rest of the gun look like something old?

I also have one of those actions that I got from Deer Creek and I just hate the screws. I had a rifle built for me using that action. Everything on it looks like an early rifle except for those screws. Now I am going to have a gunsmith fix it the way that Scott Petersen suggested and then it will look right.

You mentioned a tapered pin to hold the barrel onto the action and I would like to know how to do that. I've seen it on guns in the Ned Roberts book on caplock rifles and it looks really simple and sturdy. I think I will have my gunsmith look into that too.

Thank you for a great website. I haven't found any other like it and I really like the good pictures that you have.

best wishes,


joelaw99 said...

I just bought one of the actions from deer creek. I too thought it looked terrible.

My plan is to order special drill bit,tapered reamer and tapered pin from brownells (its the double barrel tapered pin repair kit).

I,m going to turn a tight plug of brass to place on receiver and(weld wont stick to it) just mig all three allen holes.
That way no grinding inside frame.
use taper pin kit to attach barrel...

joelaw99 said...

Brownells (brownells.com)sells a kit to fix loose bouble barrel shotgun hinge pins. drill bit,tapered reamer,tapered pin.
I just bought an action kit from deer creek and im planning to mig up the allen holes (will turn a plug of brass to put in frame hole while welding so weld doesnt obstruct hole in frame.)
tighten breech plug in barrel index top flat and drill thru hole thru frame and breech plug to be reamed. If needed you can use thin spring steel shim stock washers (.001-.005 thickness) between back of barrel and front of frame to tighten up barrel if it loosens...

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About Me

Roger Renner

Hi. I've been a student, admirer, and designer/builder of underhammer guns for over 30 years. In that span I've built over 200 semi-custom underhammers exploring the possibilities from the ordinary to the exotic. In 1996 I founded Pacific Rifle Company to explore the market's interest in a high-quality underhammer rifle. Thankfully, that interest was, and still is, there. I sold PRC in 2006 but continue to craft high-end underhammers as I am truly afflicted with underhammeritis - which can be contagious!