"Rounded" Grooves or Lands at Muzzle?

[Smollett]

I'm new here.  Please forgive me if this has been addressed elsewhere, but I can't seem to find an answer in reviewing crowning or coning topics.   There is a look I have noticed on original rifle muzzles that appears simpler than a fancy "Hiney" muzzle, but is nonetheless attractive.  I'd like to know if it's some sort of coning or simply decoration.  Also, are the rounded profiles at the muzzle lands or grooves?  I'd love to have this done and would appreciate any guidance.  Here's a photo: [url[/url]

Thanks very much, Smollett

[Ky-Flinter]

Hi Smollett,

Welcome to ALR.  Looks like decoration to me, filed into each rifling groove with a small round file.  Coning involves removing more material all the way around the muzzle opening, resulting in sort of a funnel shape that makes loading a patched ball easier to start.  The lands are the "raised" surfaces between each groove.

-Ron

[WadePatton]

If this isn't done very carefully, there could be an uneven result which could allow gasses to escape at one (or more) groove(s) before the other grooves. That might prove detrimental to best accuracy. 

I'd not attack it myself until i understood more about muzzles and crowns and cones and sech. 



Easy enough to fix though.  Saw off 1/4" and start over. 

[smylee grouch]

There are those who do that treatment to the lands at the muzzle so loading a tight combination wont damage the patch. Kinda like swaging the patch-ball combo into the barrel.

[Dennis Glazener]

For what its worth I did one like this, used a small chain saw file then finishdd it with wet or dry paper wrapped around a small piece of drill rod. Counted each stroke to insure same amount came off each groove.
Dennis

[rhbrink]

This looks like nothing more than a decoration to me. If there is some patch cutting going on it would be on the leading edge of the top and corner of the lands where that edge would intersect with the taper of the crown not at the bottom of the grooves.

My $.02 worth on this issue.

RB

[J Henry]

 Dennis    when you count strokes to ensure the same amount is taken off ,,,  how do you account for the difference in pressure  I was just wondering if you applied more pressure on a stroke than another wouldn't that result in more metal being removed??  Want to get the procedure correct before I ruin a barrel ,,also could I do a barrel with a Carborundum stone or Diamond cone  , like I use for sharpening my square drill chisels,it is cone shaped and shapens the inside cutting surface of the part held by the quill..

[bob in the woods]

I did my barrel in a similar fashion, only I filed the round bottom grooves in the lands. This allows much more room for the patch to seat and my tests proved to my satisfaction that it did not affect the accuracy.

[Smollett]

So does this mean that the lands are lower than the grooves at the muzzle?  If so, that sounds like it might ease loading similar to coning.  It's really hard for me  to tell from photos.   Simply cutting the rifling deeper without doing anything to the lands seems like you'd have cut patches all the time without any easier time loading. 

What looks so simple is truly complicated for me (nothing new...)

Smollett 

[bob in the woods]

Yes, the grooves filed into the lands extend out to the muzzle. It does ease loading.

[L Moler]

That particular rifle appears to be flat bottom rifling made to appear round bottom at the muzzle..  Therefore, I would say that it is purely decorative.
I have done a couple like that, and have done most of the Jaegers I have made like the one in the photo.
I crown the muzzle first, then I cut the decorations, making sure that my cuts do not go any deeper than the bottom of the crown.. 
As of yet, I have not had it affect the accuracy in any way.

[D. Taylor Sapergia]

Here's an interesting photo of the muzzle of my Uberti 'Deringer' pistol.  It clearly shows that it is the grooves or furrows that have been filed, while the edge of the lands has been just gently rounded.  I tried several approaches to this treatment before I committed to having at the muzzle of my Virginia rifle:  on scrap barrel stubs I filed grooves on one and lands on another.  I studied too, the images in 'Steinschloss Jaegerbuschsen' where many if not most of the muzzles on those perfectly preserved 'stutzen' rifles have been filed.  Satisfied I was headed in the right direction, I filed out the GROOVES of the Rice barrel on my rifle, after having cut a very gentle crown to relieve the lands.  I too was concerned that I might diminish the accuracy of this otherwise excellent rifle, but it did not.
To achieve uniformity, and I feel that that is critical, I placed a brass rod into the bore over which I slipped a close fitting washer.  I cut a notch in the washer so that I could insert a scribe in the notch, and used it to mark a ring on the muzzle's face which indicated the extent of where the grooves would end.  I used a small chain saw file, having capped the end with a small rubber glue bottle stopper, to protect the bore from accidental contact in the bore.  and I cut each groove by eye as uniformly as I could.  Like Dennis, I polished the file work to 400 grit, and called it done.
And it does load easier than a simple crowned barrel.  There is more room for the patch to fold and allows the lands to more easily 'engrave' the soft lead ball through the patch, without tearing or cutting it.  Cutting the decoration in the LANDS would amplify this virtuous property, as BITW has explained.
It appears to me that upon studying images of Hawken rifles in Jim Gordon's 3rd Volume, that this was also a common crowning technique in the Hawken shop.

[EC121]

I have a .30cal. rifle that I used an oval  needle file on.  It was loading hard.  I just barely broke the sharp edge of the lands and rounded the bottom of the grooves a bit.  All by eye.  It loaded easier and accuracy wasn't affected.  It really wasn't much more than polishing(and not decorative) but it helped loading.  I did the same to my .40cal. with the same result.

[smylee grouch]

On several ocations as I was goin g through Jim Gordons museum I noticed that many gunmakers finnished the crowns by groving the lands at the crown.  I have seen it on original Leman's and at least one Henry rifle plus Hawken.

[Smollett]

Here's another example (the left-side barrel).  This type I have seen quite often on original rifles.  It almost looks as if the rifling was simply cut all the way through the end, but from the discussion that's most likely not the case.  So what was done and why?

[Dennis Glazener]

Dennis    when you count strokes to ensure the same amount is taken off ,,,  how do you account for the difference in pressure Huh  I was just wondering if you applied more pressure on a stroke than another wouldn't that result in more metal being removed?

I suspect there would be some slight difference. I am just used to counting strokes when doing repetitive filing. My dad taught me to do that when sharpening a saw blade to keep it cutting straight.

Thinking about this I will pose a question for which I have no answer but I bet we will get a few. Let's say you did, by hand, the procedure mentioned in this topic. And lets suppose there is some minor difference but there is no sharp burr or other place left to cut the patch. Would this cause a barrel to be in-accurate? Not talking about a small change of impact I am talking about impact changing from shot to shot. I say no since the slight difference will be consistent from shot to shot. Comments?
Dennis
 

[EC121]

I calculated the time a ball spends at the muzzle.  It is in the 4th decimal place assuming a .1" length of crown.  Something like .0007sec. or less.   To my way of thinking it would take a really bad filing job to have an effect on the flight of the ball.  In addition part of the effect would be cancelled by the opposite side of the muzzle so only the difference between the two sides would act on the ball.  Any thoughts?

[WadePatton]

I calculated the time a ball spends at the muzzle.  It is in the 4th decimal place assuming a .1" length of crown.  Something like .0007sec. or less.   To my way of thinking it would take a really bad filing job to have an effect on the flight of the ball.  In addition part of the effect would be cancelled by the opposite side of the muzzle so only the difference between the two sides would act on the ball.  Any thoughts?

Yeah (i repeat myself but), crown concentricity is paramount to ultimate accuracy-that's what false muzzles are all about.  I'm not an established BP target shooter, but spent some years collecting trophies with those other jobbies.  .0007 seconds (or less) it plenty of time when it comes to the transition between internal ballistics and external ballistics.

[smylee grouch]

Interesting observation Dennis. We can theorize all day about what the results would be but an actual shooting test would probably be more convincing. What we need then is a rifle that has a somewhat uneven treatment and we could test shoot the thing to see if it did still group to our satisfaction.

[Ted Kramer]

Smooth bore barrels can be "regulated" by taking a few thousandth's of an inch off one side and they will shoot consistently (as consistently as expected for a smooth bore). I have also seen rifles with muzzles so out of square with the bore that it could be noticed from across the room and they shot very well. IMHO,accuracy loss from a barrel with one groove fancied up a wee bit differently at the muzzle than the others probably wouldn't be noticeable unless the rifle was held perfectly still when fired-an accomplishment I have not yet mastered.
TK

[Acer Saccharum]

I find that the rounded gullets filed at the muzzle DO HAVE A FUNCTION, not just decorative.

When using pre-cut patches, and when the ball is pushed into the muzzle, the extra patch material naturally goes into the gullets in a very even and organized manner. These puckers are more regular and evenly spaced than if the muzzle gullets were not filed. With grooves filed, each one of the grooves gets an even distribution of extra material.

[Smollett]

Acer, did you gullet the lands, or the grooves?

Smollett

[shortbarrel]

I talked to the late Don Getz at Conner Prarie while he had a barrel between his legs filing the muzzle with a needle file. He said he was just decorating the muzzle. I think it was one of his barrels.   

[kaintuck]

Y'all....take a look at Charles Burton barrel ends......it works.

Marc n tomtom

[Smollett]

Well, I stumbled across (wasn't looking for it even...go figure) an older post by Herb, who, IMHO, hit the nail on the head (Hallelujah!).  Here is his answer (note it is indeed the LANDS which are filed the deepest to give the look):

"I just talked with Doc Gary White (owned the old Green River Rifle Works) about this treatment of the Jim Bridger Hawken.  He said he has seen hundreds of original rifles of many different schools of building with this muzzle treatment.  The Kit Carson rifle is done this way, too.  Doc said the grooves are deepened by filing a taper back about 3/4" into the bore, then the lands are filed down even deeper at the muzzle to give that kind of gear look.  This accomplishes muzzle coning such that a short starter is not needed.  I am considering doing this to my Bridger Hawken I just built, but will shoot it as is for a while.  To do this, I would make a tapered cone with abrasive paper held on it, perhaps with glue, to cut a 3/4" long cone to just below the grooves at the muzzle.  This would give a concentric end to this cone, important for accuracy.  Then I would file the lands deeper at the muzzle with a needle file to give that "gear" effect."



Smollett