Drawn filing on a Military barrel?

[brstevns]

Has anyone drawn file the steps on a military barrel to Oct.? Any Pointers?

[Der Gebirgsjager]

I'm just a little slow in following your drift here. Are you attempting to draw file the entire barrel from round to octagon, or just the steps to octagon; or does Oct. mean October, which is about how long you'll be at it!

I have draw filed a number of military barrels with the steps, but just to get rid of pits, dings, machine marks, etc., preparatory to re-bluing, and the end result was round, but still with the steps. There is a reason for this, although I have to confess I never tried to make one octagon. This may or may not be true in any/all/or most cases, but I read it more than once, was told it more than once, and didn't want to take a chance. The story was that the stepped barrels were made that way on purpose, and that if you remove enough of the barrel metal to make the smooth and tapered by eliminating the steps, you will ruin the barrel's harmonics, and the accuracy. So-- for what it's worth (maybe not much!).

[brstevns]

Just the steps to octagon. Might take to Oct. but with this Virus thing and being in shut down or lock down or whatever you wish to call it, time does not seem so important.

[Winger Ed.]

I'd think the barrel on an infantry rifle is too thin - steps included, to have that much metal removed
and retain anything close to its original harmonics.

It sounds like a cool project, but I wouldn't do it unless I had a much heavier after market barrel to start with.

[gnoahhh]

You better be darn handy with a file!! Any wonkiness generated by such an act would very likely have a detrimental effect on accuracy, not to mention aesthetics.

A buddy of mine who has been a tool and die maker since 1970 recently did just that, but with his Bridgeport milling machine. The victims were a couple M96 Swedish Mauser barrels, cut to 22" and the first "long straight" immediately forward of the knoxform (chamber area) ahead of of the receiver milled into an octagon with the corners left as wide as the original contour. (In other words, just the bare amount of steel removed to create an octagon.) The rest of the barrels' lengths were left untouched other than being polished for bluing. The fly in the ointment: we debated whether there was enough steel left there for a decent margin of safety, so the trick wasn't repeated. Accuracy was so-so, but we didn't have a control base to compare post- versus pre-operation accuracy so that may well be a moot point. One positive note: the barrels were definitely lighter and the finished sporters were noticeably well balanced.

[brstevns]

OK was just a thought. Have a old 8x57 SR barrel that I was going to use. Guess best to just forget the idea.

[country gent]

It can be done and with the right files will go faster than you think. A 12"-14" long cut file will peel it right down, The big thing will be indexing it accurately for the octagon. A simple stand that holds the barrel between centers and support the file level will help a lot.

I did several shafts for canes in tapered octagon ( walnut). the fixture and guides clamped aligned and held the shaft making a very nice shaft with the block plane.

The right files in good shape will cut fast and clean, you also want heavier files that wont spring and cut a slight radius.

[gnoahhh]

Having built a few split cane fly rods, I'm here to tell you that Country Gent's advice is sound. A form with which to guide the hand tool is paramount. Freehand/eyeballing just doesn't cut it for stuff like this where precision is called for. Unless you've lived with a file in your hands for the last 40 years, and even then...

[JSnover]

I'd do it. Unless there's something unique about that barrel and it would be some form of sacrilege, I'd be making up the fixture right now.

[brstevns]

Now you have me thinking. If some believe that filing a 8 sided barrel where the steps are located would make the barrel to thin in these areas why not make it a 12 or even 16 sided? I beleive the effect would look nice and would keep down removing to much metal.

[waksupi]

There isn't enough steel on a 8mm military barrel to do it safely.

[Texas by God]

File facets around the steps only for a unique look. Like a diamond...
Just pitching ideas!

Sent from my SAMSUNG-SM-G930A using Tapatalk

[LAGS]

I did use the breech end of an 8mm Mauser barrel to make a Black Powder pistol.
I cut the chamber section off then
I did file the fattest step to octagon and left the lower step round.
I bored the barrel out to .357 smooth bore and made a breech plug for the end of the barrel.
The filing on the fattest step took forever.

[brstevns]

Maybe just jewel it?

[brstevns]

There isn't enough steel on a 8mm military barrel to do it safely.
You do understand I did not intend to bring the first step down to sane hight as the second. Each step would be filed.

[405grain]

I don't think it's a good idea. It may or may not effect the strength of the barrel, but there's another issue: it won't look right. Skinny as a pencil and octagon barrels just don't go together. A better idea might be to sleeve the barrel. Bore out a piece of octagonal barrel stock so that you can insert the round Mauser barrel inside it like a barrel liner. There wont be any degradation of the strength of the barrel because it will still be the same diameter, without any added stress concentrations. The octagon sleeve can be really thin at the breech end of the barrel because it isn't seeing any load. I've seen this process done on Mauser receivers before to make the receiver rings into an octagon shape.

[JSnover]

Minimal filing might be just fine from a strength/safey standpoint, if all you're doing is cleaning up the steps. Hatcher turned a Springfield barrel to a wall thichkness of 1/16" starting at a point over the shoulder of the chamber, fired three service cartridges without ill effect. Blew it up with a 75,000 psi "blue pill." I wouldn't go that far and I'm sure he considered the barrel unserviceable even before firing the first round but his purpose was different.

[samari46]

The only draw filing I've ever done was having the barrel clamped in a beaver machine used to thread pipe.Mill Bastard file to remove the rough machining marking from the barrel. Had copper sheeting wrapped around the barrel to prevent the chuck jaws from marking up the barrel.Frank

[El Bibliotecario]

While I believe this sort of thing was done in the days of $17 DCM Springfields, today it sounds like a golden opportunity to ruin a perfectly good rifle. But that's just me.

[brstevns]

Seems as if I opened a can of worms

[FrankG]

I have one here somewhere , came off one of the 'cigarette' rifles from WWII .

[brstevns]

I have one here somewhere , came off one of the 'cigarette' rifles from WWII .

Went over my head. Have one what?
Do you mean a barrel?

[Hdskip]

If nothing else take this opportunity as a learning experience . You may be surprised how much you may learn about filing metal. Even if you learn you may not want to do it any more. Question I might have is what would you intend to do with it when finished? I have done a few things in my life that may not have turned out. But I always learned something. Yes I have pitch a few projects in the scrap bin....��

[LAGS]

I have to agree with Hdskip.
Try what you want to do , preferably on some old junk you don't care about.
You can Test your skills and improve them if you need to.
I can't remember any of my projects ending up in the Scrap Barrel.
But that does not mean they turned out like I wanted them to.
(Or what they started out in my mind to be)
But those will be the junk I use when I get another brainstorm.

[brstevns]

If nothing else take this opportunity as a learning experience . You may be surprised how much you may learn about filing metal. Even if you learn you may not want to do it any more. Question I might have is what would you intend to do with it when finished? I have done a few things in my life that may not have turned out. But I always learned something. Yes I have pitch a few projects in the scrap bin....��

I was going to use it on a SR Mauser, just for cast bullet use.

[country gent]

A old tool makers trick when finish filing is to fill the file with chalk, chalk board chalk works well. It dries the file and also reduces pinning. Chalk a new file let set a little while and brush out this removes any oil from it. rechalk and use it.

A good clean dry "sharp" file will run chips out quick and they are sharp and nasty when they stick you. They shear angle when draw filing can really cut quick. Remember a file like a saw only cuts in one direction dragging on the back stroke will dull it much faster.