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From: bartb@hpfcla.fc.hp.com (Bart Bobbit)
Newsgroups: rec.guns
Subject: Re: How much expense to rebarrel a rifle?
Date: 9 Dec 1994 12:30:01 -0500
William S. Rowell (wsrowell@bga.com) wrote:
Winchester can replace the barrel with a factory one for about $120.
A custom barrel will cost anywhere from that to about $400, depending
on the quality you get and who does the work.
Rebarreling requires you have a barrel vise and an action wrench
to hold the receiver and barrel to unscrew and rescrew the barrel.
A 24-inch long Crecent wrench will work on the receiver, but the
barrel vise is usually the tool most folks won't have.
The critical part is getting headspace correct within a few
thousandths of an inch of what's needed. Without the proper tools
to both do and measure this, it's about impossible to do it right.
BB
From: hays@SSD.intel.com (Kirk Hays)
Subject: Re: M1 Garand mail list?
Organization: Intel Supercomputer Systems Division
In article <21d4nuINNdsd@clem.handheld.com>, jmd@cube.handheld.com (Jim
De Arras) writes:
|> Is there a mailing list devoted to Garands? I've started collecting
|> and working on them (put my first new barrels on this past week!!!) and
|> am looking for tips. Such as how in h*ll do you hold a Fulton Armory
|> match grade barrel (completely round barrel) for tightening a receiver
|> on it?
|>
|> I did it, but slightly mared the finish with the vice. :-(
Arg!
A method I've used for more years than I care to think about:
1. Get two small cardboard boxes, the width of your vise jaws,
that'll provide at least 1/2" clearance inside the box around the
barrel after you cut a half-circle in the ends to lay the barrel
in. The final casting should be at least 1/2" thick at it's
thinest point, in other words.
2. Apply a "release agent" to the barrel. Depending on the epoxy
your using, this might be a spray, paste wax, etc. Make it as thin
as possible, but be sure to have a complete coat. Fill any holes
with clay or sealing wax before applying the release agent.
3. Mix your epoxy (I prefer Brownells Acra-glass, it is the
strongest and most predictable), and fill the first cardboard box.
Place a straight, parallel portion of the rifle barrel into the
epoxy, as close to the action as possible (this reduces the lever
arm when you are torquing on the action). No more than half the
barrel diameter should be in the epoxy.
4. Let the epoxy set.
5. Remove the barrel from the casting you've made, clean off any
flash, and remove the release agent from the barrel and the casting.
6. Replace the barrel in the casting, and treat exposed surfaces
with release agent. I suggest using a rubber band made from an
innertube to hold the barrel in the casting - lay the barrel on the
band, place the casting on top of the barrel, and then pull the
sides of the band over the back of the casting. I often put a piece
of release-agent treated cardboard on the inner faces of the first
casting, to provide a spacer between the two halves of the casting.
Tape also works for this purpose.
7. Mix epoxy, and fill second box. Place the barrel and casting
on top of the second box, with the barrel in the second batch of
epoxy. Let it set up.
8. Repeat clean-up step, removing all flash and release agent.
Remove the cardboard spacer (if any). Removing the outer cardboard
is not usually necessary, and I leave it on, with a note as to
which barrel it fits.
You now have a perfect casting of your barrel, in two pieces.
Treat it with rosin (available from any music supply store), clamp
it in your vise around your barrel.
You can also make jaws for your action wrench this way.
If, at any point, you find you've epoxied your barrel to something
it shouldn't be epoxied to, heat from a propane torch will allow
the epoxy to be removed.
|> Out of sight after assembly, at least!
Trust me, it'll bother you as long as you own the gun.
--
Kirk Hays - NRA Life, seventh generation.
"The only thing necessary for the triumph of evil is for good men to
do nothing." -- Edmund Burke (1729-1797)
[I do not speak for Intel, not being an officer of the corporation.]
From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Newsgroups: rec.guns
Subject: Re: Barrel Fitting -- A FAQ Question?
Date: 17 Apr 1994 18:12:27 -0400
Fitting a barrel to a centerfire rifle starts with getting a rifled
blank. That blank may or may not be profiled and cut to the length
one desires. If not, it can be turned down on a lathe to the profile
one needs. The best way is to put a live center in both ends so the
outside will be turned concentric with the bore. Turning the barrel's
diameter to a smaller one will do the following to its bore and
groove diameters; if the rifled blank is:
* button rifled, they'll get bigger.
* cut or broach rifled, they'll probably not change.
* hammer forged, they'll get smaller.
And when they change, they do so irregularly; 'tain't the same change
throughout the barrel's length. Although they may change only a few
ten-thousandths of an inch, that's enough to degrade whatever accuracy
level they had to start with.
Crowing the barrel's front end may be next. Holding the barrel's
breech end in the lathe's headstock, its muzzle end is held in a
steady rest. Best crowning is attained when the barrel turns on
its bore axis. Precision live centers are oft times used in the
muzzle so that part turns well centered on the lathe's tailstock
to turn down the muzzle's outside diameter. Once that's done, that
part is put in the steady rest and the bore then turns on its center.
The muzzle is faced at some angle to the bore with the cutting tool
starting inside the bore and moved out with the lathe's crossfeed.
11 degree facing tends to produce the best accuracy, but as long as
it's straight, that's fine. Some folks put a rounded muzzle face
on the barrel so they look like factory barrels. After facing the
muzzle, the crown on the rifling is done. A brass ball about twice
the bore diameter has lapping compound on it and it's pressed into
the bore just enough to deburr the rifling and make it smooth and
uniform. Some folks use different tools, but they all do the job.
Once the barrel is profiled, shanking it is usually the next step.
The muzzle end can be held by a lathe's headstock, but the breech end
is usually held in a three-point steady rest a few inches in front of
where the barrel tenon, or shank will be cut and threaded. If the
barrel's back end diameter is concentric with the bore axis, then the
bore will spin well centered. If not, then a live center should be
put in the bore's breech end and the outside diameter turned to get
it trued up, then put that part in the steady rest.
The diameter, thread count, and length of the barrel shank needs to
be determined. That part is then turned down and threaded. If an
extractor cut needs to be made on one side of the barrel's breech
face, that can be marked by putting the barrel in the receiver, then
marking where the extractor will go. Extractor cuts are made on a
milling machine or a milling attachment put on the lathe's crossfeed.
Chambering is the next thing. Again, the breech end's in a steady rest.
Some folks with bigger lathes have the muzzle end sticking out of the
back of the headstock and held there by a three or four jaw chuck; the
chamber end is held by the front chuck. Regardless of the setup, it
is important that the barrel blank turn well centered on its bore at
the chamber end.
A roughing reamer is used to remove most of the chamber parts metal.
The actual chambering reamer is then used to ream out the chamber to
fit the cartridge. As the distance from the closed bolt's face to
the headspacing part of the chamber is critical, a good machinist
will determine how far the chambering reamer needs to be put in the
bore.
Chambering reamers are made in two types; solid or floating pilot. A
pilot is what centers the reamer on the bore's center.
Solid pilot reamers have a round part at the chambering reamers front
end. That pilot is a few thousandths of an inch smaller than bore
diameter. Floating pilots are screwed into the reamer's front end; they
come in different diameters. If the pilot's diameter is only a few
ten-thousandths of an inch smaller than bore diameter, the chamber's
throat will be very well centered in the bore; very important for
best accuracy. Floating pilots turn with the barrel and don't marr
the bore in front of the throat and leade. Solid pilots sometimes do
marr the bore and oft times don't center the throat and leade very well.
After the barrel is shanked and chambered, it's screwed into the
receiver and torqued up. One doesn't need a lot of torque on the
barrel. A 2-foot long action wrench is enough; some folks use shorter
ones. Headspace is checked and if it's too short, the barrel can be
removed and the chamber reamed a tad deeper. Sometimes, the chamber
reamer can be put through the receiver on an extension, then the
chamber deepened the correct amount.
I didn't mention standard machine shop practices regarding how fast
the barrel turns, lubricating the reamers, how fast to push them into
the bore and finally keeping the chamber clean and the chips removed
frequently. That's something one needs to do correctly.
The order these things are done isn't fixed. You can chamber the barrel
before shanking it. You can turn down its outside diameter after it's
shanked and chambered.
BB
From: bartb@hpfcla.fc.hp.com (Bart Bobbitt)
Newsgroups: rec.guns
Subject: Re: Barrel Fitting -- A FAQ Question?
Date: 18 Apr 1994 21:02:35 -0400
The Rifleman (sybok@athena.mit.edu) wrote:
: Sounds like you have a lot of experience in gunsmithing.
Not really.
: However, I was asking about how you would
: attach a factory-complete barrel that
: you, say, obtained from Quality Parts
: to a finished receiver.
You'll need a barrel vise and an action wrench. These must be fitted
to these respective parts so when torque is applied, they'll tighten
up correctly. A helpful local gunsmith can help you get them and show
you how to use them, too.
Once you have the tools, first remove the old barrel. Then screw in
the new on by hand as far as it will go. Then put the barrel in the
barrel vise and tighten it up. Put the action wrench on the receiver
that's had its bolt removed, then tighten the barrel in the receiver.
If the barrel has been profiled for a certain type of rifle, you'll
need to align it correctly with the receiver. This isn't hard to do
if one understands what has to align with what. Sometimes, the barrel
won't tighten up enough to `clock' into alignment, even when you and
25 of your pals are hanging on the action wrench's handle. If this
happens, you gotta turn back the barrel tenon's shoulder where it
contacts the receiver; a lathe is the best thing to do this with.
After the barrel is properly fitted to the receiver, use a `go' headspace
gage in the chamber and close the bolt; the bolt should close easily.
Then use a `no-go' headspace gage and repeat this; the bolt should not
close. If both these things happen as indicated, you're finished. If
the bolt will not close on the `go' gage, or it does close on the `no-go'
gage, finding a bolt that will fit correctly is the easiest thing to do.
If spare bolts aren't available, then you have to:
* Use a chambering reamer to deepen the chamber if the bolt won't
close on the `go' headspace gage.
* Set the barrel back one thread by reshanking, rechambering, then
trying again. But this doesn't work with barrels profiled for a
specific receiver and has a gas port in it. You may need a new
barrel.
BB
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