| Author |
Topic: Barrel break ins |
bullseye
Senior Member |
posted September 25, 1999 12:38 AM
I've seen messages posted on this board refering to breaking in of
new barrels. What is this procedure? Is it different for chrome
lined vs. regular barrels?
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Gale McMillan
Senior Member |
posted September 25, 1999 10:10 AM
The break in fad was started by a fellow I helped get started in the
barrel business . He started putting a set of break in instructions
in ever barrel he shipped. One came into the shop to be installed
and I read it and the next time I saw him I asked him What was with
this break in crap?. His answer was Mac, My share of the market is
about 700 barrels a year. I cater to the target crowd and they shoot
a barrel about 3000 rounds before they change it. If each one uses
up 100 rounds of each barrel breaking it in you can figure out how
many more barrels I will get to make each year. If you will stop and
think that the barrel doesn't know whether you are cleaning it every
shot or every 5 shots and if you are removing all foreign material
that has been deposited in it since the last time you cleaned it
what more can you do? When I ship a barrel I send a recommendation
with it that you clean it ever chance you get with a brass brush
pushed through it at least 12 times with a good solvent and followed
by two and only 2 soft patches. This means if you are a bench rest
shooter you clean ever 7 or 8 rounds . If you are a high power
shooter you clean it when you come off the line after 20 rounds. If
you follow the fad of cleaning every shot for X amount and every 2
shots for X amount and so on the only thing you are accomplishing is
shortening the life of the barrel by the amount of rounds you shot
during this process. I always say Monkey see Monkey do, now I will
wait on the flames but before you write them, Please include what
you think is happening inside your barrel during break in that is
worth the expense and time you are spending during break in
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Paul B.
Senior Member |
posted September 25, 1999 04:00 PM
Mac. SUSPICIONS CONFIRMED!
Paul B.
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Gizmo99
Moderator |
posted September 25, 1999 06:53 PM
No flame here Mr. Mac. When my personal history is comparable to
yours, I may throw rocks - not until then though.
I have done this on factory barrels and had good results. I
usually use JB compound for the first few shots and through cleaning
after range sessions. The aggressive use of JB seems to smooth
things up pretty quickly. (duh) I do not have a custom barrel on any
of my rifles. (yet)
Would you still hold that the procedure is unneeded on factory
barrels?
Giz
------------------
"Hear the voices in my head, swear to God
it sounds like
they're snoring." -Harvey Danger, "Flagpole Sitta"
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Gale McMillan
Senior Member |
posted September 25, 1999 07:52 PM
I answered this and lost it on transfer so will shorten this one and
try to get my point across in fewer words. When some one uses JB on
one of my rifles I void the warrantee! For two reasons. ! it
dimensionally alters the barrel dimensions and not evenly and the
second reason is the barrel maker laps the barrel with a grit of
lapping compound that is most effective in preventing metal fouling.
Then a customer polishes that finish away with JB.
I wouldn't be
as apposed to it if it were applied on a lead lap and very
sparingly. It is very obvious when you look at a barrel with a bore
scopes all the sharp edges are worn off the rifling. if it has JB
used on it on a regular basis. As you know ,it is an abrasive of
about 1000 grit. As for using it on factory barrels I will say that
while it is difficult to hurt a production barrel but the thing that
hurts a match barrel will do the same to a factory barrel
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Paul B.
Senior Member |
posted September 26, 1999 04:07 PM
I understand what you are saying about JB compound, but, for
example, I have a rifle in .375x338 Mag that copper fouls so badly
that even JB bore paste doesn't do it. Even the stronger solvents
don't seem to phase the stuff.
I have several other rifles that
are just as bad.
What would you suggest I do? Please don't say
buy another rifle. If I do, my wife will kill me.
Paul B.
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Gale McMillan
Senior Member |
posted September 26, 1999 05:49 PM
Pual I would rather see you use Otters Foul out as it is easy onthe
barrel. I have only used it on my 50 but it worked well on
it.
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Andygold
Senior Member |
posted September 26, 1999 07:12 PM
Gale,
Please excuse my poor memory 8^)
If I remember
correctly, at AR15.com or maybe at Bushmaster's site I read
something about having to fire 100 - 150 rounds with no cleaning or
perhaps minimal cleaning. The article said something about leaving
some residue in the barrel to help polish/smooth the barrel's
internal finish. To clean the barrel before completing this break in
procedure would put you back at square one. This pertained to an
AR15 with a chrome lined barrel.
From what you are saying... I
take it the break-in will only be a waste of ammo. Am I
understanding you correctly?
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Gale McMillan
Senior Member |
posted September 26, 1999 07:35 PM
Thats right. it is a waste of barrel and time. I don't know much
about lined barrels but it may be that the barrel is rough due to
the plating process. With high volume fire as in full auto it helps
to protect against erosion and no one is concerned with accuracy as
it is spray and pray.
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slabsides
Senior Member |
posted September 27, 1999 04:24 PM
bullseye: My credentials aren't as impressive as Mr. McMillan's, but
I do have some experience with new factory barrels and used ones
that have been neglected or abused by previous owners. Factory
barrels aren't lapped or polished as a rule; the first couple of
hundred shots through therefore, apparently serve to 'season' the
bore, wearing away microscopic imperfections. Especially during this
time, firing too many rounds too fast is not a good practice. I try
to keep the barrel cool, especially until a few hundred shots have
gone down the bore. That means that at least at first, I shoot only
a few shots per session, and of course cleaning after each session.
It's not so much the cleaning that helps is the gradual wearing in.
I have used JB Paste for years on neglected barrels, to scour out
years of fouling there was nothing better until the electric
de-re-unplaters came along. Maybe JB isn't good for fine lapped
bores. All I know is that it is a rejuvenator and accuracy restorer
on neglected barrels of the ordinary kind. As for chrome plated
bores I have little experience with them, and can make no
recommendation. slabsides
------------------
An armed man is a citizen; an unarmed man
is a subject; a disarmed man is a slave.
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Gale McMillan
Senior Member |
posted September 27, 1999 06:16 PM
Barrel makers luv ya! If you have a bad barrel there isn't much that
can hurt it or help it for that matter.
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Mal
H
Moderator
|
posted September 27, 1999 06:55 PM
Gale, may I pick your brain on a question I have been wondering
about? It has nothing to do with bbl break in, but this is as good a
place as any to ask it.
You mentioned above that JB, and I'm sure other compounds or
cleaning methods (I think the 'tornado' brushes are a plot by the
factory bbl manufacturers), will wear down the sharp edges of the
rifling. My question is how important is the sharpness of the
rifling to accuracy. Have you done any experiments with sharp vs.
dull rifling, all other aspects of the bbl being equal? Maybe this
type of examination would be a better test of when a bbl has bit the
dust instead of throat wear, for instance.
TIA
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Gale McMillan
Senior Member |
posted September 27, 1999 09:48 PM
Look at it this way, A barrel starts out with nice sharp areas of
the corners of the rifling . Along the way you build a big fire in
it a few thousand times and it burns the corners off. Now take a
barrel that to break in you put an abrasive on a patch and run it in
and out. The result is that you take the corners off the rifling so
that all that fire which would have started with sharp rifling is
now starting with rifling that is thousands of rounds old. Which
means that a lot of the life is gone. A lap always cuts more on each
end where the compound reverses direction as it starts back through
the barrel which means that it is enlarging the bore at each ends of
the barrel. And last picture a patch riding along the barrel with
abrasive on it. It is removing material at a given rate. It comes to
a place where there is copper fouling and it rides over it cutting
the same amount that it was cutting before it came to the copper.
You continue until all the fouling is gone and what have you done?
You have put the came contour in the barrel steel that was in it
when it was metal fouled. It would not be as bad if it were used on
a lead lap but I ask why would you want to abuse the barrel when you
can accomplish the same thing without the bad side effects. There is
Sweats, Otters foul out or just a good daily cleaning with a good
bore cleaner till the fouling is gone. To top this off I will relate
a true happening. I built a bench rest rifle for a customer and as
usual I fired 5 groups of 5 shots and calculated the aggregate. It
was good enough to see that the rifle was capable of winning the
Nationals so I shipped it. I got a call from the new owner saying
how happy he was with it the way it shot. About 4 weeks later the
rifle showed up with a note saying it wouldn't shoot. Sure enough
when I tested it it was shooting groups three times the size if the
ones I had shot before I shipped it. When I bore scoped it the
barrel looked like a mirror and the rifling wasn't square it was
half round. From that time on I put a flyer in each gun saying if
any abrasive was use in it voided the Warrantee.
Now I am not
trying to stop you from doing what you want but just inform you what
is happening when you use JB. Brass brushes are softer than barrel
steel and does no harm. S/S brushes are harder than barrel steel is
definetly a no no. Nylon may surprise you to know is very abrasive
If you doubt this look at the carbide eye on yout fishing rod where
nylon line has worn groves into it.
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Mal
H
Moderator
|
posted September 27, 1999 10:15 PM
If the previous post was for me, I believe you misunderstood my
question. I absolutely believe you are correct about not using
abrasives. My question was on the effects of rounded rifling on
accuracy. Since the rifling is there to impart an angular velocity
to a bullet, I was wondering if you had done any experiments with
sharp vs. rounded rifling to see how much it affected the accuracy
and any theories on why it affected it. My comment on the tornado
(SS) brushes shows that we are of a like mind on this. My theory is
that, as you hinted at, the use of abrasives near the muzzle create
imperfections in the roundness of the bore and greatly affect the
bullet as it leaves the muzzle. Since it is almost impossible for a
human to impart the same cleaning action on the entire inside
diameter of the muzzle evenly, they can ruin the muzzle very
quickly. Any imperfections in this area, no matter how minute, can
affect accuracy. Using any harsh cleaning methods can cause these
imperfections.
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Gizmo99
Moderator |
posted September 27, 1999 10:41 PM
This is very interesting to me. I have used JB and other compounds
and I am rethinking that use. Outers cleaning kits are fairly
inexpensive..............
John Feamster once wrote that his break in procedure for a target
rifle was to clean every 60 rounds or so..
The Barnes folks tell you to clean when your barrel stops
shooting well..
Things to think about. I still like an aggressive cleaning on
factory barrels for the first few rounds. Might have to get the
Foul-Out and see how it works. Time for a new gun !!!!
Giz
------------------
"Hear the voices in my head, swear to God
it sounds like
they're snoring." -Harvey Danger, "Flagpole Sitta"
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artech
Senior Member |
posted September 30, 1999 08:24 AM
As far as the stuff about AR15 barrels on the Bushmaster website
goes, that is for chrome lined barrels only, and it says so in the
text. I know because I'm the guy that wrote it. In our experience at
the factory, barrels would get less fouling if they were fired 200
or so rounds before the first cleaning, then cleaned whenever the
accuracy started to suffer. We recommended this on our lined barrels
only, as the DCM rifles with unlined barrels we tried this on in
testing didn't respond well to it. A "Foul Out" unit is probably the
best bet for those, or any unlined barrel, and is handy for getting
out fouling on lined barrels as well.
Everyone should be aware that this is one area that is being
driven by popular demmand right now, with little or no real research
being done by anyone in the industry. Barrel break-in is rapidly
becoming a popular myth, where some people will tell you straight
out that no rifle will shoot if it's not "broken in" right. Well,
that's just crap. Any barrel made well will shoot well unless it's
neglected or abused, and that's just a simple fact. Any effect
breaking in a barrel may have would probably have to be measured
with a micrometer at the target, as the difference would be almost
neglegible.
I used to put it this way. Unless you are firing from a solid
benchrest, with front and rear rests, handloaded match ammo made
specifically for the barrel you are shooting, and firing single
shots allowing the barrel to cool between each round, you won't be
able to tell the difference anyway, so for crying out loud, go shoot
your rifle! More time using it and less time playing with it, and
you'll be a lot happier. Works on a lot of levels, if you get my
meaning.
That's my $.02, if it's of any use to anyone. Don't go nuts with
breaking in rifle barrels, it's not worth the trouble. As always,
IMHO, YMMV, etc...
------------------
With my shield or on
it...
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Long Path
Moderator |
posted September 30, 1999 09:29 AM
With regard to break-in of factory barrels, I can offer this
observation: In three brand-new rifles that I broke in over the last
3 years, (700, M-77 Mk II, M-70) I ran dry patches through each and
found... shavings! No kidding! I was esp. shocked to find fresh
stainless steel shavings down the bore of the Sendero! You can do
what you want afterwards, but ALWAYS clean the bore thoroughly
before that first shot out of a production rifle. You might also
want to strip the action and carfully wipe the lugs, too. I just
can't believe that steel shavings grinding down your bore with the
force of your first group can be very good for your future accuracy!
------------------
Will you, too, be one who stands in the
gap?
Matt
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Gale McMillan
Senior Member |
posted September 30, 1999 10:20 AM
The metal shavings would have had to get in the barrel after it was
test fired. The barrel was a hammer forged or buttoned barrel which
is not machined and is very smooth finished. No one ever said not to
clean a new rifle only that it is not necessary to break it in.
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