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garandman
July 23, 2007, 07:03
Is it possible to re-crown a barrel muzzle yerself?

Or do you need a lathe?

What tools would I need?

Any tips would be appreciated.

johnny
July 23, 2007, 07:26
the Jeter has used compound and a marble, guess it depends on the barrel, as in surplus or tackdriver, you may not want to go this route with a tackdriver unless it has to be recrowned anyway then you could always try it first.
As always my advise is worth what you paid for it
johnny

Fred-in-PA
July 23, 2007, 08:23
Take a look at item # 168-568 in the Midway catalogue (ECT M1 Garand Muzzle Crown Facing Tool) says it can be used in a lather or with a
T-handle.

garandman
July 23, 2007, 08:33
Fred -

thanx for the Midway cat no.

johnnny -

I'm looking for a 1.5 - 2 moa gun, or a little better. Not a tack driver.

garandman
July 23, 2007, 10:05
Ahhh....I see.

This butt puckering method will get me 2" groups at 100 yards?

ce
July 23, 2007, 15:55
It would appear that your comprehension of the technique is "low".

If your booger finger is erstwhile occupied, you may also use a .45 bullet and 500 grit paper to chamfer the muzzle, especially one that's seated in a round of .45 Colt.

garandman
July 24, 2007, 08:57
Originally posted by ce
It would appear that your comprehension of the technique is "low".

If your booger finger is erstwhile occupied, you may also use a .45 bullet and 500 grit paper to chamfer the muzzle, especially one that's seated in a round of .45 Colt.

My comprehension of this is "low."

Mostly cuz of comments like " especially one that's seated in a round of .45 Colt."

What the heck is a muzzle that's seated in a round of .45 Colt?

ce
July 24, 2007, 09:09
No, no, a bullet, a bullet that's seated in a round of .45 Colt.

That way you have something to hold onto.

I guess you're going to use the store bought tool, so maybe that would be best.
If you change your mind, and decide to try the butt puckering method, use something larger.
Try a potato.

garandman
July 24, 2007, 10:24
Originally posted by ce
No, no, a bullet, a bullet that's seated in a round of .45 Colt.

That way you have something to hold onto.

.

Oh....you mean an unfired ROUND of .45 Colt.

To chamfer a .30 cal AR barrell.

Why didn't you say so?

jgr762
July 29, 2007, 07:51
He did.

Radio
July 29, 2007, 08:29
Now you've done it. You're gonna get called a "douchebag" any time now.

shootist87122
July 29, 2007, 08:41
Brownells also sells barrel facing and crowning tools of various angles. In most cases you will only ruin one, or at most two barrels whilst learning the proper application of same. :rolleyes:

Temp
July 29, 2007, 10:43
Get a round headed brass screw with a head about 5/8" in diameter and some "Clover" brand lapping compound.

Chuck the screw up in a hand drill,.. glob some of the lapping compound on the head of it it,..stick it against the muzzle and let 'er go!

You can put a very pretty crown on a barrel like this.

Mebsuta
July 29, 2007, 11:45
Yup that's the eezy way. I just used a plain steel carriage bolt and lapping compound from Pep Boys. Works fine on junky Mausers and Rushin rifels.

muttman
August 04, 2007, 02:03
I just use a 1/4" brass screw (ball head), compound, and 12.5 volts of portercable's best on slow. the buger picken way will work but then I would have a worn out finger and lots of bugers. muttman

ggiilliiee
August 04, 2007, 12:38
i get (one) inch groups with a flat muzzle .....hmmmm ..gasses if youve ever looked at a slow mo vid of muzzle blast...youll see the gasses dont even spread out to a 10 angle untill is 7 inches out of the muzz .....the crown is about as usefull as a crown on q-victoria head ..
what cracks me up is guys will do allthis ....make re-loads down to the micron ....picatinny portable BBQ holding rails and a embossed pic of carlos hathcock on the stock ....then drop a mag in and have the lack of rail width to stop the 18 lb recoil spring from cleaving the bullet noses off on the ramp along with 80% probability of knocking a bullet back into the case and changing o.a.l on every shot ......go figure

oh the suffering ......

Truckinmike
August 05, 2007, 07:04
I just recently purchased the Gunplumbers video and workbook. ITS WORTH ITS WEIGHT IN GOLD. The DVD has a how to on crowning the barrel.

http://www.arizonaresponsesystems.com/

This guy even shows you how to make some of your own tools! An absolute great buy. The amount of information that he gives out is incredibly generous. Especially when one considers he is in the business of building the very same rifle he is showing you how to build. In fact, I was so impressed, I was thinking about sending him one of my guns to re-build; just because of his generosity with information.

Sorry for the ad nauseam Advirtising ...but thems the facts!

Truckinmike

pryde
August 10, 2007, 00:15
I tried the lapping compound + marble trick and worked on the crown of my R1 for about a half hour then used 500 grit paper and used the booger picking method to clean it up.

Went to the range today and it shrunk the groups from about 5 MOA to 2 MOA. Was really surprised at what a difference it made.

Thank you once again FALfiles.

the gman
August 10, 2007, 19:08
Originally posted by ggiilliiee
i get (one) inch groups with a flat muzzle .....hmmmm ..gasses if youve ever looked at a slow mo vid of muzzle blast...youll see the gasses dont even spread out to a 10 angle untill is 7 inches out of the muzz .....the crown is about as usefull as a crown on q-victoria head ..
what cracks me up is guys will do allthis ....make re-loads down to the micron ....picatinny portable BBQ holding rails and a embossed pic of carlos hathcock on the stock ....then drop a mag in and have the lack of rail width to stop the 18 lb recoil spring from cleaving the bullet noses off on the ramp along with 80% probability of knocking a bullet back into the case and changing o.a.l on every shot ......go figure

oh the suffering ......

ggiilliiee, you've been kind of tolerable of late but this is pure horseshit at it's finest.:uhoh:

Explain to me kind Sir, for I am only a lowly guy in charge of an factory that makes gas piston AR rifles how I can have a rifle shoot like crap then crown the barrel & have it shoot less than 1 MOA??:?

When I say "shoot like crap" I mean like 12" groups! I have had this happen several times until all the barrels we receive are inspected & re-crowned to our spec. No further problems with accuracy.

If it walks like a duck, quacks like a duck then a duck it must be.

Yeah, every now & again we have to suffer your mindless drivel........:tongue:

IronSkegge
September 09, 2007, 02:26
I crowned a 17.5" Imbel barrel tonight, using the marble and valve lapping compound technique. I found a blue marble a couple days ago, so I didn't have to purchase one. The valve grinding compound from Checker Auto was $13 for a package with two tins, #120 coarse and #280 less-coarse.

chrsdwns
September 09, 2007, 12:39
The crown of the barrel is where the rubber hits the road and has a major impact on the accuracy of the barrel.

As the gman says, if you don't get that right the rest does not matter much. It's probably one of the the main reasons why there is so much variation on different mil spec barrels from the same source. For some reason the crown did not always receive the attention it deserves on FAL military barrels

Refacing the crown along with shortening the barrel enough to expose undamaged bore and rifleing is often one of the most usefull steps you can take to restore accuracy on a milsurp rebuild because the crown is often worn or damaged from years of cleaning cleaning or use

The Brownells piloted tool does a good job but any method that gives a uniform perpendicular transition from undamaged barrel bore to ballistic flight is effective. Even a hacksaw and files can do a good job with a skilled and carefull craftsman, it just takes a long time

The 11 degree chamfered face has been shown to be statistically better than a flat surface and it is more resistant to damage in US Airforce testing. Look at a current production DSA barrel to see how to do it right. It's obvious DSA has been doing some back to back testing and FAL accuracy.

4 brigada
September 10, 2007, 10:00
What type of garand barrel and caliber, is it an original, how many rounds thru it, whats the TE. I had a match 308 installed in a bolt gun by all parts and labor it should have been a tackdriver, but I could only get about inch groups, Took it back to my smith and had it recessed and recrowned at 11 degrees it got the groups to half inch so in this case it made a big difference. Might get better deal on a new barrel depending on the answer to the questions. Forgot to give credit I got the 11 degrees info from gunplumber, even though I was in the AF guess they didnt trust us with that info

Cheers

4 brigada

yarro
September 13, 2007, 01:00
The bench rest guys thoroughly researched various degree crowns and parabolic crowns versus flat muzzles and found no difference in accuracy between any of them as long as they were perpendicular to the bore. They did note that it was easier to damage the origin of rifling at the muzzle without a crown. Thus even they crown. Recessing helps protect the rifling even more. There are a lot of poorly cut crowns and less than perpendicular muzzles out there. I have fixed several poorly shooting rifles, just by squaring the muzzle to the bore.

-Yarro

MyTFAL
September 13, 2007, 23:51
How do you spin the marble?