Crown question

M

MightyMouse

New member
I cut my first crown today on a old heavy 10/22 barrel I had laying around for practice before doing one of my .22lr benchrest guns, and had a couple questions, will polishing after cutting do anything for accuracy or just appearance, and is the transition from rifling to crown sufficient with the 11* cut into the bore or should the edge of the rifling be tapered to the 11* crown?

I tried to take a couple of pictures there not great, crown is smoother than it looks in picture,
Thanks in advance

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do a search on this forum..recent topic.
the only thing that really matters is the short transition from bore to muzzle face.
 
For my own competitive use and sport I need to have a polished face. So I back cut a 30 degree relief just beyond the bottom of the grooves and use a QTip to check for burrs. Then carefully polish the face as that area is not affected by the polishing process and does no harm to the crown the way that I go about it . The face is also cut at 90 degrees to the center line of the bore and I hope that makes sense.

 
I read a bunch of old threads on crowns, most seem to say a flat, recessed, or 11* crown makes no real difference, but they seem to be split on leaving the bore to crown sharp with no burrs or putting a chamfer in the bore to transition the bore to the crown. Currently I have a sharp bore to crown with no burrs, it passes the q-tip test and with my bore scope I see no burrs, if the weather would cooperate I'd just go shoot it.

Louis, can I ask what you need the polished face for, is it more of a centerfire thing, I'm only shooting rimfire.
 
I am a competitive singleshot falling block cast bullet competitor and the polished face is so I see the lube star left by my hand cast and self lubed lead and tin bullets. If the star is not per-say perfect and easily seen it tells me a few things one and the more important is if I have actually crowned it right or if it needs to now be re-crowned. I also do not let my cleaning patch ever exist the bore by doing so it can create the damage that would require a re-crowning in very short order and I also use a Parker Hale jag so the patch is wrapped and easily brought back through the bore and it also keep the jag from touching the lands.
 
I think Mr. Louis makes a very valid point. I too shoot cast, and they definitely leave signature on the crown. I pull a beveled crown on all my barrels, I use a brush when cleaning and it doesn't make sense to me to pull a brush over a sharp crown. As long as it is indicated properly, and burr free, it works fine.
 
I cut a 60 degree bevel on an indicated bore with a boring bar on my benchrest rifles and my hunting rifles. Whether the crown is flat, 11 degrees, 15 degrees, recessed counterbore or any other configuration, I haven’t seen it make any difference. The most commonly used benchrest crown is the flat crown with a sharp edge at the bore. If I thought it was better, I’d use it. I don’t. I think it’s a short lived crown and will need to be recrowned frequently. The crown with the 60 degree bevel barely deeper than what it takes to get a slight ring around the bore will last for the life of the barrel. That’s my story and I’m sticking to it. It is burr free and I check it with a cotton swab after cutting it.
 
and you cut from the inside out, correct ?

Mike Bryant said:
I cut a 60 degree bevel on an indicated bore with a boring bar on my benchrest rifles and my hunting rifles. Whether the crown is flat, 11 degrees, 15 degrees, recessed counterbore or any other configuration, I haven’t seen it make any difference. The most commonly used benchrest crown is the flat crown with a sharp edge at the bore. If I thought it was better, I’d use it. I don’t. I think it’s a short lived crown and will need to be recrowned frequently. The crown with the 60 degree bevel barely deeper than what it takes to get a slight ring around the bore will last for the life of the barrel. That’s my story and I’m sticking to it. It is burr free and I check it with a cotton swab after cutting it.
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Myself I do cut from the inside out and if you cut from the outside in you will probably push a burr into the muzzle. I also use a boring bar type looking tool that I ground.
 
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Whick Model Win 52B

Bill:
Are you referring to the original Win 52B's or The Reproduction from Japan?
 
Allot of the F Class shooters in my area use a flat crown and as has been mentioned they will be re-crowned usually when being setback once and re-chambered.
 
billbrawand said:
for everyones ifo a win. 52 b triger can be replaced with a d triger i had mine done.
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sheckengross from by dayton pa. Karl kenyon called me when he dd my 2 ounce trigger said he had never seen that done before in all his yrs.dave bruno of dayton may be able to help anyone find someone to do this.
 
A perfect crown does not do all that much,
but an imperfect one will really screw up groups.

A decent amount of the arguing seems to go back
to finding a simple setup that reliably creates
'good' crowns each time.

Unless you are mass crowning rifle barrels, few can
afford to have lathes dedicated to a single function.

The Shilens of the world have that advantage.

The rest of use set up each time we need to crown a barrel.
and this is when simple starts showing its advantage.

In 'one off' machine work setup time is what eats your money.
 
I have a set of piloted cutters

that will cut a decent crown but having a lathe, I don't use them. I have used them in the past and they work fine, or seem to at least.

Pete
 
cut a crown, or face the muzzle ??
i still say it is 2 different things, that MAY be done at the same time
not my style
Pete Wass said:
that will cut a decent crown but having a lathe, I don't use them. I have used them in the past and they work fine, or seem to at least.

Pete
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