recutting chamfer in the muzzle

[deerspy]

I shot a old 243win to day bullets were making holes .240 by .320 in the paper. took it home and looked at crown with magnifying glass and looks like I need to re cut chamfer , what kind of tools can I buy to due this with, it seams a countersink with a pilot should work where could I by one, or would it be cheaper to find a gun smith to touch it up?

[country gent]

How bad is the crown? Is it just the Crown/ Chamfer or is there also cleaning rod Damage to the muzzle? If not real bad a brass ball and lapping compound can be used to clean it up A round head brass screw will work also. Manson reamers makes a tool for cutting the crown, Brownells has tools to do it also. Midways may have a tool also.

[nicholst55]

You can recrown it with a ball bearing and some lapping compound, as far as that goes. Far better to have a gunsmith do it on a lathe.

[johnson1942]

i have a complete set as you discribed from brownells. ive done about 20 or so rifles i feel better than a lathe. the crown is very important. when i use the brownell cutter with pilot i finish with a piece of 200 emery paper with a hole punched in and slipped over the cutting surface of the cutter. the paper back is to the cutter so no damage to it, i progress to 2000 grit and it is perfect and looks like chrome. if you live in the remote contry you can look at your crown before and after it is done in this way. remember you have to live remote like i do. no one lives behind me and absolutly no one is out their and their is a high hill their also. average ranch is 10,000 acres in this county. just dont want a naysayer saying im dangerous when im not. have some one fire the gun safely when it is pitch black dark out. the fire ball should be perfect with no fingers or misshappen in any way. a perfect crown will do that but a bad one wont. forgot to say stand back some and to each side and look carefully at the muzzle flash. a bad crown is not hard to spot as is a good one. a bad crown can push the bullet off crooked. also check the length of your bullet against the twist, it may be too long. maybe handloading a shorter bullet will solve your problem. if you think it is remote here the county 20 miles west of me the average ranch is 100,000 acres. drive ways are measured in several miles. makes for peace and good air.

[deerspy]

thanks for the ideals, it is bad enough that I think it needs to be cut about .005 to .010 deeper to clean up looks like some one may have hit it on the ground or rocks it has a raised place in one grove and another looks like something has been banging on it. that chamfering tool that brownells has looks like what i need but did not want to spend 100.00 + ship looks like it take about 10 minuts to fix maybe I can find a smith to due it for less. I might go to tool store and see if they have cutter with pilot I wounder what size pilot needs to be?

[johnson1942]

brass one,snug fit. if it is a little undersized wrap carefully with paper as paper is a really good shim.im surprised at the price but i got mine years ago so that accounts for the diff. in prices.

[oldred]

The pilot needs to fit the bore as closely as possible without being a tight fit, it's highly unlikely you will find such a tool anywhere except for specialized gunsmithing tools. The damage you describe sounds like it's way more than the ball bearing/brass screw trick will work for and it's very possible that the muzzle may need to be cut back a few thousandths, not a big deal at all with a lathe but a bit more complicated with hand tools. Be VERY careful using a piloted hand tool and make SURE it's the proper tool made for doing that job because the wrong type or size of the pilot could do serious damage to the rifling to a depth the pilot might reach, this is not of much concern with the right tool made for the job but if you improvise with something else be aware! Also if you finish with lapping compound make SURE none of it works it's way down into the bore if a screw is used, probably not a problem with a ball bearing however and that's why I prefer using a bearing for this.

[johnson1942]

also you can cut a new crown useing a small square amd a file. go around and around with the square and fileing a little each time, you can get it perfect. you take the sharp edge off of the bore with a piece of wet sanding paper stretched over a small ball bearing of something round. push it unto the muzzle and slowly rotate untill the sharp edge is gone. also after you have filed it square with the help of a square, cover the file with 220 paper and work up to very fine paper and it will look like chrome.

[Denny303]

this is good info, I have a trapdoor I have to recrown cause someone took a hacksaw to it and lets just say its less than square lol, any tips on cutting the barrel back an 1/8 or so using common hand tools? i presume a hacksaw would work the best?

[country gent]

Denny start with a medium / coarse long cut lathe file and work square to a good square then a fine file to finish smoother, also fillyour files with chalk to prevent pinning sand paper on a file to desired finish break sharp edge on outside and polish /crown with ball and lapping compound. Look at the edge with a magnifying glass and when there is a nice "ring around the bore with now burrs showing your done. I dont spin the ball per say but work it in a figure 8 pattern, start slow with the pattern and soon youll be able to speed up the movement rotate barrel 1/2-1/4 turn every 6-8 complete 8s The figure 8 pattern keeps the ball round and even, dosnt let a ring be cut in it.

[Denny303]

thanks gent, I think ill be able to do it, would valve grinding compound be too coarse to finish with? im trying to use things I can buy locally.

[johnson1942]

a square and a file as we suggested gives a perfect muzzle. the ball i put on a board on the floor. then the emery paper over it. then i put the barrel with muzzle down verticle between my knees with me sitting in a chair onto the ball with the emery paper over it. i just rotate the barrel slow over this and the edge is camphered perfect and shinny and smooth. just use the weight of the gun. they come out perfect and usually better than from the factory.

[country gent]

Valve gringing compound is fine then flitz or a fine polishing compound to finish with. I normally finish with yellow diamond compound but any "fine" lapping compound, rouge, or metal polish will work also. Another thing to do is write down what dia ball the crown was done with where you will be able to recover it. When it comes time to touch it up having the right ball is much faster and easier than starting with a diffrent one.

[deerspy]

A friend said to watch Larry's videos at Midway USA and see how he does it there are about 4 different videos there my friend said he has all the tools to do it so I am going there to morrow thanks to all for you help.

[Denny303]

thanks guys, your the best. will upload pics when I get her all fixed up

[David2011]

If the crown is cut on a lathe from the center to the outside with a good sharp tool I am of the opinion that I am finished at that point. The rifling is crisp and perfect. I don't believe I can ever use brass bolts, sandpaper or steel balls as accurately as my lathe cuts a muzzle. I also have the Brownell's 11 degree tool and some pilots but my preference is to crown a flat or recessed crown on the lathe. The 11 degree cutter does a good job but it requires a fine touch to use without leaving any marks on the muzzle.

You might find a machinist to cut a new crown even if he is not a "gunsmith." Most gunsmithing only requires a small machining skillset but most any real machinist can handle gunsmithing tasks. Definitely only use gunsmith supply tools if you decide to do it yourself.

David

[MtGun44]

I use the Brownell's 11 degree crowning tool with pilots. Works very well.
I have found many crowns that looked just fine but were not concentric.

Bill

[johnson1942]

mtgun 44, you are right, many look right but are not, thanks for your post

[deerspy]

got it done with hand tools they were just machine cutters ran by hand, it could not be put in lathe, can't wait to try it out and I should be able to get to range in the next week or so hope I don't get any more elongated holes and a 1 inch group would be nice!

[johnson1942]

again to be redundant, if you get elongated holes go to a shorter bullet, that would most likely cure the problem. however the way you described your muzzle it was really banged up. when we hunt deer and do a lot of driveing around in the suv my son and i always put thick wool scocks over the muzzle of our guns. we never have a gun in the suv without a muzzle protector. a heavy wool sock that can be slipped off fast.

[deerspy]

got to try out new crown on the Win .243 and I think I fixed it would be a nice group except for the flyer to the right, no more elongated holes now just need to practice more.
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