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bigh
02-08-2016, 11:19 AM
Can anything be done to repair burrs on the leade of the 22rf chamber without rechambering or re barreling ? The chamber in question has a couple of small burrs from the chambering job, I can see with a Hawkeye borescope where one or two have actually broken off, the rifle shoots decent but not quite what it should, any thoughts?

akajun
02-08-2016, 11:35 AM
POlish them out with some jb bore paste or isso metal polish on a patch on a tight fitting brush. Your smith should have done that in the first place. I only do it on rimfires, centerfires shoot them out just fine, but that small lead bullet doesnt seem to.

bigh
02-08-2016, 12:55 PM
This is a Anschutz factory rifle, I suppose I can give the JB's or Iosso a try I have both, how much do the burrs affect accuracy if they do ?

crb
02-09-2016, 09:55 AM
I use a split arbor and worn 600 paper. In my experience this is way more common than most people think. This is why access to a bore scope is essential to a serious RF shooter. Having your bullet torn up right at the start is detrimental to accuracy.

bigh
02-09-2016, 12:48 PM
Thanks for that info Ray, I agree I have looked at a lot of rimfire bores and chambers and see this more than one would think. I have talked to a RF gunsmith who says he can do it for me.

B.Larson
02-09-2016, 02:36 PM
I use a split arbor and worn 600 paper. In my experience this is way more common than most people think. This is why access to a bore scope is essential to a serious RF shooter. Having your bullet torn up right at the start is detrimental to accuracy.


I agree......... anyone who`s done any sanding to critical dimensions carefully you can get to your goal...... as far as J-B and iosso..... for removing burrs..........no..... they are designed for SUPER lite lapping.......

crb
02-09-2016, 03:46 PM
Once I've removed the burrs I used flitz on a patch to bring the area to a high polish. I call these burrs "boat paddles" because of what they look like when you follow the land back to the burr which flares out from the land.

alinwa
02-09-2016, 07:41 PM
Can anything be done to repair burrs on the leade of the 22rf chamber without rechambering or re barreling ? The chamber in question has a couple of small burrs from the chambering job, I can see with a Hawkeye borescope where one or two have actually broken off, the rifle shoots decent but not quite what it should, any thoughts?

Sometimes the ar chives work..... we'll see

This is one of the latest of many discussions on the subject from 'back in the day, might be something of use. I can't be of any use as I've never dealt with rimfires.



'course the board's a little less friendly now........the tenor has, shall we say, changed....



http://benchrest.com/showthread.php?56756-hob

alinwa
02-09-2016, 11:42 PM
BTW..... this thread (and many others if you can find the old threads....) alludes to "Bill Calfee's book" sometimes in a snide fashion.

Some feel that Bill Calfee is a good rimfire gunsmith.

I am one of these, and furthermore just flatout like the guy.

Others don't.

"The Book" as it useta' be referred to has come to fruition in the ensuing years, all 750+ pages of it, and of coure I, being me, have a copy and enjoy it.

But in any case Bill does use a 'hobb' to address the problem broached by the OP in this thread, and in his book he details it's use. Take it or leave it, I'm all done arguing with the sort of folks who drove Bill from this board, the throat on a Bill Calfee rifle is a work of art.

Fact.

And as my buddy Jesse sez..."Ya' Cain't Argue With The Facts" so I will state a fact from 'The Art Of Rimfire Accuracy' as I read it.

Bill Calfee essentially irons or peens his throats into shape using a hardened rod ground to mimic the contour of the bullet of choice. He's used many different methods of application but ONE method he writes of is to chuck the barrel in the lathe, spin it at about 40-80 rpms and use the hob to gently TAP-tap-tap-tap into the leade area.... followed by using lead laps and very fine compounds to polish the throats to shiney mirror-looking finish, hand fitting them to the shape desired. Then he sez it still takes a couple thousand rds in some cases to season in...

Worthy book in my opinion

Not A Fact


al

alinwa
02-09-2016, 11:46 PM
Melancholy Moment....

"Man, nearly everyone but me from that 7-yr old thread is dead or gone"

Big Al and tim.....and sometimes me :)

Dusty Stevens
02-10-2016, 01:26 AM
If calfee tells the whole story you can take that to the bank its a good method. I dont think anybody can argue with his success!

crb
02-10-2016, 07:49 AM
Every bbl I've ever cleaned up with the split arbor immediately shot much better than it did before. Typically the bbl with burrs will shoot pretty good but throw 8s and even 7s out there with no warning. After getting rid of the burrs a bad miss would be a 9 that wouldn't plug a 10 [ RBA target ]. This of course doesn't count the 9s and even occasional 8s from the flags jumping over just as you pull the trigger :p

tim
02-10-2016, 04:40 PM
BTW..... this thread (and many others if you can find the old threads....) alludes to "Bill Calfee's book" sometimes in a snide fashion.

Some feel that Bill Calfee is a good rimfire gunsmith.

I am one of these, and furthermore just flatout like the guy.

Others don't.

"The Book" as it useta' be referred to has come to fruition in the ensuing years, all 750+ pages of it, and of coure I, being me, have a copy and enjoy it.

But in any case Bill does use a 'hobb' to address the problem broached by the OP in this thread, and in his book he details it's use. Take it or leave it, I'm all done arguing with the sort of folks who drove Bill from this board, the throat on a Bill Calfee rifle is a work of art.

Fact.

And as my buddy Jesse sez..."Ya' Cain't Argue With The Facts" so I will state a fact from 'The Art Of Rimfire Accuracy' as I read it.

Bill Calfee essentially irons or peens his throats into shape using a hardened rod ground to mimic the contour of the bullet of choice. He's used many different methods of application but ONE method he writes of is to chuck the barrel in the lathe, spin it at about 40-80 rpms and use the hob to gently TAP-tap-tap-tap into the leade area.... followed by using lead laps and very fine compounds to polish the throats to shiney mirror-looking finish, hand fitting them to the shape desired. Then he sez it still takes a couple thousand rds in some cases to season in...

Worthy book in my opinion

Not A Fact


al

Any curious soul can and probably should search out the fact that it has been a good long while since your guy has, in fact, finished a chamber with that methodology.
As a point of fact, nobody drove him from here except the proprietor. Just cause, I believe the term would be.

mwezell
02-10-2016, 06:05 PM
Any curious soul can and probably should search out the fact that it has been a good long while since your guy has, in fact, finished a chamber with that methodology.
As a point of fact, nobody drove him from here except the proprietor. Just cause, I believe the term would be.
..or just because he wanted to...which I support.:cool:

tim
02-10-2016, 06:09 PM
..or just because he wanted to...which I support.:cool:

Well I suspect you'd agree Wilbur is a pretty patient guy, gives us a lot of latitude, but everybody has a limit.

mwezell
02-10-2016, 07:21 PM
Well I suspect you'd agree Wilbur is a pretty patient guy, gives us a lot of latitude, but everybody has a limit.

Yes sir, I would.

crb
02-11-2016, 01:42 PM
Somebody explain to me how you remove burrs on the side of the lands with a hob .

Dennis D.
02-11-2016, 02:34 PM
First you have to gather magic fairy dust and unicorn fluff to sprinkle on the hob. From there it's all self explanatory.

I think folks have gotten the wrong idea of what the "hob" actually does. Even Bill C. says he does a post chamber lap to clean up any lingering burrs.


Dennis

Wilbur
02-16-2016, 11:39 PM
Bill wanted to post anything and everything regardless of who it hurt. I tried to arrange some kind of thing where he could do that but it just wasn't in the cards. Did I want Bill Calfee posting here? Heck yeah I did!

crb
02-17-2016, 09:29 AM
It seems like there are way more contentious personalities on the rimfire side of the game as compared to the centerfire side. At least on the internets. Never seen anything but super nice people at matches.