doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Question about reaming chokes

Anyone with experience with the "Walker" choke opening method (adjustable reamer and T-handle from the muzzle end unpiloted (except by the reamer blades). Can anything be accomplished this way besides making a mess and changing the POI? Brownell has this system and the bore piloted system and as usual the riskiest is the cheapest. I want to open up a Merkel 200 both barrels. I believe the choke is taper all the way (no parallel after) and not talking a few thou here. It may go to Mike Orlen in the end.

jack

-Hi Jack--I have done a lot of chokes all from the back end -never from the muzzle end-i don t believe a proper job can be done from
the mussel-find someone you trust that has experience-it well be
cheaper in the end
Sydney

if you are talking about going from full and fuller to ic/mod let a smith have at it... grinding away on those Merkel barrels yourself is just asking 4 trouble...

Years ago I let a hillbilly gunsmith muzzle grind the chokes in a Browning BSS. When he was done the right barrel shot high and to the right, the left far to the left. I'd give it to somebody that's an expert like Merrington, this is not a do it yourself kind of job.

Destry

Thanks guys. I need to be hit over the head every so often to avoid the attraction of risk for its own sake.

jack

I have done several from the muzzle, with a piloting extension I made my self. None have been off by much on POI. I now use the rear entry method, using the piloted long rod sold by Brownell's. I agree it's the better way but not the only way.

I have used a "modified' Walker method for a number of years now.
It's just not rocket science. I have used this "from the muzzle" method quite successfully - as witnessed by the patterning paper after the choke opening. The "from the breech" method is much more professional and mistake-proof, but the "from the muzzle method" can be used successfully IF YOU ARE CAREFUL AND TAKE IT EASY. Once metal is cut and gone, IT'S GONE. Think a lot before you cut. I suppose it would be possible to do the job without my Skeet's Bore Gauge, but it would involve quite a bit more travel to/from the range to confirm how much I had opened the choke after each metal removal session. Much easier to use a device such as my Skeet's Bore Gauge to measure (in thousands of an inch) how much metal has been removed.
I figured immediately on reading Walker's article that his having the work initially held horizontally was bass-akwards, as it would seem to introduce a whole bunch of inaccuracy in trying to keep the cutting tool parallel with the bore.
I hold the barrels vertically in a padded vise, muzzles up for the entire process. Keep in mind that SxS shotgun bores are NOT parallel. Each bore must be plumb up and down in the vise. I use a LARGE T-handle, at just below eye level, to drive the expandable reamer, and ENSURE the T-handle is as horizontal as I can eye-ball it. I let the weight of the T-handle and the reamer control the "rate of feed". I keep the expandable reamer well lubricated, and withdraw and clean the cut metal bits from the reamer's cutting edges (with toilet paper and a jeweler's screwdriver) and then re-lubricate, and repeat the process. I only rotate the reamer several half turns then withdraw, clean and relube. Then re-measure with your bore gauge. Repeat the process as required. As I'm a hobby-gunsmith and RETIRED, I can afford the time to nibble away at the job - a gunsmithing business could not afford the time to do it my way.
When the desired diameter is achieved, I change the barrels in the vise to horizontal, to remove the cutting tool marks with a brake hone (if necessary), then polish with a flex-hone.
Job done.
Those shotguns with a parallel length forward of the choke will guide the reamer straight down to the choke with no problem. Those shotguns with chokes that are a simple cone toward the muzzle require that you PAY A LOT OF ATTENTION TO KEEPING EVERYTHING PLUMB AND THE T-HANDLE PERFECTLY HORIZONTAL.
I guarentee nothing - except that this modified Walker method has worked many times for me. I work on my shotguns to PLEASE ME. I do not voluntarily work on other folk's shotguns - but I have had my arm twisted several times.
I found that the metal in my Fox, Parker and LC Smith guns all cut reasonably easily. My Browning Superposeds had much different metal in the barrels and took some effort.
I don't recommend this method to other people, but offer this information FWIW, as it is what I have done, and it has worked for me.

As a retired machinist with 35 yrs experience I will say this, take it for whatever you feel its worth; The Walker system will generally give good results on those chokes "With a Parallel". You only take very light cuts & the reamer will generally follow the existing bore.
"If" on the other hand you try it on a taper choke (No Parallel) & it stays straight with no shift of impact rush straight out & buy "ONE" lottery ticket, anybody that luckey only needs one.

For the beginner to open choke from muzzle allmost impossible. Send it to Mike now.
Or try it yourself for your own risk from breech end.
http://www.youtube.com/watch?v=l7YQf6YWLaM

I have been able to change the POI on some unregulated barrels by attacking it from the muzzle using a wooden dowell with emery cloth wrapped around. It removes very little at a time and I could apply some pressure to remove more from where I wanted it to. I checked the results often at the patterning board and followed the muzzle access with a breech access to finish up the job. Crude process, but worked ok for me.