Gunsmith Input: Revolver Barrel Crown?

[MrUnderwood08]

I have two revolvers that I believe need to be refaced and re-crowned.

First is a recent production Smith 625-8 JM. The Crown is obviously uneven and shows chatter marks. I love the model but I think I got one that missed Quality Control. Or maybe it represents S&W market focus current standards.

The second is a Ruger GP100 that is probably 8-10 years old. Face is rough and visually uneven. Looks like it was pushed by hand against a belt sander.

What is the correct way to reface or crown a barrel on a revolver? How about forcing cone work? I have access to lathe and mill. Rifle and semi-auto barrels could be removed and chucked into a lathe to accomplish the task. How about a revolver?

1. As I understand it, disassembling frame from barrel to chuck into a lathe could do more damage than any accuracy work on the barrel might accomplish. Is this true?

2. Keeping frame and barrel intact, Would centering it precisely under the mill spindle and using a correct chamfer mill and fly cutter or other tool be the preferred method. Could the forcing cone be done in a similar fashion?

3. Or is using the brownells kits with pilots and cutting by hand preferred/good enough?

I did search. I understand I could bring to attention of the manufacturer. I understand I could leave it alone and shoot as is. What I'm looking for is a GOOD qualified gunsmith to explain what right looks like. Pictures to follow.

 

[rbert0005]

Brownells sells a crowning toll. No need to take the barrel off.

Bob

 

[MrUnderwood08]

Thanks Bob. That would be the 3rd option above. Have you used the tool? Is it the best method?

 

[rbert0005]

No I have not used one, but I can't imagine it would be that tough.

Patience would be in order.

Bob

 

[sac-gunslinger]

How are the two firearms performing? This should be the basis for deciding on work that needs to be done. If they shoot fine you may not need to do anything. You can often screw things up worse by trying to make them perfect (don't ask me how I know).

 

[bhbaxter]

The Brownells tools are easy to use and come with instructions. I have been using them for years and would be happy to talk you through the process if you call. the hand operated tools follow the center line of the bore using a precision mandrel and do not locate from the outside surfaces of the barrel which may not be concentric.I'll PM with my phone #. Dave

 

[MrUnderwood08]

625------







GP100---- Width of face does not look uniform. Narrower on top/right of photo, wider on bottom/left.

 

[bhbaxter]

The critical part of the crown is not the sanded area you are calling the face but the beveled area that touches the bore.I would recrown both of them. The critical aspect of a crown is when the bullet's base leaves the bore and the high pressure gas vents around the bullet. If it is not equal on all sides it will tilt the bullet and lead to inaccuracy. Dave

 

[05CarbonDRZ]

The crown on the 625 is just terrible,I would make the Factory recut it.There is no reason something like that should ever pass QC.

 

[wproct]

I agree the crown on the 625 looks bad, not sure I see the problem with the GP100?

 

[Bat Guano]

A few years back I picked up a M66. It turned out to have barrel issues; the barrel was canted a bit which threw the POI off, and the crown showed evidence of cleaning rod wear and was a bit egg-shaped. S&W turned the barrel to where it should have been but it was only later that I noticed the bad crown.

I already had the Brownell's charge hole chamfer cutter, so got a barrel pilot and went after the crown by hand. I had to go a bit deeper than the typical GP-100 but did get all the "egg" out. It was a bit of a nervous operation but it turned out fine. The upshot is that the gun became a very good shooter. (There were no more M66 replacement barrels to be had so I had no alternative.)

 

[cal50]

I cut a clean 11 degree crown & polish it up especially where it intersects the lands & grooves. A bullet needs a clean exit.

 

[rwsmith]

I cut a clean 11 degree crown & polish it up especially where it intersects the lands & grooves. A bullet needs a clean exit.

That's beautiful work.

 

[riverrat38]

cal50
Tell us more!
Was the work done with hand tools like the ones Brownells sells>

Thanks,
Rick

 

[cal50]

cal50
Tell us more!
Was the work done with hand tools like the ones Brownells sells>

Thanks,
Rick

The Brownell's tool actually works well, my friend has a couple of them. I have a lathe and a mill and borrowed my friends action wrench when I shortened my 625 5" into a 4". I cut the crown with a boring bar at the desired angle then polished it up.

Those factory crown pictures are a total embarrassment and something that obvious should never have left the factory or passed QC IMHO.


When removing a revolver barrel the frame need the support from a proper wrench. The other wild card variable on interference fit barrels is how much torque was used when the barrel was cranked on. If someone REALLY cranked it on some frames have been cracked on older guns trying to remove them. I have not heard of this on newer gun so maybe someone that has worked on the latest and greatest can chime in.

My 500 uses the 2 piece barrel and since I wanted to shorten it I used my band saw to remove it. I shortened the barrel shroud and made a front end nut for a 6" / 500 Mag.

The Brownell's tool can fix a horrible crown / chamfer but I would really send that back to S&W on their dime and have them replace the barrel. The crown is horrible and the front sight marks looks like Ray Charles tried putting the sight on it.

http://smith-wessonforum.com/s-w-re...311636-peek-inside-s-w-500-barrel-shroud.html

 

[H Richard]

I had a friend re-crown a rifle barrel for me, and it was done with the hand-held tool from Brownells. With the pilot, it is very easy to do, and If I had had the tool I would have done it myself. Just use a little cutting oil with it.

 

[BLUEDOT37]

625-8 PC re-crown

After being disappointed with my newly purchased 625 PC's crown, & a few of my older revolvers too, I decided to purchase what I needed to re-crown them from Brownell's.

Here's before & after pictures.

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625-8 PC, barrel crown, before: - (thin, shallow & off-center)

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625-8 PC, barrel crown, after: - (the original off-center crown limited how wide I cut)

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Brownells Chamfering Tools

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Brownells Chamfering Tools

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