What's up with this 629 PC rifling?

[Petander]

I have had this revolver for a couple of weeks for testing and deciding what to do with it,it anything. I have fed it only FMJ Magtech factory ammo, about 600 rds. The gun is full of problems,a customer return,it is cheap now so I decided I will repair it.

(Being overseas,no S&W warranty here).

Today I decided to switch to my own cast and started to give the gun a serious deep clean first - I have removed copper every 100 rds or so. Well there was lead coming out, a clean VFG plug gets gray stripes no matter what. I didn't use vinegar/peroxide yet. But I already noticed that the previous owner had fired cowboy ammo,there was lead under copper.

There still is lead.

So I took some pics and wow,there seems to be a narrow,little extra groove on the edge of the rifling groove,collecting whatever gets there first.

What is causing this and why?

[Win94ae]

Id take a brass bore brush, wrap a bit of copper chore boy scrubber around it; run it through the bore a few times, then check the bore again.

[Petander]

Id take a brass bore brush, wrap a bit of copper chore boy scrubber around it; run it through the bore a few times, then check the bore again.

It was Bore Tech -clean, both Carbon and Copper removers used. They work great.

Here I added The Dip -clean. No more lead. Look at how rifling starts, rifle groove has an arc profile so it's deeper next to the lands... but the beginning looks strange again.

As if there were burrs in the beginning? But this rifling profile thing,I wonder if this will work with coated cast? Whatever lead there was has been fired last year,commercial cowboy loads. I fired 600 fmj:s after it,still lead.

[slide]

I would send a pm to DougGuy. I'll bet he can tell you. He has dealt with that type of thing a lot.

[Petander]

I would send a pm to DougGuy. I'll bet he can tell you. He has dealt with that type of thing a lot.

Yes, Doug is a forcing cone expert,amongst many other things.

Maybe he chimes in here,I'd rather keep this public.

[edp2k]

Try using something like a dental pick or a piece of stiff bent wire to probe those points in the edge of the rifling and
determine if they are burrs or if the rifling (the grooves) is actually undercutting the lands.

You might also want to use a magnifying glass or a jewelers loop to eyeball things much closer.

[Petander]

It's true I need a better look. Still no borescope... The barrel comes out anyway for a proper installation, it's not clocked right @ 12.

[DougGuy]

You need to recut the forcing cone for sure. And the S&W often is closer to 8.5 degrees it is not 11 which is common. I have a 9 degree cutter that I ordered especially for those, I would order a cutter bit made to 9 degrees from Clymer or someone who makes them. Forget PT&G I cannot work with them any more they are a PITA.

You likely can't fix the groove at the edge of the lands, and powder gas will always bypass the boolit there maybe not so bad with j-words but that will always lead with cast, so that's two strikes against that barrel, what are the chances of getting another barrel?

[Petander]

You likely can't fix the groove at the edge of the lands, and powder gas will always bypass the boolit there maybe not so bad with j-words but that will always lead with cast, so that's two strikes against that barrel, what are the chances of getting another barrel?

I'm afraid you are right,Doug,thank you.

I fired my first 50 cast rounds today and yes, there was leading. More than I like especially with coated bullets...



This pic is after a couple brush strokes with Ed's Red.



Those grooves are really hard to clean. The Dip is nice and easy... but it's like going back in time, my Hi Tek coated bullets do not lead when everything is right and normal. My cylibder throats are also undersize, some factory FMJ:s can not be pushed through by hand.



I still like the gun as a shooter. Clays broke @ 25 meters just fine with cast. I'll shoot 100 rds next time to see if leading accumulates more to affect accuracy.

A new barrel is an impossible dream.

[Win94ae]

Oh my, that is screwed-up, I hope someone can fix it inexpensively. :/

[Petander]

Funny how a timing / sights fix is turning into a complete re-build,on a new gun.

[Petander]

It is leading but after 50 rds I shot this three shot group @ 15 meters.



It's my new "Women And Children Load" , a Mihec 255 approaching 44 Special levels @ 950 fps.




I don't know what to do with this revolver...

[Larry Gibson]

Might just put 100 magnum level jacketed rounds through it.

[Texas by God]

While the barrel is out, polish the forcing cone carefully and I would hand lap the bore. If the barrel was clocked in correctly from the get go, I would fire lap it, but it wasn’t. Good luck, I can’t believe it left the Custom Shop at S&W that way. It must have been a Friday afternoon quitting time or a Monday morning hangover effort

[cub45]

Have you sent all the pics of this gun to S&W and asked them how it left the custom shop like this?

[Petander]

Thanks for posting,everyone. Got a wider hand in the mail today.

Might just put 100 magnum level jacketed rounds through it.

It has 500 j-magnums through it by me now,another 500 by the first owner who returned it to the shop. Lots of copper in the barrel after 50 rds only.

But well, the throats are all around .429" , barrel is at least .4305. I won't be able to see how the barrel shoots with my .432" cast until I ream those throats. Even J-bullets get swaged undersize here,unless they are .428 to begin with.

Is Brownells throat hand tool any good? I see no handle for it?




Another 50 rd box of 950 fps cast... these shoot clean in my -88 m29 with .432" throats...

Have you sent all the pics of this gun to S&W and asked them how it left the custom shop like this?

Cub45 I think S&W is very well aware of their qc.

[edp2k]

Since your in Finland and thus its difficult to send it back to the factory for repair,
I would buy (or borrow) a Brownells forcing cone cutter and re-cut and re-face your forcing cone.

I didn't see any results posted of probing the edge of the rifling with a fine, sharp probe to see if the edge of the lands are actually
undercut or is that just a burr at the intersection of the lands and the forcing cone.

[Petander]

Since your in Finland and thus its difficult to send it back to the factory for repair,
I would buy (or borrow) a Brownells forcing cone cutter and re-cut and re-face your forcing cone.

Yep,I have been thinking about this kit. Funny how a man can go bankrupt with cheap guns. Our Brownells prices are a bit different.

I didn't see any results posted of probing the edge of the rifling with a fine, sharp probe to see if the edge of the lands are actually
undercut or is that just a burr at the intersection of the lands and the forcing cone.

It is both.