S&w 625

[Pistolero]

The saga continues.....
Pulled the S&W 625 barrel this afternoon, and then just for grins, turned the barrel back as far as it would go hand
tight. 45 degrees short of clocking up for the front sight. Yikes! Here is a pic of it before anything was done.


Took off 0.001 from the bbl shoulder, and checked again, did about 15 deg better. Here is what 0.001" trim
on the shoulder did for the clocking. And there is a target, one of the better groups......with a huge flier.


So, took off another 0.001", a bit better. Another 0.0006" (DRO is very handy) and we are getting close,
so take off 0.0004" and it is just a couple degrees short of lining up the front sight when hand tight.
Here is a look at the frame and barrel junction when it was considered done, hand tight.



Blue loctite, and snug it up to align the sights just straight with the grip frame. Pin gauge shows perhaps
0.0005" or less residual choke, but a close look shows a trace of lead, will scrub a bit more with a Lewis Lead
Remover and see if it is all gone or whether it will need a tiny bit of firelapping. Hope not, I am not a big
fan of firelapping, but know it can be a good thing if you have to do it.

Will see what Mr. Target has to say.

Oh, darn.....can Brad or someone fix that lower case "w" in the title, please.

Bill

 

[Brad]

No photos of the lathe setup?

 

[Pistolero]

Well, I have an older one.....same old.

Here is a pic for the Thunder Ranch Model 21 with 0.004" thread choke.



Aluminum spud turned to groove diam, tapped into the muzzle. The first time you use it, the
threads broach the aluminum, hurts nothing. The threads will drive the barrel. The other end
is on a live center.

Bill

 

[Brad]

Interesting setup. I need to try that someday.
I have a Ruger BH in 357 that is getting a new barrel one of these days.

 

[RicinYakima]

You are doing fine work! Are you taking orders to fix others? People want to know.

 

[Pistolero]

Not a chance of doing others. Barely can do my own stuff! I need a whole
truckload of round-tuits just to get the my own stuff that need doing. And actually,
that is a friend's work, I do not have the correct frame wrench for an N frame, only
made one for K-frame. Another thing to do is make the frame wrench inserts for
the N-frame.

Brad - a new barrel or just the choke removed? Most will spring back, even the ones that
don't go almost all the way, can fire lap out the last residual choke usually 0.005 or 0.001.
Most spring back all the way.

Bill

 

[Brad]

This will be a whole new barrel. Bought the gun used, bore was full of lead. Cleaned it out and discovered a ring at the front of the frame. Bet it was a cowboy action gun and had a live round fired after a squib.

Plan is to make a longer barrel and see what it does at ranges put to 100

 

[Pistolero]

Get a Douglas blank, they are affordable and really good quality. And
get faster twist than the standard S&W uses. Not sure what Ruger uses,
but S&W is marginal. OK, one online source says Ruger uses 1:18.75" , I'd
go faster than that for sure. I'll check with my expert who has done this many
times and see what twist he recommends. I think he has told me he goes to
1:10, but that is just from memory. I think S&W uses a pretty similar twist,
and likely is really too slow.

Bill

 

[358156 hp]

I believe Colt used 1:14. Give me a minute and I'll calculate the RPM for you, what distance will you be shooting it at?

 

[Pistolero]

I think Brad will be mostly using it at 300 yds.

Bill

 

[CZ93X62]

You guys are on a roll this morning.

 

[Bass Ackward]

I'm lookin down that bore pic & it looks like conventional rifling. My JMs have the octagonal & conventional on top of that. My 5" custom shop job has conventional cut rifling like the olden days. What is it Bill?

 

[358156 hp]

You guys are on a roll this morning.

We're here all week folks, and two shows on Saturday.

 

[Pistolero]

Conventional cut rifling, not the two piece barrel with the EDMed bore. Never heard of the
"octagonal & conventional on top of that. " before, strange.

I loaded up some ammo and took it to the range, even though the weather was not
good. 25F, in and out clouds making the light very changeable, and very windy and
gusty, 25 gusting 36 was the aviation call. In Kansans? How......normal.

In any case several groups were not great, 3" range, but I tried some commercial LRN 230s that I
had, just for grins, and a medium load of 4.8gr TG, Rem .45 ACP brass, Rem 2 1/2 primers.
THAT one, it liked.



About 7/8" for five shots at 25 yds will work for me. Left top is a double, right hole is a double.

Gotta try that one again.

Bill

 

[oscarflytyer]

so... Bill, think I am missing something... Is this a/the NEW 625 you bought? And having to do something with the bbl? I am a tad confused (NOT hard to do!). Asking, as I am looking to get the new 625 JM... Thanx

 

[Pistolero]

New to me, looks to be barely shot. The barrel, as many current production and last 25-30 year revolvers to,
it had a significant thread choke in the barrel. Pulled the barrel, faced off the shoulder to reset it without\
the thread choke - which comes from overtightening.

Throats are perfect at .452, barrel is cut rifled, not the new EDM insert barrel, a plus IMO and all is beautifully
made, timing is spot on, single action trigger is exceptionally good and the front sight is easily changed to
suit your needs, no tools. Like the gun, not the barrel choke, will do a mild action job on it later at my
leisure, it is pretty decent now, dbl action normal level, higher than I like, so I set up mine lower, when
I get around to it.

Picked it up from FFL, to the range that PM, not good results, lots of 6-8" fliers and 4-6" "groups".
Pulled the bbl and fixed it the next day, shot it again the next day, after the loctite had cured. I have
owned it about 4 days now, just came up from the basement loading some more test loads.

This is a JM model, and that 7/8" group is what I was looking for not a lot of guns will do that, EVER.

Bill

 

[oscarflytyer]

so not a "brand new" 625... Reason I am trying to nail it down is that I am considering buying a brand spanking new one (wouldn't, except that I have a gift cert with very narrow limitations on it...). And IF I get a NEW 625 JM, want to make sure out of box it will work well with cast, etc... I do NOT want to spend ~$900 and have a project that I have to put another $200-$300 just to be even reasonably happy...

PS: I nearly NEVER buy new guns! Like Old! AND def NOT a cutting edge guy when it comes to new gun fads.

 

[Pistolero]

Band new means nothing in this case. Not like it got broken by the other owner, it was screwed up at
the factory. I like new guns but have bought many brand new S&Ws, including a pricey Thunder Ranch Special
with a cool gold inlay.....and a 0.004" barrel choke. My first Mtn Gun .44 Mag was fine, my 586+ seven shooter
.357 Mag is perfect, a real tack driver with cast, zero leading, ever. Bought about 8 years ago. They vary.

I love S&W revolvers, but I do wish they would stop screwing in the barrels too tight.
The most recent S&W I bought which shot cast perfectly "right out of the box" is a 1926-build N-frame
44 Spl. Not meaning to rain on your parade, buy it, but do not be surprised if the barrel has significant
choke, many do.

Bill

 

[Bass Ackward]

Conventional cut rifling, not the two piece barrel with the EDMed bore. Never heard of the
"octagonal & conventional on top of that. " before, strange.

Well I lied.

One 4”er IS a JM. It has the EDM with conventional rifling on top. Getting that to photo well enough to see, but if you look at the muzzle (5:30) you can see the height. The other 4”er, is just a 625-8 (although it came with the JM wood on it). It has the straight EDM. Wasn’t EDM the process? See pic 2. It just has a flat on top of the .... rounded land. Hope you can see. The pics may be flipped. Oh boy.

 

[Pistolero]

Hmmm, can't really see well in the pix. The EDM process produces an angled or rounded profile on the sides of the
lands, while cut rifling has square corners on the lands. I can see the wider lands that you have in the
pix, seems like normal EDM, but not sharp enough pic to be sure.

Electrical discharge machining uses a "cutter" which is connected to a high voltage power supply which
creates a pulsating voltage, and it 'sparks' to the work piece, each tiny spark removing a tiny bite out of
the work piece. As the work piece is cut away by these rapid, huge quantity of sparks, the cutter moves
ahead, continuing the cut. A common form is "wire EDM" which the wire acts like a band saw, although it
never actually touches the piece of steel being cut. This 'no contact' cutting means the work piece is not
distorted from cutter forces, so thin work can be cut with no distortion. Cutting is done submerged in a
coolant fluid.

If you are old enough to have refiled points on car ignitions, the wear of the tungsten points was
due to electrical discharge every time the points opened.

EDM cannot produce tight corners easily, so the land-to-groove transition is rounded or angled.
The surface finish is slightly matte, but quite nice.

I am not convince whether I like EDM barrels or not. The don't seem terribly bad, but I am not sure
the surface finish is as compatible with lead bullets as cut rifling. But, IMO , the jury is still out.

Bill