stole a bison chuck on ebay!

NIB: $20 (+$19) shipping.

The only other one I saw was used, and $450. No idea why this one was cheap, but it looks fantastic.

There seems to be a 2 3/16 10TPI back that will fit it at: http://brassandtool.com/Backplate-Adaptors.html so we are close to liftoff.

Got the Hardinge Toolroom Quick Change lathe!

The hardinge lathe I bought last week finally showed up. The shipper had go use three different people before the final guy (a retired merch mariner) succeeded. He had to drive it up here since none of his employees wanted to deal with it.

According to helpful people on practical machinist it was made in the 1930s. It looks like the toolroom lathe on Tony's UK lathe site (http://www.lathes.co.uk/cataract/page5.html), but not quite as clean.


It was converted to 110v using a baldor motor. Theres a lot of tooling --- several live centers, collets, 3 and 4 jaw chucks, even comes with a spare baldor! According to the mover guy it looks like the owner built race cars --- you can see it was used for some heavy work from a few of the enormous tool bits. Seems like it may be sturdy enough for anything needed.

There's a couple of problems. First I have no manuals. If anyone knows of any writeups for how to use and care for one of these I'd be really happy to hear about them. Second I have to replace the belt. The mechanism the motor uses to rotate the belt (and thus the spindle) has a chunk missing on the outside. And a couple of screws seem missing from the spindle area. But, other than that, it's a very very good buy from what I can tell. The controls are lovely in person.

Spindle type seems to be 2 3/16 10TPI.


On the truck: the driveway is very steep, just missed bottoming out by 1 1/2". The lift gate wobbled like a boat bringing the lathe down: it's much heavier than it looks. They did not skimp on the iron:

Using screw extractors to fix bull barrel python

Thanks to some helpful suggestions, I was able to extract the broken screws on the bull barrel python discussed here: http://coltpython.blogspot.com/2009/07/fixing-misfires-in-41-mag-python.html

I went to OSH and get a couple screw extractors, used a drill, and the broken screws came out. And it was pretty easy.

Here's the patient for surgery with full contact restraints via a bi-lok CNC vise w/ aluminum jaws. You can see the extractor laying on the lower part of the vise:

And this is the type of blast pattern we like

From: http://www.flickr.com/photos/wmode/3354075063/

Happy birthday Samuel Colt!

July 19, 1814.

Now that's some rifling

Sick:



Hat tip: wikipedia http://en.wikipedia.org/wiki/File:105mm_tank_gun_Rifling.jpg

how to break a bull barrel python

I have a bull barrel python that has a big aristocrat rib on it, seemingly setup for PPC.

I thought that this meant it was fine for near max 357 mag loads. Unfortunately I was informed that PPC ribs were in fact designed to keep the front sight on the X ring when doing powder puff 38spl loads and using them for 357 was going to cause problems.

This is unfortunate since I only learned this useful fact after the rib flew off my gun tonight and whacked me on the head when shooting 357. The empirical record suggests that the rib is fairly heavy, in case you were wondering.

Here's how things should look:



And like magic, reality shows how they actually look:

Fixing misfires in a 41 mag python

[As always: this is just for entertainment purposes. If you do any of this t your gun it's going to get ruined! Note there are suggestions at the end of the post for things to do differently.]

I recently got a 41 mag python, which got dissected to see how Jack Huntington did the conversion (http://coltpython.blogspot.com/2009/07/forensic-photos-41-magnum-python-by.html). It had a lot of enshake which I fixed (http://coltpython.blogspot.com/2009/07/fixing-endshake-on-41-magnum-python.html). And while it didn't blow up after shooting a couple hundred rounds (http://coltpython.blogspot.com/2009/07/41-magnum-range-report-it-does-not-blow.html) it would also misfire about 1 round per cylinder.

The misfires were with large pistol CCI primers. I got told to just use federal, but that's cheating, so spent some time this weekend attempting to fix things.

The DA pull is around 6.2lbs, so it's possible that the mainspring is the problem. However, I've done colts that have a lighter pull and they've worked w/o issue, so the problem could be something else. Admittedly these other guns shoot 357, so perhaps the force needed to ignite small pistol primers is less than for large. However, I don't want to just blindly increase the mainspring as a way to mask any underlying issue.

To spare you the dynamic tension, in the end I did wind up increasing the mainspring by about 4oz but a lot of stuff got fixed along the way, so perhaps it's interesting anyway.

Just for reference here's the gun after the endshake fix:


A good colt smith gave a rundown of things to check for tracking down misfires, so we do some of those first.

making a 50bmg barrel.

Not super detailed, but interesting nonetheless: http://www.riflebarrels.com/articles/50calibre/chambering_50cal_rifle_barrels.htm

More Randy Lee on hammer mass and firing pins

http://smith-wessonforum.com/s-w-smithing/90499-my-thoughts-firing-pin-length-ignition.html

I need to track down the rest of his posts. But anyone that gets reliable guns at a DA pull of 3lbs needs to be paid attention to.

Hat tip: Paul D.

WSJ picks of top econ blogs

http://online.wsj.com/article/SB124768581740247061.html

I'm slowly working my way through. Of the first few, this one seems the best: http://www.calculatedriskblog.com/

just got a emco (not enco) compact 5 CNC!

I just got an emco CNC compact 5. The good news is that the thing actually works, despite the cheap price. The bad news is that it's the first generation so doesn't even have a place to plug in a cable to the computer.

"Suboptimal" is a charitable view of this setup.

I can't seem to find a reasonable 3 jaw chuck so had to go with collets instead.

In relief news I was able to figure out most of the 12 simple (g code) commands it provides. The manual I have seems to be for the latter versions, so a bunch of stuff they do does not work on mine. Like deletion.

So now I can make it go back and forth, in circles, and other fairly rudimentary geometric shapes. Nothing that would make Euclid interested, but still.

Useful machining techniques.

Cute trick: stick drill chuck into lathe headstock to make poor man's collet holder. Surprisingly good runout.

http://www.astronomiainumbria.org/advanced_internet_files/meccanica/easyweb.easynet.co.uk/_chrish/techindx.htm

Useful rundown of lathe brands

http://www.cnccookbook.com/CCResourcesBrands.htm

Short Jerry Miculek videos on revolver shooting

http://www.myoutdoortv.com/pdk/web/smith.html?feedPID=00zG15zm84msK0GbWemanhJ0KNWQYqM4

Very useful, though abbreviated.

Finally: unimat 3 is up and running.

Finally, my unumat 3 is running. I didn't know much about them when I bought it on ebay and it turns out it had been completely stripped of all needed parts, other than the motor. Finally got the belts today, so put them on, fussed with some other stuff longer than needed (I have the manual, but it remains unread) and then started cutting.

I got 40lbs of carbide lathe tools very cheap recently, and fortunately a bunch of them seem to more-or-less fit the tool holder.

It's so small I'm not quite sure how to use it for colts, other than making slightly larger than stock rebound pins for guns that have expanded holes.

Here it is making nothing in particular besides brass shavings:

First Etalon!

I'm a bit late to this party, but in any case, my first Etalon arrived today!

I'll be busy measuring the width of different page thicknesses for a while.

Forensic photos: Sherman Roller Action

There's been a bunch of threads on the Walt Sherman "roller action" where he used a ball bearing to reduce friction in double action. Unfortunately there hasn't been much detail. So to fix that we now err on the excessive detail end of things.

I bought a purported Sherman Officer Model Special (OMS) in 38spl a while back with Fishpaw grips, but hadn't had the courage to open it up.

Well that changes now! It was a pretty interesting set of internals that were in the gun.

Outside

Here's the outside:

41 magnum range report: it does not blow up!

Last week I blasted a bunch of ammo through a 41magnum python (conversion by Jack Huntington) and it didn't blow up. A lot of people were skeptical a python could handle 41 mag loads so it was a pretty nerve wracking first few shots.

E.g., here's dfariswheel's recounting of the background of the ill fated 41
magnum attempt by colt (from http://forums.1911forum.com/showthread.php?p=1975991 ):

Colt NEVER cataloged OR SOLD any of them.
They were all pure experimentals that were never sold.

The ONLY genuine factory Pythons ever sold were in .357 Magnum and the Colt
Target Python in .38 Special with an 8" barrel.

Colt did make ONE .256 Python. It fired one shot, locked up, and was never
fired again. It's in the Colt museum.

Colt made about TWO or three .41 Magnum Pythons on request of a large
distributor.
Colt had second thoughts about the safety and took all of them back.
These .41 Mag Pythons are now in the Colt museum.
NONE were ever sold or allowed outside Colt custody.

Colt put a .22LR Python on a catalog cover, but the gun was never made, and
the picture on the cover was an airbrushed artists picture of what it would
have looked like.

There are "Colt Python" .41 Magnum guns around.
These WERE NOT made by Colt. These were made by some custom gunsmith in
Florida??
After customers sold the guns to other people who didn't know they weren't
factory guns, they started shooting them, and they started coming apart.
They returned them to Colt demanding they be repaired.
Colt traced the custom maker down, and he quickly closed up shop and left
town, one step ahead of Colt and customer lawyers.

These fake .41 Magnum Pythons turn up from time to time, ALWAYS with the
inference that they are Genuine Colt Factory Pythons.
They often have the story that Colt won't issue a factory letter on them
because they somehow "Slipped out of the factory".
They aren't Colt, Colt didn't make them and Colt strongly denies they made
them.

There is at least one other fake .41 Magnum Python around, but it's so crudely
made and the markings are so crudely done, no one argues it's a factory gun.

Fact is, the .41 Magnum is simply to powerful for the Colt Medium frame, and
the .44 Special is physically too large.
There just isn't enough metal there to withstand the pressures.



An unanswered question is WHY a gunsmith with the skills and talent to make
the .41 Magnum guns, AND so closely fake genuine factory markings, would make
something he HAD to know wasn't safe.
Sellers or owners of fake .41 Magnum Pythons will dispute the facts and claim
that Colt is lying about them.

Again, while Colt did experiment with several other calibers of Pythons, all
of them are in the Colt museum and the only factory guns ever sold were in
.357 and .38 Special.
Last edited by dfariswheel; 11-15-2008 at 07:53 PM.

Despite the sensible warnings from grown ups, things went smoothly, other than I had some misfire issues in double action that I've still not figured out yet.

Jack stated that you could run 1,000 fps 41 mag loads through it all day and it'd be fine. After shooting around 150 or so (the range was closing so there wasn't time for a serious stress test) his statement seems plausible. The recoil isn't as sharp as near max 357 loads. And the gun seems very consistent. I wasn't aiming worth a damn but it'd pretty much put it where I pointed it: e.g., a 12 shot string all in a 4 inch shoot N C at 15 yards with no fliers. I was using Unique, which doesn't seem to meter well in my dillon so that is saying something.

Before we could shoot we had to make ammo. So here is what we have to work with. 500 new starline cases and two 500 bullet boxes of lasercast 215 gr bullets.

2.5" snub needs a recrown.

The trick I was told to use to figure out if a barrel crown has issues: shoot a bunch of lead bullets and look to see how symmetrical the marks are. Symmetry = good. Not symmetry = not good.

I have a 2.5" snub shoots hard to the left and after checking the marks recrowning seems like a useful thing. I broke down and ordered a frame wrench from brownells. I'll make mine after seeing how people who get paid money do it :).

I'm currently trying to get a near mirror finish on the muzzle of a junk python barrel (bore rusted, heavy pitting, etc). It's taking a bit longer than one could hope for.

Here's the damning evidence --- the previous owner was extremely uncareful (cleaning? Drop? Bang around in safe?):

won a hardinge cataract tool room lathe today!

Price was great. The UK lathe site has an excellent rundown:

http://www.lathes.co.uk/cataract/page5.html

Only 300 or so made. Only 15 or 20 exist. Looks very solid.

Hopefully I can arrange the shipping w/o much hassle. (It was local pickup only but I don't want to drive to LA...)

I'm now debating on a Schaublin to go with it. It turns out there *are* more expensive ways to waste time than buying colts!

Here's some small pictures: looks very clean, with lots of tooling.






And here's a larger photos of a restored one from the fantastic UK website above:

Fixing endshake on 41 magnum python

I got a 41 magnum python conversion a while back, but unfortunately hadn't been able to shoot it b/c of excessive endshake. The difference between the max and min barrel / cylinder gap was well over .005 and, even worse, the minimum barrel / cylinder gap was about .00025 which made it seem likely the cylinder would slam into the barrel.

This weekend I finally got a chance to fix the problem by cutting out the cylinder, machining a bushing and putting it all together (with a bunch of fitting). I first did two shooter model 357s for practice (it won't be an easy matter to replace a jacked up 41 mag python cylinder) and then did the 41 magnum.

The process was not entirely smooth: I had to rip one bushing out and start over and the fitting was made excessively tedious since I did not record the minimum barrel/cylinder gap measurement before cutting out the cylinders. However, in the end all three colts now have < .001 endshake. Of course, they need to survive a bunch of rounds before declaring success. But, that's why god made next week :)

In promising news I've already done the identical fix to two pythons and a trooper when I went out to visit Frank Glenn. For these three colts it seems that things were done right: when I finally did a range test last week they survived 500+ rounds between them without issue. (They seem smoother too since they started at close to .0000 endshake, which forced the cylinder to travel through any binding rather than slip around it.)

OK. So let's get to it. We get excessive endshake when the collar on the cylinder is too short, and thus allows the cylinder to travel forward too far. You can stretch the collar using a special fixture but, unfortunately, that's a one time fix. We instead replace the collar by removing it and putting in a bushing in its place: you remove endshake by making the bushing sufficiently long.

Our algorithm:

1. Measure headspace to make sure we are comfortably above the minimum. If not, we can't do this fix (and likely will have to replace the ratchet).
2. Take the cylinder apart completely.
3. Put the cylinder in a 4 jaw chuck in a lathe and use an indicator to ensure that as it spins it wobbles by less than .0005".
4. Use a boring tool to cut a hole where the collar is until all (or just about all) of the collar material is removed.
5. Construct a bushing that reaches the bottom of the hole and has has a wide enough diameter so we can press fit it in the cylinder. The "collar" sticking out needs to be thinner than this part so it does not contact the barrel.
6. Press fit the bushing in.
7. Slowly remove material from the collar until the cylinder will fit in. Slowly remove more until it will turn. Be careful: just b/c the cylinder isn't turning doesn't mean the bushing is too long! It could be that 0 endshake is exposing other sources of binding.

We'll step through each step.

Cutting collar

Here's the cylinder and the carbide tipped boring tool we're going to use to cut out the collar and make a flat bottomed hole:

Some interesting revolver work

http://www.apextactical.com/

Apex seems to have an excellent reputation and some interesting ideas. E.g., the highly recommended apex barrel has 10 lands and grooves (!?):

http://www.thehighroad.org/showthread.php?p=5703409

Or the use of a lighter cylinder to reduce DA pull and momentum:

http://michaelbane.blogspot.com/2005/09/super-625-45-acp-revolver.html

And here Randy Lee of Apex gives a rundown on the affect of a lighter hammer on DA pull. He's gotten it down to 2lbs 14oz w/ carefully seated federal primers! :

http://www.brianenos.com/forums/index.php?showtopic=26837&hl=randy+hammer

Looks awesome. I'm going to try that out on some bobbed hammers I have.

22 jgr followup

I bought a very interesting officers model special that was converted to 22 jgr a while back. : http://coltpython.blogspot.com/2009/05/forensic-photos-weirdo-22jgr-oms.html

One of the most tricky things was that the gunsmith had modified the OMS from using a hammer mounted firing pin (as all E frames used) to having an internal one, much like the I frames that came after it (python, trooper, m357).

One of the less interesting things about it is that I didn't see a way to reload 22 jgr with any degree of happiness.

On friday however a kind soul mailed me a 22 WMR E frame cylinder so that I could convert the 22 jgr to 22 wmr. That was a major event.

Then I happened to stumble across a discussion about how 22wmr is .224 diameter and 22lr is .222 (or so) so conversions don't work. Since the OMS was converted from 22lr this induced stress: while I can install cylinders, I'm not setup to rebarrel .22lr to .22wmr especially on an essentially irreplacable gun.

But, lo and behold, today we discovered that 22jgr is .224 (as, apparently, most center fire 22's are):

http://members.shaw.ca/cstein0/revolver.htm

So, everything is set for happiness at this point. Other than I have to fit the cylinder, which hopefully won't be a big deal.

Forensic photos: 41 magnum Python by Jack Huntington

I've never seen any dissection of a 41 magnum python, nor really of a professional action job, so let's fix that!

I recently picked up a 41 magnum python conversion done by Jack Huntington (http://www.jrhgunmaker.com/). He was nice enough to chat on the phone. In his view it can handle a steady diet of 1,000 fps 41 mag loads. He also stated he worked at colt for a couple of years and has done around 2000 pythons. He did his version of an action job, including bending the trigger sear.

So, it'll be interesting to see what he did.

Last night I finally got to open stuff up. There were some interesting results, both in terms of what he did and what he didn't do.

Here's the gun (wrong stocks, I know):