Wednesday, January 30, 2008


Well, it seems the gun blog has become the gun and electronics blog... and that's ok.

MSL is now completely in the basement though I still need to arrange everything and hook up all the equipment. There's a fair bit more storage space there but there's also a lot more junk and I've got the feeling I need to sit down, bite the bullet, and fill up a 40 gallon trash bag or two. I've always had a touch of the packrat gene...

There's new stuff on the way, in both camps. There's another box of tubes coming, a 29-count lot. I *wanted* one tube, a 1S4, but for $30 I got a whole box of 1-5v low voltage tubes that are going to be much easier to play with than the six to forty some odd volt stuff from the other lots. A D cell for A supply and ten or twelve cheap rechargable nine volts (8.4v X 12 series = 100.8v) for a B supply and I'm good to go there. I have in my hot little hands a schematic for the 1S4 that makes a nifty single ended ~150mW audio amp; it's partially transistor based since it uses a hex schott trigger and a 2n2222 as a "tickler" for an inductive circuit that raises 3V to ~100 for the high tension section, essentially a crude "switching" power supply. Schematic calls for AA cells but I'll use C or D cells for time, and it also says Hammond 1650P... no way am I shoving a $75 transformer onto what's basically an overwarmed headphone amp. I'll find some cheapo little ~7K/8ohm transformer to use instead.

I have a feeling that the "chassis" I'm going to use will be improvised, and that main input will be a 1/4" mono jack... a little nifty practice amp for guitar, which I still want to learn how to play eventually. If I can make the cells fit it might get built into an upside-down aluminum backpacker's mess kit.

I did mention there's stuff coming as far as gun items... I found a cheap copy of Datig's Cartridges for Collectors, Vol I on Amazon yesterday.

To close with a strange gun, the shop has a stainless Bauer .25acp. I have an Italian pocket mouse gun, I have a French pocket mouse gun. Shall I have an American pocket mouse gun? I await pricing. I'll also have to get rid of the shnazzy second-cousin-of-pearl grips, if I can. The gun is basically a stainless Vest Pocket copy, pretty well made at that.

Saturday, January 26, 2008

By the way...

... I haven't given up on the radio project. I was sick for nearly the entire first half of January, and now I'm of a mindset where I'm moving the entire MSL to the basement so I can use this room as a bedroom again.

Ah well.

Walther P5

(I do not own this gun. This is at the gun shop, price not yet set.Photos taken with the ancient 1.3MP Olympus, click for larger image)

This is quite an unusual weapon; designed in the late 70's, this was Walther's first foray away from the P38 style of handgun as duty weapon. It's full of strange design features and still has a little bit of P38 lineage in it. Click on each image to enlarge.

First, just a side shot.

Upon opening the slide, you can immediately tell that this isn't a browning-style lockup, the barrel stays linear to it's axis. I'll get to this.

The pistol has the classic European style magazine release on the butt behind the mag well.

One of the most unique features here is the articulated firing pin. Instead of a blocking style firing pin safety like you'd find on everything else, with the trigger at rest the firing pin is in a low position where the end finds a blind hole in the hammer and would not be struck if the hammer fell. When the trigger is pulled, the firing pin is pushed up where the hammer can strike it.

The takedown lever is at the front and simply unblocks the barrel assembly.

Here you see a little of the P38; the barrel is locked with a block, actuated by a pin that presses against the frame during recoil.

Barrel removed (inverted), locking block in the "unlock" position

And the last of the oddities, here are the dual small diameter recoil springs. This was probably done in the interests of keeping the pistol compact, avoiding the placement of the spring underneath the barrel of behind the grips (Beretta tip-up style).

The pistol has a very nice trigger and is probably very accurate, though I can't verify since it's not mine as its' for sale at the shop (price as yet unknown). Another little odd feature of the pistol is that the lever on the side is dual purpose (see photo #1). With the slide locked back, the first downward sweep on the lever will drop the slide forward. A second sweep will decock the pistol. If you need to lock the slide back with a loaded or removed magazine, you have to press upward on the upwardly-curved piece of metal on the frame ahead of the main operating lever.

So there you have it; the Walther P5 in a nutshell. Very strange gun :)

Saturday, January 19, 2008


This is regarding the "Bond 1" show and the magnetic watch experiments, towards the end where they were attempting to duplicate the effects at any cost.

Point of error:

- The vast preponderance of .45acp ammo is made of copper jacketed lead. No magnet is going to attract or repel that on a linear basis.

They did however get a deviance from flight path using extremely strong rare earth magnets... but not for the reasons they proposed.

-Bullets spin for stabilization, 1 turn in 16". That doesn't seem a lot, but it's enough over a couple feet of magnets to induce a circular eddy current in the bullet, stopping the spin and introducing a gyroscopic instability because of the higher angular velocity of the rear surface of the bullet.
-Linear eddy currents can have some effect but the bullet does not fly close enough to the magnets for this to be a serious effect. See foucault braking.
-The material of the bullet would not have been directly affected by the magnet at all, it's non-ferromagnetic.

The only reason their bullet was affected at all was because it was moving, and sheathed in a conductive material. I'm inclined to hypothesize that a pure lead bullet, lead being a very poor conductor, would not be affected to a discernable degree.

I could also theorize that if you shot a light weight solid silver bullet in a fast-twist barrel through a strong enough magnetic field that joule heating would cause it to explode, but that's taking things a bit far :)

Monday, January 14, 2008

Rare meme

Go play. :)


Here's another, just because :) I'd forgotten what fun it is to screw around in photoshop...

Thursday, January 10, 2008

Sonata in two parts

Part one: Strange guns

Apologies for the image quality, that's the 1.3mp camera with me using a piece of paper as a background in the back office of the store. That, from the best I can tell or find, is a Driesen or other Liege, Belgium manufacturer's offering in .30 Belgian BP centerfire. Quite neat. It's missing some important parts though, and it's doubtful it could ever be made safe to fire (much less finding an ancient heeled .30 caliber to fire in it). The shop has it "for parts", meaning it's liable to be a curiosity that sits around forever, particularly since it's not a firearm (pre-1900).

Part two: Strange compulsions

With the much appreciated assistance of Roberta X I've been tweaking and fiddling with the old radio and finding that this is an incredibly steep learning curve. So, I'm just going to sit back and remind myself what the plans of attack are:

Plan A: restore full function with new parts (current)
Plan B: restore AM function with vintage layout
Plan C: restore AM function with new layout, i.e. total rewiring
Plan D: restore preamp/amp function, use external audio source
Plan 9 from outer space: Convert dial to clock, hide head unit with amp in cabinet somewhere, shame myself and wear cirice and hairshirt for a couple decades for failing.

Now, before anyone freaks out about the big alphabet plans, I remind you that I do have two chassis for the one cabinet... if I screw up too badly with the first one there's a reprieve. The second chassis is in worse physical shape but seems to be a little less unfocused as to the wiring.

It's rapidly becoming clear that the physical restoration is the EASY part. At least I haven't electrocuted myself again. (that does imply that there was a once...)

Sunday, January 06, 2008

This is the radio post...

I'm making a placeholder and opening up comments without moderation for talk about the radio. Status as of today:

- I've re-verified that the transformer is hooked up correctly and I was just having a massive brain fart as far as how a full-wave rectifier is hooked up.

- there is a circuit in place to replace a 1K ohm field coil, that is two 500 ohm wirewounds sandwiching a 47mfd electrolytic, which is polar, and oriented correctly.

- I replaced a big ole' classic 16 mfd reservoir cap with a less big modern 16mfd cap I got from antique tube and radio. This is the cap that seems to "lose" about 436 volts across it. I can't verify that it's what it's supposed to be in the schematic either, Fairbanks morse didn't see fit to actually put specs on, well, ANYTHING.

- HT voltage out of the power supply circuit is currently running 465 volts DC. Spec, as looking at the sheets' refence for the plate voltages around the unit, is supposed to be 245v. I think I may have an open component yet, as there's still some vintage left, and that may be allowing the power supply to drift high. Way high.

Pictures forthcoming if they help.

Friday, January 04, 2008


The glimmer of the rainbow cast in the sky was nearly as exhilarating as ducking under the spray to reach my water main shutoff valve.

Insulate those bibs, folks, especially the galvanized ones that are sitting lonely in the front yard right next to the water valve. If I ever find out who was responsible for even half the lousy jobs done around this house in the last 55 years...

Wednesday, January 02, 2008

Consideration, further...

I'm looking at the photos I took yesterday on a different screen... and something is obvious.

100W doesn't cut it.

I'll soon be investing in a couple of high-wattage halogen work lamps (the cheapest option) with something to use as a sheet diffuser.

See, I *know* my lighting sucks, but I've been ill-prepared to actually do anything about it :)

Tuesday, January 01, 2008

Happy new year!

Gun Photos!

Click here for photo page.


S&W 66
Para Ordnance 16-40 (10mm conversion)
Nagant revolver
...and one "restored" dagger, stainless/zinc. It had a really lousy plastic coating when I got it years ago...