Saturday, October 29, 2011

RWS (Diana) Model 45 Notes.

Just a few notes about putting the rifle back together.
I polished that rusty washer. Reassembly was largely the same as disassembly in reverse except as shown below. I lightly lubed everything and smeared a little silicone oil into the leather piston seal to get it to swell a little.

First try at reassembly. Ok, this was maybe the fifth time as I had longer pins, had a pin in the other slot, etc. in various permutations.

A slave pin is inserted in the springy part of the safety. This keeps it spread open so I can push the retaining pins through.

Back together with one pin in place.

But the slave pin was impossible to align with the hole. So I looked at the exploded view some more and figured that maybe I had the spring clip upside down – so I put it together as shown. At some point before this I did manage to get it together but the safety was stuck and wouldn’t move.

I also put the slave pin in the forward detent position (which would be “fire” rather than the rear detent position (“safe”).

10281105Punching out the slave pin with the retention pin. Yay. I probably re- and dis-assembled it 20 times figuring this out.

A short slave pin for the trigger – the pin that holds it to the stock has to pass through and this helps.

The pin in place.

Note that the plastic caps for the pins are different on the Original 45 I showed earlier on the blog. These are countersunk with the flange outside. The caps on the RWS have the flange side in. I have no idea why.

The rifle together I turned my attention to the scope mount.

Pushing off the dovetail clamp.

A broken screw, a spring and lots of dried lacquer.

The pieces.

I was able to unscrew the screw holding it with pliers. Finally something easy.

Some new clamp screws fitted.

I punched the location of the scope stop screws. The setscrews are pointy (dog point). So I figured I’d replace them with cup point screws.

Made the punch mark slightly larger.

Spot drilled.

I then drilled shallow holes the diameter of the setscrews. They should sit in the holes and not move. The dog point screws did nothing to keep the scope mount from shifting. You can see evidence of screw marks on the rear of the scope rail.


All done. I shot a little and the velocity is the same (about 730fps) as it was before. So no improvement. I could probably soup it up by replacing the spring or fitting a synthetic seal but why bother? It’s peppy enough. I am wondering if I should have replaced the breech seal though. Maybe soon.

Friday, October 28, 2011

Quick October Update

Just a quick blurb.  Haven't been posting as often lately. As of late, it's mostly due to the weather is changing and any free time has been spent getting the home and yard ready for winter.

I'm stuck on the IZH 53M for a couple more days.  I didn't have a large enough diameter piece of rod on hand to make a new end cap.  Put together a metal order and got some of 12L14 steel in the required size.  12L14 is a "free machining" steel that's easier to work (than a hardenable tool steel) due to it's lower carbon content.  Hopefully, the metal order will arrive later today and I can finish up the IZH over the weekend.

Also have an easy project for my Aeron target pistols on the bench right now.  Want to make a couple metal thread covers for the bulk-fill caps--except  I didn't have a M18 x 2mm tap on hand.  Yep, those are in transit right now, too--apparently on the slow boat as the tracking number hasn't shown forward progress in a week.

So, I'm just stuck in a holding pattern for a couple days.
On another front, I've got some machinery being delivered in the next week that will allow for some projects I've been unable to attempt. 

Keep us in mind if you have some older (new is good, too!) airguns laying around that need a good home.  Non-functional is just dandy as that's the theme of the blog.  We're always looking for project guns.  Sometimes broken guns are useful to us for barrels, sights, valves, etc. If you have anything of value to us--dubious or otherwise--drop us an email or leave a comment and Nick or I will get back to you. 

Sunday, October 23, 2011

Overhauling the IZH 53M Part 1

Got a great deal on this from fellow airgunner Jason B.  It's a like-new IZH Baikal 53M.  Shot it a few times and could tell the gun was a bit dry inside from the factory.  Figured I'd take a look inside and see how it works.

This is at least the second version of the pistol.  The original had a funky, sort of, uh, match-type grip.  It's not much of a reach to assume that the original grip wasn't left hand friendly so it was changed to this design.

Of course, I'd like to have the original grip frame, match gun weirdo that I am.  It's a relatively large pistol as you can see from the 12" ruler.

Diving right in...  Removed the two stock screws at the front.

There's a third screw underneath at the rear of the trigger guard.  They're all phillips head screws.  I didn't actually measure one, but it's a safe bet that they're all M4 x 0.7mm thread.

There's an adjustment screw at the front bottom of the trigger assembly.  I didn't see a hole in the grip to reach the screw.  Maybe I missed it?  Well, thirty seconds of web research shows a hole in the original grip design.  Looks like it was omitted from version two.  So, just take the action out of the stock to adjust the trigger.

Wanted to remove the rear sight next, but the lip on the end cap blocked the rear of the dovetail slots preventing removal.  Looking at the mainspring's wire gauge told me I could do without a serious  mainspring compressor.  I snugged it into a large bar clamp and put some pressure against the cap.

Figured I'd tap out the pin, but it simply fell out when the spring tension was relaxed.  Click the pic to enlarge--note the end of the mainspring--it's buckled against the end cap. 

That was easy. 

The cap is plastic.  Some type of nylon like the grip.

Notice the lack of a spring guide.  The inside of the end cap seems like it was designed to accept a press fit guide.  Back to the web for thirty more seconds of research.  There's no guide on the schematic--not even on version one.  Must've nixed the guide as a cost cutter after making the mold for the end cap.

Wave to the spring.   About now, I'm thinking the lack of a guide isn't such a great idea, and the lack of grease almost went unnoticed. 

At least I can take the rear sight off now.  The foremost screw on the sight unit fixes it to the dovetail.

Piston is still in the gun.  The end of the cocking lever is holding it in place.  Note the ratchet.  It's for the anti-beartrap.  Removed the coil spring for the anti-beartrap.

The end of the cocking lever is just visible in the piston body.

I noticed the side hole in the trigger unit and assumed it's for access to allow removal of the rear link from the cocking lever.  Drove the pin out.  It must be removed from left to right.  Still can't remove the link or the piston.

Drove out the pivot pin for the sear.

With the pin out, the sear is removed, followed by the rear link.

I like how the sear functions as part of the anti-beartrap assembly.  Clever.

Piston.  Looks like the seal is the same as the Model 60/61 rifles.

Here's that trigger adjustment screw.  The trigger had a very, very long, light pull.  The adjustment screw was backed out all the way.  The housing was also bent about 15 degrees from center, so much that the screw wouldn't contact the trigger correctly.

I'll realign the trigger housing so it functions properly.  Screwing it inward will then shorten the travel of the trigger.

More soon.