Recoil spring replacement.
 

When I ordered the new springs for my Nambu, I also ordered a new recoil spring for the Luger. I put it in tonite, using a hybrid approach of Thor's instructions, a YouTube video I found, and my own improvisation. My addition to the technique was to temporarily insert a spacer at the bottom of the spring to hold the hook up so I could hook it onto the do-dah that it hooks to - as I didn't have gravity assisting me as in Thor's technique. No underbench to work with.

In any event, it was pretty much a piece of cake compared to the thrash I went through replacing the takedown lever spring!

I had wanted to replace the recoil spring before a planned range trip this Sunday - and as I had broken a thumbnail at work today (Horrors! The humanity! :D ), I figured tonite was the nite to get this project out of the way!

Zorba, Congratulations! One of the tougher things to do on a Luger.

I'd rather do a recoil spring than that darn takedown lever spring. Ugh!

both the take lever spring and the recoil spring, well, most of the time they are little devils!

the take down spring, if I can get an edge into the groove, it will just slide in, but yes, I have spent 30 minutes and having it slide out under pressure from my pliers...

the recoil spring is a lot easier with a tool i bought from a forum member, it still can be tricky, but you use a screw driver with a bent and sharpened point and it is easier...

Ed, can you post a pic of that tool??? :)

If not, is it made from a Phillips or flat screwdriver??? How exactly is it used???

Here is the thread: http://forum.lugerforum.com/showthre...in+spring+tool

Here are the photos:
http://forum.lugerforum.com/lfupload...pring_tool.jpg

http://forum.lugerforum.com/lfupload/mvc001f_copy5.jpg

http://forum.lugerforum.com/lfupload...mall_copy1.jpg

Here's the one I made from a spare Torx driver. I offset the tip in order to center the forces more, and clear the frame better. Pretty snazzy, eh?

Thanks for showing/linking! :thumbup:

I've only had to detail strip 2 or 3 Lugers, and frankly I don't recall how I got that mainspring in/out...But I do recall having it facing the wrong way when I was ready to finally 'set the hook'... :p

Now, I'm looking at the tool with the pink background color, and I think the very tip of the tool is split...At least that is my impression...Is it??? :confused:

Edit: I took my grip off to look, and now I remember that I used an old needle-scaler needle (they're 3mm x 7" long and exactly fit in the hole) to use both hands to get the spring compressed, with the frame in a vise.

BTW: I use this tool to pull cuttings off my lathe work, but it should work on Luger mainsprings as well as its primary purpose - Cotter Pin Puller. Should be available at any auto parts/tools store. Handy thing to throw in your toolbox.

I just used a small screwdriver inserted through the hole. One hand to do that, and one hand to place a temporary spacer on the bottom side - hook up the hook, remove spacer. Done.

BUT, did you put it in right-side-up ??
if you didn't, you will have to do it over..............

... :eek: ...

Do you have a picture of the right side up???

I assume you're referring to the hook orientation? If so, the answer to that is "yes". It doesn't look like the pistol would work the other way.

No, I'm pretty sure he means the tight coils on one end and the loose coils on the other...But which end goes up??? :eek:

This could be disastrous!!! The wrong end up and the pistol won't cycle fast enough to eject the fired cases!!! It'll be too slow!!! And if the other end is at the wrong position, it'll cycle too fast and you'll get stovepipes!!! :crying:

Someone, PLEASE post a picture of the correct orientation of the coils!!! :thumbup:

Zorba - The Nambu recoil springs go with the 'loose' end toward the front. You want the spring to compress fairly rapidly until it reaches full compression, when it rebounds. Pic below.

The Luger spring looked equidistant between the coils to me - but I'm not seeing a picture of the Nambu springs, although I A) Didn't know that, and B) Its pretty obvious from your description - provided that I can see a difference!

ETA: Now I see the picture, I don't have gigabit at home...

ETA2: I'll have to examine my Nambu springs next time I disassemble, I don't recall them looking like your picture at all. But my old brain is starting to miss all kinds of stuff - fortunately, the Nambu isn't going to the range with my wife and I this weekend anyway. If my springs are something like that, they'll either both be backwards, or there'll be one each way!

Danger, Will Robinson!!! Danger!!! :eek:

Here's the rule of thumb - Put the tight coils at the fixed end of the spring. On the Nambu, that'd be the back end, where they sit against the frame, and the slide pushes against the front. On the Luger, I think the tight coils go up, because that's where the spring abuts the frame, and the long hooked piece with the triangle at the bottom pushes up... :thumbup:

I just went and had a look at the old spring from the Luger. No discernible difference in coil density from end to end - and I don't recall a difference on the new spring either.

ETA: Take a look at Thor's article on Luger mainspring replacement. My spring looks just like the one pictured there - no difference. Nor does he mention one. I think we're getting our legs pulled...

I also looked at the old Nambu springs - and can say the exact same thing about the springs. Perhaps not all makers make them like your picture? I'll pull the Nambu back apart when I'm cleaning guns anyway, and have a look, but I'm pretty sure there's no difference there either...

<Whew!> You're OK then. Non-progressive springs can be installed either way. :thumbup:

I was going to explain left-hand twist springs vs right-hand twist...But that can wait until another time. ;)

Is that sorta like a left handed Crescent wrench? :roflmao:

Ah, no...And you can't hunt snipes with it either...

You can wind a spring in either direction, to the left or to the right...In a system where you want two balanced forces working in harmony you would have one of each...In production pistols, rifles, motorcycles, etc this is impractical, but in high end systems you would spare no expense...You'd use ground wire, not drawn; and the ends would be ground flat and parallel...The number of coils would be equal and the overall length would be equal also...

When I worked as a millwright we often made our own springs (obsolete equipment)...Spring Winder pic attached...You feed the wire in and turn the crank...There is a finger that is adjustable for distance between coils, the mandrel determines diameter, and wire diameter determines resistance to deflection...

http://ecx.images-amazon.com/images/...500_AA300_.jpg

As all this applies to handguns, only the high end models have matched spring sets...But you can buy them for specific handguns... :thumbup:

This could be employed on a Nambu, but not on a Luger - yes?