Dang, back again already with a Walker question--hand plunger spring

[OD#3]

So I've been correcting some things on a new Uberti Walker, and I decided to push things a little further than I probably should--mostly out of curiosity and also because my hand channel stone broke, leaving me unable to immediately work on that area.  So I decided to tackle a hand spring plunger modification.  The extra real-estate present on a Walker in the area I was going to have to drill boosted my confidence.

Now, I know that the Ruger plunger and spring are recommended, but I believe that is for smaller revolvers.  As this is a Walker, I opted to make my own out of an older worn-out drill bit and the plunger spring from a Browning Hi-power's magazine safety that I'd removed.  Having no real guidelines, this was a fit-and-try affair, but I think I eventually cut too many coils off of the spring.  This thing cocks smooth as silk, but I noticed immediately that the cylinder rotated too easily.  At half-cock, it is just too easy to spin the cylinder; the clicks, while positive, do little to retard the rotation.  There is very little braking action applied by the hand now, and the cylinder is now  susceptible to over-rotating if I don't cock it carefully.  I either need to do it leisurely or fast.  In-between, and I'm liable to induce a brief pause during my cocking stroke--enough to allow the cylinder's stop notch to rotate past the bolt. 

It was only quite recently (and unfortunately AFTER I'd started modifying this Walker) that I stumbled across a discussion on this board about the pro's/con's of hand spring plunger modifications.  Some did it as a matter of course to every single action they acquired.  Others observed that the amount of force exerted on the hand DECREASED as the hand rose, compromising the braking action and threatening over-rotation if one wasn't careful. 

So, anyone else done this modification on a Walker or a Dragoon?  If so, were you able to make the Ruger parts work, or did you have to make your own?  And if so, how much braking action did you end up with?

[OD#3]

Y'know, if I spent more time searching this forum, I wouldn't have to ask dumb questions.  I just found an excellent reply to my query back in November of last year.  But if anyone wants to add or detract, post away.

http://www.cascity.com/forumhall/index.php/topic,58258.0.html

[45 Dragoon]

Nice OD#3!!
  Glad you got it figured out!!  A slight taper profile (top to bottom) will help with the braking effect the new "arrangement" will have on the cylinder. Next, you'll be wanting to go to torsion springs for the bolt and trigger (see my Instagram for a pic.)! That will give you a "break proof"  action for sure!! Works very nice!!

Mike

[OD#3]

You know Mike, the more I peruse your site and your Instagram page, the more I keep asking myself why I didn't just send my Walker straight to you in the first place.  Compared to my time and aggravation, your prices are a real bargain, and I'd be getting stuff done that I can't do/don't yet understand (like the bolt block).  My only benefit from doing it myself is in the education, but I don't know what good it is doing me; it isn't like I'm going to be going into business for myself. 

I could work a couple of extra off-duty assignments and pay for your work while spending my time doing what I know best. 

On a lighter note, I did manage to locate another Hi-power magazine safety plunger spring, and I installed it just a few minutes ago, minus just a few coils.  This works much better and does appear to give a pretty good braking effect.  I've also noticed that the bolt is popping up later than I think it should.  By my estimation, it is hitting just shy of full lockup--much later than I'm used to with single actions, so I may have to take a little off the leg to make it rise earlier, which will also help brake things just a little more.

Incidentally, I'd been wondering about your adjustable wedge set-screw.  I've seen you describe your set screw as 1/4 inch, but since the wedge slot was much narrower than 1/4 inch, I'd just assumed that you meant length--not thickness.  But since perusing your Instagram page, I see that you're actually using a 1/4 inch diameter screw.  How deeply do you drill the hole, and doesn't that compromise the strength a little?  Not a challenge, just a question from an admirer.

[45 Dragoon]

Thanks OD#3!
  Sounds like you figured it out! You won't get the braking effect you would on an Army or Navy, the cylinder on a Walker is a flywheel ( Likewise with a Dragoon)!! Thanks for looking at my Instagram page. The bolt block gives support for the bolt while taking side forces from a rotating cyl. It is fitted to almost zero tolerance and allows the bolt to do what it is supposed to do - which is lock and unlock the cyl. This also helps maintain (along with certain prep. of the bolt head) the lock notches from being battered.

The wedge bearing is in fact a 1/4" set screw with a smooth and polished end as opposed to the cutting cone. The cross section is about right as far the surface it is replacing. The weakest area is the wedge slot in the arbor itself. Since you are forcing (under tension) the end of the arbor against the barrel assy (because of shimming the arbor hole to the arbor), the transfer of forces when shooting allow the two assemblies to act as a single unit.  I recommend flat steel shims (washers) held in place with some JB Weld that has had some steel added ( I collect the metal from my belt sanders/grinders). The added metal will give excellent support without any compression of the epoxy. This setup has proven itself for many hunters using Walkers and Dragoons with maximum charges of Triple 7.  Using split washers (single coil springs) may work with CASS/SASS type loads but full house loads need full house support.  BTW, an action stop works in concert with the "saving your action" program. Drill deep enough to allow threads sufficient for the set screw to enter the wedge slot and contact the wedge. Careful, you can break a drill bit .  .  .   

Mike

[OD#3]

45 Dragoon,
I haven't tried the adjustable wedge screw yet.  I've secured the appropriate drill, tap, and set screw, but it is really going to be a pain to re-bed the arbor hole.  I've been using a metal button (in the fashion of pettifogger's archived posts) who's stem was secured in a smaller hole I'd drilled into the end of the arbor, and that arrangement won't work if a setscrew is in the way of the stem (too bad the stem is too fat for the hex socket of the setscrew).  I believe I'll wait until the wedge starts getting loose.  Then it will actually be worth it to me to go ahead and perform the arbor setscrew mod, and I'll abandon the button in favor of shims in the hole.  As for now, my arrangement is good and tight with a tight barrel/cylinder gap.  I would, however, be interested in exactly how you shim the hole.  You mention shims but then say they're washers, and you glue them together with JB Weld reinforced with metal filings?  Are the washers just stacked in the hole with JB Weld poured into the center of the stack? 

I did, however, perform the action stop mod, and your Instagram pics served as an invaluable tutorial.  Thanks very much for putting those up!  I may try the bolt block one day--again only because your Instagram pics explain it so well.  But I don't compete with this revolver, so I don't know if something like that is worth it or not; I don't cock my revolvers very fast.

On another note, I've learned something about the difference between the round cylinder stop notches on Walkers and the later square cut ones adopted later.  I used to think that the leads in the square notch cuts were just to ease the bolt into the stop more positively.  But that's not all they do, and I discovered this at the cost of the degradation of my action job on this Walker.  I had this Walker cocking smooth as butter.  But it was disconcerting to me how late the bolt popped up.  It was impacting on the leading edge of the stop notch, just a hair before the cylinder achieved full lockup.  This appeared to almost guarantee future cylinder throwby issues as well as causing peening damage to the leading edge of the stop notch.  Today, I shortened the bolt leg until the bolt popped up about as far from the notch as one typically sees with a well-timed SAA.  "Perfect", I thought, until I discovered how much drag that bolt now applied to the cylinder during the final stage of cocking the hammer.  It was only then that I realized that having the bolt pop up onto what is essentially a descending ramp (as it does with the later square cocking notches with the lead cuts), while that ramp is rotating away from the bolt, not only eases the bolt into the notch, but it does so with MUCH less felt drag than one would have without the lead cut.  So my bolt leg shortening, while PERHAPS saving the leading edge of the cylinder notch from peening damage and lessening the danger of cylinder throwby, has ruined the feel of what used to be a very smooth-cocking revolver.  And I'm now thinking that perhaps these Walkers were MEANT to be timed so that the bolt pops up as late as possible.  If I'm wrong, please tell me.  If not....let this be a lesson to the rest of you.   

[45 Dragoon]

OD#3, thanks for the kind words. I hope this makes sense. Your bolt drop may be somewhat saved if you need to lengthen the hand. Does the cylinder lock-up just after the full cock notch is reached (drag a finger on the cylinder while checking timing)? If so, stretching the hand will advance the cylinder some and get you closer to where you want to be. Adding a bolt block will accentuate the "short hand" which will allow even more need to lengthen the hand.  I have to stretch the hand on about 95% of the revolvers I work on because of the bolt block. Now may be a good time to add this little upgrade!!  BTW, the bolt block will protect your cylinder notches as well as protect against throw-by.
  The bolt should drop fully it's width before the locking notch. The tension it exerts shouldn't be more than 3 -  3 1/2 lbs. Of course lock-up and full cock should be simultaneous.

 Good move installing the action stop! It in concert with the bolt block will increase the life of your action parts immensely!! You may not cycle the action very fast now but with these installs, it won't matter!!

As far as the wedge bearing, it gives you the ability to choose how far you want the wedge to protrude from either side of the barrel. A "custom" setting if you will. Different placements may make re-holstering easier. The biggest advantage of the bearing though is the ability to adjust for wear.

Shims. Yes, they are held in place with JB with added metal (like powder,  not shavings). The easiest way is to grease the end of the arbor and let the grease hold on to the first shim then with a dental tool or tooth pick, apply some JB and continue with your stack. After the last shim, add a pretty good amount (you'll learn how much with experience) of JB and carefully install the shim stack into the barrel assy. Drive in the wedge and let it cure. I use 5 min. JB.
   To make it easier to do the shim stack method, install a stack that is a few thousandths thicker than you need. Then, you can dress the end of the arbor down and zero in on exactly the barrel/cylinder clearance you want. Of course, taking material from the end of the arbor opens the wedge slot . This is where the adjustable wedge bearing comes in handy!!

Hope this helps.

Mike

[45 Dragoon]

OD#3,
 A guideline for setting up an action may in order (no pun !!).
The basic steps are:
1. Define the cycle length. Cycle length is from hammer at rest to the full cock notch. Since you have installed an action stop, that will help you get a more exact end of cycle.
2. Achieve simultaneous lockup and full cock engagement by lengthening/shortening hand as needed.
3. Adjust bolt drop.

If you are doing any parts modification (bolt head sculpting, hand dressing, trigger sear clearancing etc)  or adding  a bolt block, do these before you start with the action sequence. Doing these changes/updates later can have ill effects on a previously  tuned action. The more "accurate" you make the action, the longer it will remain in tune, the longer the parts will last, the happier the owner will be!!

Mike

PS, since the "stone" you were using broke, leave it that way and get some files. Files maintain a surface plane, stones change/wear with each stroke. Also, sandpaper on a known flat surface is a most excellent way to dress parts.