Uberti timing

Holsterguy · December 03, 2017, 04:51:23 AM

Ok, got a question for all you sixgun slicker-uppers. Got a new Uberti with the retractable firing pin. Couldn't handle the fact it was missin a click, and got a new plain hammer and trigger. Installed them, and now the bolt pops up just a little late. ( at the end of the lead notch instead of the beginning) Where do I have to stone the bolt? Is it the length of the leg is a hair too long?
Thanks in advance!

45 Dragoon · December 03, 2017, 08:45:25 AM

To answer your question, yes. The length of the left bolt arm needs adjusting . . . but, it may be correct!
First thing to do is check bolt spring tension as most of the time it is excessive. Too much tension will mask other problems and cause premature wear/failure. The bolt head should exert about 3 lbs of pressure against the cylinder (or your finger!) You can adjust this by slightly re-contouring/ thinning the bolt spring.

Now, make sure cyl lock-up and full cock notch/sear engagement occur simultaneously. These two events are your 4th click. Check it by dragging a finger on the cyl while slowly cycling the action. If cyl lock-up happens just before the full cock notch is reached, the hand length needs adjusting (shorter). If this is the case, correcting the hand will probably retard the cyl carry-up (rotation) to correct the bolt drop timing. If lock-up happens after full cock is reached, the hand needs to be lengthened (stretched). In this case, you'll need to remove even more arm material since bolt drop will be even later.

If cyl lock-up and full cock check out OK, then the left arm of the bolt needs to be shortened. Where do you remove material from? Two ways to go here. Check the position of the bolt at 1/2 cock. If it is well below the frame surface (water table ) you should remove material from the very rear most vertical surface. This is how you adjust the amount of bolt withdrawal. Excessive withdrawal puts too much un-needed force/movement on the bolt spring causing early failure. By removing material here, you are adjusting withdrawal and drop simultaneously.

If the bolt withdrawal is OK (at or just below the frame water table), then remove material from the horizontal (top) surface of the arm. This will adjust the drop and only the drop.

Sorry for the long explanation but the bolt is the most complicated action part to fit.

If you are going to install a bolt block, do so before you do any adjustments. The movement will be consistent and precise but it will affect the timing .

Mike

Holsterguy · December 03, 2017, 12:21:48 PM

Thanks a lot Mike. Yes, it does sound complicated.

RRio · March 30, 2019, 03:26:35 AM

Quote from: Holsterguy on December 03, 2017, 04:51:23 AM
Is it the length of the leg is a hair too long?

Yes. Take just a little off the back leg that rides over the cam that is on the hammer. I just bought a new Taylor with the RFP and it slicked out really well. I have been doing action jobs on these since 1978, so I was honestly surprised.

Bibbyman · March 30, 2019, 07:47:30 AM

Here is an example of my Pietta Eleminator where I'm testing cylinder rotation and timing at full cock notch. The second step on the hand is too short and cylinder is no where near locking up.

I stretched it some and about have it close to where it needs to be.

RRio · March 30, 2019, 08:58:09 PM

Quote from: Bibbyman on March 30, 2019, 07:47:30 AM

I stretched it some and about have it close to where it needs to be.

What did you use to stretch it with?

Bibbyman · March 31, 2019, 02:03:56 AM

Quote from: RRio on March 30, 2019, 08:58:09 PM
What did you use to stretch it with?

I used a high tech device only obtainable after going through training and certification by a government review board.

I tinkered with it yesterday and got it to this point. The hand is shockingly soft. I'm thinking I should harden it.

RRio · March 31, 2019, 02:27:05 AM

Oh, I see. The ol' ball bearing makes the hole smaller trick. I've got an old hand or two i will have to try that on. Thanks.

Bibbyman · March 31, 2019, 04:55:31 AM

I do all kinds of goofy things almost daily. I've started making DIY videos and uploaded them to YouTube. I'm in the process of editing a video now - splicing clips included here and pictures and narrative.

If I were to do this again, I think instead of a drill shank, I'd either make a rounded punch or use the edge of a combination wrench with about the same radius. One problem I had was accidentally bumping the "post" on the hand and dinting the edge that I had to hone off. Something taller would have saved me from this accident.

This is not a method of my invention. I found references to the procedure in AGI course and other places - including consulting friends knowledgeable in gun repair.

willy · April 07, 2019, 07:20:55 PM

Quote from: Bibbyman on March 31, 2019, 02:03:56 AM
I used a high tech device only obtainable after going through training and certification by a government review board.

I tinkered with it yesterday and got it to this point. The hand is shockingly soft. I'm thinking I should harden it.

Great tip...I used a punch to stretch a hand before and it didn't really work all that well..But your way seems the way to go....Who said you can't teach an old dog new tricks?

RRio · April 07, 2019, 09:02:50 PM

Quote from: Bibbyman on March 31, 2019, 02:03:56 AM
I used a high tech device only obtainable after going through training and certification by a government review board.

Oh, I see. You used a molecular displacement tool ! Very good!

Bibbyman · April 08, 2019, 11:57:01 AM

Here is a longer version of the how to video. Again, I didn't invent this method of stretching the hand. I just found out about it. It worked well in this case because the Pietta hand was soft. If you run into a hard one it may shatter.

Additional notes; Making the dints extrudes metel out onto the front and back sides that must be removed. I just struck them down with a fine file and polished. By the time I had beat it enough to get it long enough, it had a slight bend. I turned it over and hit it with the hammer to straighten it.

Abilene · April 08, 2019, 01:05:33 PM

I only tried to stretch a hand once (used the method shown above, which I also got from an AGI video). I think it was an Uberti hand. I hit it hard with the hammer on the drill shank, and never made the slightest dent.

45 Dragoon · April 08, 2019, 01:09:52 PM

It'll be best to remove the spring and heat it red hot and then stretch it (both sides. Not sure why you wouldn't . . .).
Since it's hot, it'll be soft and will stretch easier and you won't break a hard hand. When you've checked for correct length or slightly long, you can re-harden and re-install the spring and fit accordingly.
I have to stretch 90+% of the hands in my customers revolvers (because of narrowed tollerances) which just goes to show you how much slop there is in a "well timed" revolver! Lol!!

Mike

Coffinmaker · April 09, 2019, 09:11:18 AM

Hardee Har Har

So true Mike.

45 Dragoon · April 09, 2019, 09:59:44 AM

Thank you Mr.Coffinmaker!

RUSS123 · December 28, 2019, 06:08:42 PM

If I may ask. New to this forum.

What is a bolt block and what is its function? Thanks in advance.

Russ

45 Dragoon · December 28, 2019, 06:54:58 PM

Russ,
A bolt block is a "chunk" (filler) of metal that lays beside the bolt and takes up excess space between the bolt and the wall of the frame. It is a close tolerance fit but allows easy movement of the bolt vertically but "none to insignificant " laterally. It gives support to the bolt when the rotational force from a screaming cylinder comes to a sudden stop. It provides a very solid lockup, protects the locking notches and is a big factor in preventing cylinder throw-by (over rotation). As simple as it is, very few folks take time to install them. I install them on every S.A. I work on.

Mike

RUSS123 · December 29, 2019, 03:15:13 PM

Thanks Mike, makes sense. I guess this is something you make yourself? I've never seen anything sold by that description. I don't do any cowboy shooting. I'm just an admirer and a range shooter. I am aware of of the potential stress the bolt is under. I cock mine softly because of that awareness. Just saying. However, I love to know these things. I own 3 Ruger SAs, 1 Pietta Frontier and 1 Uberti 1872 Open Top which I just bought from Cimerron last week. I've got questions but I'll present them separately in a new thread. You sound like a smith. Thanks again.

Russ

45 Dragoon · December 29, 2019, 04:36:01 PM

Russ123,
Well, I don't call myself a "Smith" I'm a tuner. Even though I correct "what needs fixin' to make it right", I'm a tuner. It's the way I was taught . . . you are welcome to visit my website and Instagram feed to see " what's up".

Yes, I make each one for the revolver it is going in . . . "it's custom" !!!! Same with the coil springs and action stops and . . . you get the picture . . . The main thing is that I'm very anal !!!! Very . . . (to a fault !!!)

Eddie Janis (of Peacemaker Specialist) used to offer it but I don't even see it on his site anymore . . . he was one of VERY few that even offered it!! I always install one along with an action stop! These two items are (to me) extremely important for longevity and reliability!! . . . Whatever . . . with these , you don't need to worry about "cocking softly" you can "let'er Rip !!!

Mike