Problem with Uberti Cattleman

[will52100]

I've got a Uberti Cattleman in 45 colt.  It has always had a hair trigger, I stoned the trigger matting surface, it realy was porly done, and it improved it a good bit.  However recently I had several failure to fires due to the funky safty notch on the hammer catching the trigger sear.  I haven't tourn it down yet to see the problem, am am thinking of buying a new hammer, without the safty, and trigger.  What happens is I pull the trigger and because the pull is light it doesn't clear the safty notch completely and causes a light strike.  When I jerk the trigger to the rear it'll fire everytime.

What'll ya'll think?  I'll tear it down in the morring and mike the pins and such to see which one I got, old model or new and go from there.  Never did like the safety feature.  If I want to cary six I put the firing pin down between case rims and that locks the cylinder, safer to me than a funky hammer notch before halfcock.

Thanks

[will52100]

Got it fixed.  Finaly figured out that by putting the hammer on the outside of the frame and using the pivot screw threw the frame and trigger threw the frame I had a ready made jig to see the hammer sear relationship.  I had though of making one to check hammer/trigger alignment, but this works even better as no two guns are going to be exactly alike.  Ever since new this gun has had a trigger pull problem.  The trigger sear surface was rough and pitted, and out of alignment with the notch on the hammer.  A little filling and checking and stoning and it's at a very slight negative angle.  Breaks clean at just under 3lbs.  Turns out the reason for the light strikes was that the trigger was slipping off the hammer sear and falling back into the hammer safty notch.  If I have any more trouble with it it'll be because of soft mettal and I'll replace the hammer with retro one without the safty notch gimic.

[Driftwood Johnson]

Howdy

The problem you describe is typical of a hammer that has had the shelf of the full cock notch shortened in order to achieve a light trigger pull. I discovered this myself on my first adventure in gunsmithing on my Dad's old Winchester Model '06 when I was about 16 years old.

When you pull the trigger on any gun like a SAA, as you pull the trigger back, the sear (the topmost tip of the trigger), slides forward out of the full cock notch. As soon as the sear clears the notch, the hammer begins to rotate. The geometry of the hammer is such that the overhanging lips of the half cock notch and the 'safety cock' notches can rotate past the release postion of the sear without any interference. However, if the full cock notch has been shortened, the sear no longer travels as far to release the hammer, and so the over hanging lips can contact the sear as they rotate past. In extreme cases, the sear, or the overhanging lips themselves can break off from the continued abuse.

When I bought my Uberti 1873 rifle I bought it used. It had a very light trigger pull. Eventually I noticed it was getting unsafe, the hammer would fall if I simply worked the action. When I took it apart, I found the previous owner had down a butcher job of a trigger job to it, simply filing down the shelf of the half cock notch to shorten it. Eventually the over hanging lip of the 'safety cock' notch broke clean off, from continally being struck as it rotated past the sear. I wound up replacing both the hammer and the trigger with factory new ones.

You mention that you have put a slight negative angle on your sear/full cock notch engagement. If I understand you correctly, that is a dangerous situation and you should replace the hammer and trigger. A negative angle means there is nothing but spring pressure keeping the sear in the hammer notch, and indeed the hammer is trying to wedge the sear out of position as the hammer spring exerts pressure against the sear. The only thing holding the sear in place is the trigger spring and friction. The proper angle is about a 3 degree positive angle. A positive angle means the trigger actually forces the hammer back ever so slightly as the trigger is pulled. That is the proper relationship for the angle. In that case, even with no trigger spring at all the sear is securely wedged to the rear of the notch.

You also may have filed through the case hardening on the parts. Uberti uses pretty soft steel and if you filed through the hardened few thousandths of the skin, wear will accellerate as the soft inner steel of the parts rub against each other.

Personally, I don't work on trigger sear/hammer full cock notch engagements at all any more. I am lucky enough to have the services of an excellent gunsmith who does this work at a reasonable price. If I was going to do any dressing of notches and sears myself I would buy the proper fixtures and stones from Brownells to do it with. I would not touch the surfaces with a file. It is too easy to damage the delicate engagement of the hammer and sear with a few quick strokes of a file.

You might consider replacing the hammer and trigger. You also might consider investing in Kuhnhausen's Shop Manual for the SAA. It is an encyclopedia and will explain all of this stuff in great detail, much better than any other book on the market.

[will52100]

I guess I should have said positive, meaning that the angle is such that the hammer has to be lifted ever so slightly.  I finaly got a trigger pull gage in and boy what a suprise.  All my guns measured between 1 1/2 - 2 1/2 lbs.  The cattleman measured a clean 1.5 lbs.  I actualy didn't take much off the hammer, only stoned it a bit, the majority I did to the trigger.  I should have sent it back when new, but didn't.  Out of the box the trigger surface looked pitted, like it hadn't been cleaned up after manufacture.  The trigger pull got so lite not long after purchase that I had to do something, I'd guess that it was well under a pound pull.  We'll see how the hammer holds up, worst case I'll get a new one, then again I've got the stuff to case harden it so I may go that rout if it wears too quikly.