Hammer & Trigger Swap?

did the hammer and trigger assembly come as a unit? Hammers and triggers are parts that are recommended to be fitted to each other. Not sure how much fitting would be needed if they did not come from the same gp100. The gp100 has also been around for a while so there might be some variations. But in theory it should work if the donor unit came as a set and was not modified. As usual, caution and liability issues can apply.

Did some light stoning on the sides of my hammer btw as it dragged a bit but have stayed away from trigger unit disassembly as the gp100 is not that user friendly in that area. Mixing and matching parts there might cause some issues unless properly fitted.

They really need to be fitted together. One small dimensional change can affect three or four other parts. Unfortunately a revolver is nothing like an AR.

Register at the ruger forum and then you should be able to access their gunsmith section. The issue is that gp100 revolvers have been made for over 30 years under differing mfg techniques which introduces variance. The other complication is rugers use a unit type trigger group which makes it a bit more complicated to work on than a Smith design. Jerry kuhnhausen did write a shop manual for the ruger double actions and I believe that it is still in print. His stuff is pretty good guide and he won't have you doing something unsafe when fitting.

Let's not make that more complicated than it is - just swap the hammer and the trigger group as unit to your 3" GP ant test the action. That should take you about 10 minutes at max! It will either work, or it will not. It's not a hand-fit action like Colt Python, why so much worries...

Mizar,
Not sure from the O/P description that he has the alternate trigger parts as a unit or as individual pieces.

O/P, if the trigger unit is intact from the 6 inch, then use the matching set as Mizar mentions, otherwise, be careful.

GP-100's have been made for a while and there is some differences in manufacturing processes over time. Could result in a horrible trigger or an unsafe one if not properly fitted.

Poper,
One thing you can do if you want is use Brownells trigger magic or sentry solutions has something similar to slick up the trigger. Wilson Combat or Wolff also make a set of springs where you can tailor your trigger pull for pretty cheap (under $20). The DAO hammer spring is probably the oem factory spring. Expect a bit longer locktime and perhaps a bit heavier trigger as it will be moving a heavier hammer with the spur and all.

What a minute. You just want to change a spring(post#9)?

Changing the spring under the hammer has almost no effect upon the trigger pull weight. That is a function of the angles and finish of the sear and hammer hooks. If those angles are off changing springs isn't going to help. Changing the trigger return spring will make a small difference in DA only. The DA sear must have exactly the right length or the trigger will stutter in DA. The same thing applies to the hammer dog. A few thous. variation will hang up the trigger in DA. In SA it's all about the sear and hammer hook angles. All of these parts must be carefully fitted together into one frame for positive function. If you want a nice trigger then let a qualified pistolsmith do the work. Dropping in parts from another gun is not the way to do it. What you can do and see benefits in DA only is to carefully remove all of the burrs that Ruger leaves inside every gun they build. And they leave A LOT of burrs in the frame. That is where most of the friction you are feeling in the trigger come from.

https://www.youtube.com/results?q=ruger+gp100+full+disassembly
Link to dozens of YouTube videos dealing with GP100 disassembly.
On Rugers the trigger group, consisting of trigger, hand, bolt and transfer bar, is a removable unit. That is why I suggested you to just swap them and test the action. You should expect that the hand may cause timing problems, because it's a part that needs fitting, but for start trigger group & hammer swap is enough to tell you if more thorough parts fitment is needed.
Follow this link to revolver action testing: https://www.thehighroad.org/index.p...r-checkout-10-year-anniversary-update.695644/
Just do it with cylinder removed, or swung out, so the new hand is out of the equation.

Best,
Boris

Mizar said:

On Rugers the trigger group, consisting of trigger, hand, bolt and transfer bar, is a removable unit.

Click to expand...

But the trigger is not part of the modular assembly, so it's exact relationship to the trigger is not the same from frame to frame or even on the same frame with a different trigger module.

Poper said:

Common sense tells me it should be simple enough with the possibility of maybe a little stoning if something drags.

Click to expand...

Maybe, maybe not. See my reply above.

Poper said:

Would keeping the hand from the DAO fix this issue?

Click to expand...

The hand is part of the trigger module, but its fit to the cylinder and even the frame itself will be different from frame to frame, cylinder to cylinder.

It's all about production tolerances and how they stack up. You might get lucky and have everything just fall into place with no problems and perfect function. Or a little less lucky and have to do some fitting on the parts you have. A bit less lucky and have to replace some parts. Even the trigger hosing itself may require fitting to the frame in order to get an even contact around the edges of the joint. As automated as manufacturing is today there is still a lot of hand fitting for some things.

Bottom line - It won't hurt to try, but don't go in blind. And do not accept less than correct fit just to get by. Get the Kuhnhausen book or Ruger double action guns. It doesn't cover the GP100 specifically (unless it's been updated since my edition), but the similarities between the older Rugers and the GP is close enough for understanding the critical fit issues. Of course Ruger can possibly convert it for you since it is a current production gun. Wouldn't hurt to call them and ask.

Best advice is to try different things (i.e. hammer only, hammer/trigger unit, etc.) and see if it works. Not like you damage anything by experimenting.

I've swapped lots of Ruger DA action parts around. The trigger guard/fire control housing itself is usually uniquely fit, but often they do fit between similar vintage revolvers. The actual lockwork has very rarely ever not been a drop in fit, so you should have no problem transplanting the hammer and trigger together into the new frame. It's effectively exactly the same process as done at the factory.

Transplanting the trigger and hammer should only take you about 15 min. If the combination is out of spec and it doesn't work, you know. If they do work as I would expect, then you will know that instead. My bet is the two together will work, as they usually do.

Leave the hand alone, it'll carry slightly differently in the new trigger, but not significantly so to cause issues in ANY revolver I have done a transplant with.

I have swapped hammers on several Ruger double action revolvers and none of them have really required any fitting, not that it cant happen. The only thing that really needs to be swapped to convert it to SA/DA is the hammer, the trigger is the same. I would swap the hammer and test it for proper operation.