I have a SS 4.2” GP100 that I bought new about 5 years ago.
One of the first things I did after bringing it home was install Williams Fire Sights fiber optic sights front and rear. In single action it is one of my favorite handguns to shoot. The sight picture in adequate light is precise. The heaviness makes .38 special tame and full-house .357 manageable.
The single action trigger has always seemed adequate.The double action trigger pull on the other hand, was almost unusable, even after the thousands of rounds I’ve put through it and dry firing I’ve done.
I happened to pick up a Match Champion, a Smith, and a new Colt King Cobra last week and it made me realize how awful the trigger was on mine. So, i reached out to a local gunsmith about doing a trigger job. He was backlogged as is everyone at this time. So I decided to tackle the job myself.
I ordered a set of springs from Wilson Combat and started reading and watching everything I could about the subject while I waited for them to arrive. I found a pdf called Lowegan’s book of knowledge that thoroughly detailed the inner workings of my gun and gave general advice about improving the action.
The day before the springs arrived, I almost completely disassembled my revolver (for the first time ever) and cleaned everything thoroughly. I then took a Dremmel tool with a felt polishing tip and polished all the recommended touch points with Flitz paste to smooth out the action. I was careful to avoid taking any metal from the hammer and sear. It was easy to see where the trigger parts had been touching so I polished those really well. I also smoothed out the trigger return housing by hand-turning a 13/64 drill bit inside the cavity.
I then put it back together dry and clean to see what effect the polishing had. There was a noticeable difference. The DA pull was still heavy but it was much smoother. The SA break was crisper as well.
The next day the springs arrived. I installed a 10# hammer spring and an 8# trigger spring, lubed everything with oil, and went to test reliability. 4 out of 100 rounds loaded with CCI 550 small pistol magnum primers failed to fire in double action. So, when I got home I removed the 10# hammer spring and installed the 12#.
Here are the before/after lbs.of pull at each stage with a subjective feel description:
Stock (14# hammer spring,12# trigger return spring, no internal polishing, 5 years of use)
• DA - 12 + with a long, 3 stage, heavy pull
• SA - 6 with a fairly okay break
After polishing internals:
• DA - 11.5 with a smoother 2-stage pull
• SA - 5.6 with a crisper, cleaner break
With 10#/8# spring combo
• DA - 8.3 with a less pronounced stack at the end
• SA - 3.8 crisp and clean
With 12#/8# spring combo
• DA - 9.5 with the same slight stack as 10# spring, a little disappointingly heavy compared to 10# spring but WAY better than with stock spring
• SA - 4.3 with same crisp and clean break
I could probably do way better with some shims where appropriate. Stoning internal touch points would be more effective also but fear of taking off too much metal makes me nervous. Still, I achieved a DA trigger I can actually use and a much improved SA trigger pull. I would compare my results with the 10# hammer spring installed with the Smith’s trigger I tried. I suppose I could reinstall it and use softer Federal primers exclusively. Maybe soon I’ll get into it again and try to make the 10# spring reliable with all primers. For now though, I’m happy with the improvement I made.
Cost:
Springs - $9.99 + $9.99 shipping
Dremmel tool and attachment - $54
Flitz - $9
Total - $83
One of the first things I did after bringing it home was install Williams Fire Sights fiber optic sights front and rear. In single action it is one of my favorite handguns to shoot. The sight picture in adequate light is precise. The heaviness makes .38 special tame and full-house .357 manageable.
The single action trigger has always seemed adequate.The double action trigger pull on the other hand, was almost unusable, even after the thousands of rounds I’ve put through it and dry firing I’ve done.
I happened to pick up a Match Champion, a Smith, and a new Colt King Cobra last week and it made me realize how awful the trigger was on mine. So, i reached out to a local gunsmith about doing a trigger job. He was backlogged as is everyone at this time. So I decided to tackle the job myself.
I ordered a set of springs from Wilson Combat and started reading and watching everything I could about the subject while I waited for them to arrive. I found a pdf called Lowegan’s book of knowledge that thoroughly detailed the inner workings of my gun and gave general advice about improving the action.
The day before the springs arrived, I almost completely disassembled my revolver (for the first time ever) and cleaned everything thoroughly. I then took a Dremmel tool with a felt polishing tip and polished all the recommended touch points with Flitz paste to smooth out the action. I was careful to avoid taking any metal from the hammer and sear. It was easy to see where the trigger parts had been touching so I polished those really well. I also smoothed out the trigger return housing by hand-turning a 13/64 drill bit inside the cavity.
I then put it back together dry and clean to see what effect the polishing had. There was a noticeable difference. The DA pull was still heavy but it was much smoother. The SA break was crisper as well.
The next day the springs arrived. I installed a 10# hammer spring and an 8# trigger spring, lubed everything with oil, and went to test reliability. 4 out of 100 rounds loaded with CCI 550 small pistol magnum primers failed to fire in double action. So, when I got home I removed the 10# hammer spring and installed the 12#.
Here are the before/after lbs.of pull at each stage with a subjective feel description:
Stock (14# hammer spring,12# trigger return spring, no internal polishing, 5 years of use)
• DA - 12 + with a long, 3 stage, heavy pull
• SA - 6 with a fairly okay break
After polishing internals:
• DA - 11.5 with a smoother 2-stage pull
• SA - 5.6 with a crisper, cleaner break
With 10#/8# spring combo
• DA - 8.3 with a less pronounced stack at the end
• SA - 3.8 crisp and clean
With 12#/8# spring combo
• DA - 9.5 with the same slight stack as 10# spring, a little disappointingly heavy compared to 10# spring but WAY better than with stock spring
• SA - 4.3 with same crisp and clean break
I could probably do way better with some shims where appropriate. Stoning internal touch points would be more effective also but fear of taking off too much metal makes me nervous. Still, I achieved a DA trigger I can actually use and a much improved SA trigger pull. I would compare my results with the 10# hammer spring installed with the Smith’s trigger I tried. I suppose I could reinstall it and use softer Federal primers exclusively. Maybe soon I’ll get into it again and try to make the 10# spring reliable with all primers. For now though, I’m happy with the improvement I made.
Cost:
Springs - $9.99 + $9.99 shipping
Dremmel tool and attachment - $54
Flitz - $9
Total - $83
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