Ruger Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter · #1 ·
I did some searching but can't find the answer to my questions and I'm fairly new to revolvers.
I just purchased a GP100 Match Champion in 10MM. When I first bought it I test fired it with 10MM reloads and didn't have any issues with FTF but the trigger action was really heavy and gritty. I purchased a spring and shim kit from Mcarbo and slightly polished the trigger parts and installed the springs and shimmed the trigger and it made a huge difference. I brought it the range with some 40 S&W reloads and out of 24 rounds I had one or two light strikes. I only loaded 24 to test fire and chrono the loads.
I tried some Aguila factory loads and out of 12 rounds I had 9 light strikes that didn't even fire after several tries.
Brought it to an IDPA practice with 40 reloads and had several FTF in about 70 rounds, one that wouldn't fire after several hits.
I'm using Federal primers and TK .035" and .050"moonclips, which moonclips would/should be best? Some rounds are difficult to load in the .050" clips with my BK Mooner so I'm leaning toward the .035". I don't have any Ruger moonclips.
I have a Wolff spring kit coming and plan to change the hammer spring out but the only problem is I don't know what weight the Mcarbo kit comes with since they don't specify in their listing. I've been reading that the 10# spring is the best for reliability so I'll start there.
The light strikes (see pic) have me confused and is making me wonder if I have enough firing pin protrusion. I see where removing some material from the hammer step can alleviate that issue but don't want to go there yet since once you remove the material there's no going back. If I do have to go that route, how much do you remove at a time. I'm guessing .005"?
I plan on doing more methodical loading and shooting and keep better track of my results. I'm just getting started and would appreciate any input and suggestions others that have gone this route have found.
Thanks in advance!!

40 S&W Misfires.jpg
GP100 hammer 2.jpg
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #4 ·
Yea, I'll start with changing to the stock hammer spring. That makes most sense and is pretty easy to do. Then work my way to lighter springs and keep track of results.
 

·
Registered
Joined
·
1,972 Posts
As noted above the MCarbo mainspring is 9.5 lbs. Wolff makes 9, 10, 11 and 12 lb mainsprings. In talking with gunsmiths the general consensus is that firing pin protrusion should be a max of 0.055" from the recoil shield. Minimum headspace should be 0.060" and I think Ruger specs endshake range of 0.004" to 0.008". All of these can affect ignition. Also, the moon clip springiness can affect the amount of spring weight required for reliable ignition so what works in a conventional revolver may not in a moon clip one.

But, before getting into these areas I would consider the moon clip thickness and what works. I am not familiar in this area so perhaps seek advice from those having this model on what they use.
 

·
Registered
Joined
·
635 Posts
I have a 10mm Match Champion. I have a 12# Wolff hammer spring, 8# trigger spring. I have shimmed the hammer and hammer dog, polished the interior parts, and taken .020" off of the hammer step. All of this has given me an 8# DA trigger pull. I don't have light strikes with Federal Large Primers and Winchester small primers work in those cases that use small primers. I use .036" Ranch Moonclips which also work with 40 S&W. I have cut down the hammer step .020" on all my Ruger revolvers. It provides a more positive hammer strike without any decrease in safety.
 

·
Registered
Joined
·
3,213 Posts
You did the trigger job .... Try going back to factory springs ... Too Light = Light strikes .
And make sure , when you reload your ammo , to seat primers all the way down into the primer pocket ... seat them until they hit bottom and then give a little extra seating pressure .
When a primer isn't in the bottom of the pocket = light strike = FTF .

Clark Custom Guns can fix it with a sweet trigger job ... this is my preferred method of trigger fix , them boy's know their way around trigger jobs ... I can attest to that fact .
Gary
 

·
Registered
Joined
·
119 Posts
In my GP100MC 10mm I'm running the same set-up as CtYankee - 12# main spring with an 8# trigger return. I use Ranch products moon clips - I have no idea the thickness, but I think they only offer them one way. I do know the cost differential between Ranch and anybody's EDM wire cut clips - it's huge.

Adios,

Pizza Bob
 

·
Registered
Joined
·
2,026 Posts
Forgive me if I'm ignorant on this, but looking at the picture, I really only see one case that I would call a light strike. Is the perspective fooling me?
 

·
Registered
Joined
·
635 Posts
In my GP100MC 10mm I'm running the same set-up as CtYankee - 12# main spring with an 8# trigger return. I use Ranch products moon clips - I have no idea the thickness, but I think they only offer them one way. I do know the cost differential between Ranch and anybody's EDM wire cut clips - it's huge.

Adios,

Pizza Bob
Ranch Moonclips are .036" and the steel seems to be a lot harder - it certainly is less susceptable to bending.
 

·
Registered
Joined
·
1,972 Posts
" steel seems to be a lot harder - it certainly is less susceptable to bending. " CtYankee

That is a variable to consider. Softer moon clips would absorb part of the hammer blow and could cause FTFs.
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #14 ·
" steel seems to be a lot harder - it certainly is less susceptable to bending. " CtYankee

That is a variable to consider. Softer moon clips would absorb part of the hammer blow and could cause FTFs.
This makes sense. I need to look into the Ranch moonclips. The TK .032" moonclips are soft and I've had to "reshape" some already to hold the rounds in place.

I replaced the 9.5# Mcarbo spring with a 12# and the light strikes went away. Only increased the trigger pull about one pound which I can live with. The smoothness of the reworked trigger components makes most of the difference.

So, am I correct to assume using the the solid .050" TK moonclips in effect extend the firing pin protrusion .018"? The cylinder still closes easily when using them.
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #15 ·
Forgive me if I'm ignorant on this, but looking at the picture, I really only see one case that I would call a light strike. Is the perspective fooling me?
No one that askes questions is ignorant.
Some of them are less that others but all of these primers in comparison to the rounds that fired are much less pronounced.
 

·
Registered
Joined
·
1,972 Posts
"So, am I correct to assume using the the solid .050" TK moonclips in effect extend the firing pin protrusion .018"? The cylinder still closes easily when using them. "

I do not have a moon clipped model so cannot answer for certain but logically it would make sense. On the other hand that would be quite a variable to allow for in the headspace of the revolver. It may depend upon whether the cartridge in the GP headspaces off the moonclip or off the case mouth inside the chamber. If the latter than clip thickness should not affect headspace of the cartridge.
 
1 - 16 of 16 Posts
Top