S.A.M Commodore falling to half cock?

[cr810h4ll]

I've just come into possession of a pretty nice Commodore and in the course of using it for the past few weeks, I've just noticed a problem the other day. When I attempted to fire and use a slow, deliberate pull on the trigger, the hammer falls and fires normally. However, if I attempt to do any sort of fast firing, and pull the trigger relatively fast or with any strength, the hammer will fall to half cock and will not fire unless I pull the hammer back again and attempt with a smooth pull. I normally target shoot with the controlled manner, but I'm more concerned if I were to ever need to pull the trigger without thinking, it wouldn't fire as it should. Has anyone experienced this before?

The only thing I've done with it has been to field strip it to clean it after firing about 300 rounds through it.

[crazy birddog]

i have not yet, i got over a thousand rounds in my elite model, no problems yet

[toolman]

Does your trigger have an over travel adjustment screw? The first thing that comes to mind is the over travel adjustment screw has worked it's way in to far (they do that sometimes). Look for a small hole in the face of the trigger with a tiny allen head screw down inside the hole. If you do have one, use an allen wrench to back the adjustment screw out a little bit at a time and see if this helps.

[David Rose]

cr,

Just today I finished with a Commodore that was dropping the hammer all the time, not just during rapid fire.

Here is what I found. The sear spring was not firmly adjusted on the center finger. (Adjusting it did not correct things.) The hammer hooks had .017" depth. These should have been closer to .025". The sear was rounded and beaten to a pulp. The trigger bow was around .050" too long. The disconnector barely had enough length to function.

In this case the customer wanted to replace parts instead of repairing them. With a new hammer, sear, disconnector, trigger and sear spring, things functioned very nicely.

Hopefully, yours will not need all this. Look at the sear and see if it is clean and flat where it should be. Make sure there is good contact with the sear spring. See if hammer hooks are reasonable in length. Check that trigger bow length.

If any of this is beyond your capabilities, take it to a gunsmith. Just be prepared for some possible major reconstruction if things are very bad.

David

[cr810h4ll]

Thanks David,

I actually emailed SAM the other day and just got their response this morning with yours and they suggested the sear spring too. So I'm gonna take it down and see if that'll fix things up! I'll update when I get things changed around.

[cr810h4ll]

Just wanted to update, got everything working again, it was the sear spring like suggested. I guess time has taken it's toll on it and all it needed was to be tightened up a bit and it's working like a champ now! Thanks to everyone for their suggestions!

[John]

Order yourself a Colt sear spring from Brownells and install it in your pistol. A sear spring that gets loose, is not a good thing.

[1911Tuner]

A new sear spring may or may not help. cr8 and David provided two important "clews" here.

However, if I attempt to do any sort of fast firing, and pull the trigger relatively fast or with any strength,

And:

The trigger bow was around .050" too long.

If the trigger bow is long/out of spec...OR...if the trigger stop that's built in to the grip safety lets the trigger travel too far rearward, the stirrup can contact the sear spring and push it away from the disconnect. If the disconnect drops out of the connected position, the hammer falls to half-cock.

Here's why:

During the initial trigger pull...before the bow touches the sear spring...the sear rolls out of contact with the hammer hooks. This is a good thing. As the trigger travels further to the rear, the bow lifts the spring off the disconnect. The disconnect has nothing bearing against it to force it to maintain position. As the sear rotates, the feet angle backward at the bottom, creating a camming surface that the disconnect spade can slide downward on. As the trigger continues to push the disconnect rearward...it does just that.

The contact area...or overlap...of the disconnect and the sear feet is small, so the disconnect doesn't have to drop very much in order to lost contact with the sear.
Once that contact is lost, the sear corwn resets back into the hammer and grabs the half-cock notch.