Grip Safety operation/ maintainence

[Lazlo]

Looking for ideas as to what may be causing this grip safety failure: With thumb safety engaged, hammer back, no movement in hammer or trigger. When the thumb safety not engaged, and the grip safety not engaged and hammer back, trigger will move and hammer will fall. When grip safety is engaged and hammer pulled, hammer falls as designed.
This firearm is a 74 Colt 1911 Series 70 Gold Cup National Match, and was purchased from an estate collection. I have yet to fire it, or field strip it, pending suggestions from this group. As always, a qualified gunsmith is in order, but I'm curious about the possible causes.
Thanks for your help and suggestions as to how to proceed are welcomed.
Lazlo

[cochise]

Welcome Lazio, there is a similar post below yours ( two I think), that might answer some of your questions. Check it out and then we can talk some more.



For your review.......:-)

http://www.youtube.com/watch?v=W0dZjfrnDik&NR=1

[Lazlo]

Jim,
Watched the video you suggested. Field stripped the firearm and inspected for broken sear spring. Upon disassembly, it was not seated in it's lower notch, having twisted itself away from it. I removed the grip safety, main spring housing, and thumb safety. I reseated the sear spring in the proper location, tested it for function, successfully, and reassembled. Tested it once more, grip safety still inoperable. Is there a way to "modify" (read disable) the grip safety, and is there a reason to do so? Having trouble trying to understand this.
Thanks,
Laz

[X-Mark]

Someone could have "sensitized" the grip safety a little to much.
To the point of making it non functioning.
You would have to look through the frame (with grips off) and see how the trigger bow is contacting the grip safety arm.
If you are unsure, its best to have a gunsmith take a look at it.
It would be cheaper for him to solder up the arm, and re-fit, than have it replaced.
I "sensitive" all my competition 1911s.
I have one that is pinned. You don't need a grip safety for USPSA
(keep your "carry" 1911 with a functional grip safety)

[dfariswheel]

To understand your problem.......
The grip safety is moving in and out of the frame properly, but when it's NOT depressed, the trigger will drop the hammer?

When the trigger is pulled, does the grip safety move inward ON IT'S OWN, or does it not move at all?

If so, here's some possible causes:

The safety has been altered. If the lug that engages the trigger and prevents the trigger from moving rearward is ground or filed, it can't block the trigger from moving.

The safety was a new one installed by a previous owner, it didn't fit properly, and the previous owner left it as-is.

In any case, the grip safety function is not complicated. The lug on the front of the grip safety contacts the rear of the trigger bow and blocks the trigger from moving to the rear.
When the grip safety is depressed into the frame, the lug is pivoted upward and our of engagement with the trigger, which allows the trigger to slide rearward.
If the safety is defective or has been altered it can allow the trigger bow to pass under the lug on the safety and may even push the lug up out of the way.

With the frame totally stripped, you can install the trigger and the grip safety and view the function.
A good purchase for a 1911 owner is to buy a copy of the Jerry Kuhnhausen book "The Colt .45 Automatic: A Shop Manual, Volume One".
This covers total gunsmithing on the 1911 pistol series and shows how everything works and how to correct it if it doesn't.
This is not just a reprint of a bunch off old GI manuals, it's all new info, and is the very best available. The repairs and techniques shown are those used by the Colt factory.
If you intend to own a 1911 pistol, this is the best money you can spend.

JERRY KUHNHAUSEN THE COLT .45 AUTOMATIC - Brownells

[Lazlo]

X-Mark and defariswheel: Thanks for the quick replies. Upon inspection this afternoon, the lug on the grip safety has been "sensitized" to the point of oblivion. Thinking this one must have been a race gun, as it also sports the squared trigger guard modification as well. 1974 Series 70 GCNM, and the trigger is outstanding. Won't be carrying it, for obvious reasons, but I'm leaning towards keeping it the way I found it. It's a keeper just the same.
Thanks again guys,
Laz