[combatantr2]

No. 1
If the thumb safety is engaged, of course the hammer is open, is there a way the hammer would drop due to adverse mechanical reasons while the thumb safety is engaged?

No. 2
Why does the slide have to be locked while the thumb safety is engaged? Cant it just be safetied w/out locking the slide? Whats the purpose of this?

Thanks.

[jungle]

1. There is no way the hammer will drop with the thumb safety engaged in a normal 1911 style pistol. Take a close look at the hammer-two sear engagement surfaces, either of which would stop hammer movement, and a cut in the hammer that the safety rides in which will impair hammer movement if the sear breaks. Proper safety checks will ensure your pistol is functioning normally, if it is not then you already have a mechanical problem that could lead to a failure.

2. The thumb safety locks the slide purely through it's interaction with the safety cut in the slide. It prevents slide movement when the weapon is reholstered. In a normal 1911 moving the thumb safety on will lock the slide by design.

It's fun to wonder about the why of design or the intent of the designer, but your time is better spent learning the manual of arms for your particular weapon and sticking to it.

[1911Tuner]

If the hammer hooks break and release the hammer, the hammer will be impeded...a LITTLE...by the resistance of the plunger assembly as it engages the thumb safety. The safety will be pushed down to the disengaged position. At that point, the half-cock will arrest the hammer. If the half-cock is compromised...broken or deliberately removed...the hammer will fall to the firing pin. Whether or not it will fall hard enough to fire a primer after pushing the thumb safety to disengagement depends on how positively the plunger engages the safety's detent. If the safety moves off-safe easily, the hammer will knock the safety off with little impairment...but either way, the safety will drop.

Easy to confirm. Assemble the gun without the sear. Thumb the hammer back and hold it. Engage the safety, and release the hammer.

It's the half-cock that'll prevent an unintentional discharge from Condition One in the event of hammer hook failiure.

[jungle]

Tuner, glad to see you're feeling better.

Did you ever see or hear of a 1911 in good repair firing without help from the nut behind the trigger when cocked and locked?

[1911Tuner]

Heard of one just goin' bang while in a holster in Condition One? Nope. Never. Heard of/seen cracked sears and broken hammer hooks, but in every case, the half-cock stopped the hammer.

Did a little experiment once...Used a Dremel cutoff wheel to remove a full 1/8th inch from the sear nose and the hooks from a junk hammer. Not only did the half-cock stop the hammer 10 times in 10 tries, it would hold full-cock with a good hammer...and functioned normally for several magazines before the hammer started to follow.

Note that this does not apply to Series 80-type hammers. The half-cock is a quarter-cock shelf, and it lets the hammer get too close to the firing pin with a good sear. Removing .125 inch from the sear would let the hammer reach the pin, and possibly with enough force to light a cap.

[carebear]

jungle,

I've never thought about the "locking the slide for reholstering" aspect. :o

Even as I curse and have to remember to put my thumb on the back of the slide when reholstering my .380 (Gov and Mustang) Colts in softer IWB holsters. :rolleyes:

Guess that shows their lack of common heritage.

Thanks for the info.