1911 Tuner, RIGHT ON Brother. You could start a school for 1911 mechanics. I love reading your views mainly because I have seen most of the weird problems people post on here and you are usually right on target. (And polite.) Everyone on this board should be very thankful that you take the time to read and post and help folks out. There is so much BS on the internet and you are a refreshing source of valuable information. (And apparently a lover of dogs also. Anyone who loves dogs is OK in my book.) Keep on sharing your views. And thank you.
1911 intermittent light/nonexistent primer strike
- Thread starter patrolman
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ClarkEMyers
Member
Next question is how slight is very slight? I'd expect none. Where is the corresponding impact surface and what does it look like?
I'd still try pins on the outside to give an idea of how square the hammer and sear are on fitup.
What sort of space, gap or step, exists at the join between the bottom of the firing pin stop and the rail? Is it possible the hammer in firing is driving the firing pin stop forward/down to raise the very slight burr? Is the firing pin stop moving around at all? Extractor clocking - mark with liquid paper or such to check if nothing else?
Firing pin stop position issues - up on cycling down on firing - would be consistent with a difference between hand cocked and cycled on the restrike.
Fit an EGW firing pin stop in accord with 1911 Tuner's directions found on this site - well worth doing in any case.
I'd still try pins on the outside to give an idea of how square the hammer and sear are on fitup.
What sort of space, gap or step, exists at the join between the bottom of the firing pin stop and the rail? Is it possible the hammer in firing is driving the firing pin stop forward/down to raise the very slight burr? Is the firing pin stop moving around at all? Extractor clocking - mark with liquid paper or such to check if nothing else?
Firing pin stop position issues - up on cycling down on firing - would be consistent with a difference between hand cocked and cycled on the restrike.
Fit an EGW firing pin stop in accord with 1911 Tuner's directions found on this site - well worth doing in any case.
patrolman
Member
clark,
slight is very slight. the corresponding impact surface appears to be at the very top of the hammer face. the very top of the hammer face has some of the finish worn off at the approximate width of the burr on the disconnector rail, but no damage beyond the finish.
there is a small gap (miked to ~.008 in) between the bottom of the firing pin stop and the disconnector rail. the firing pin stop is an EGW oversized.
will have to check the sear/hammer relationship tomorrow and report back.
again, I can't thank y'all enough for the help on this.
slight is very slight. the corresponding impact surface appears to be at the very top of the hammer face. the very top of the hammer face has some of the finish worn off at the approximate width of the burr on the disconnector rail, but no damage beyond the finish.
there is a small gap (miked to ~.008 in) between the bottom of the firing pin stop and the disconnector rail. the firing pin stop is an EGW oversized.
will have to check the sear/hammer relationship tomorrow and report back.
again, I can't thank y'all enough for the help on this.
patrolman
Member
okay, folks
rechecked the hammer and sear interface on the external pins and it looks nice and square. the primary and clearance angles on the sear look like they mate up with the hammer very well under magnification. back to the step between the FP stop and the disconnector rail. browsed through all my books on the 1911 and none are clear on what constitutes an acceptable amount of step. anybody out there know how much step (if any) is acceptable?
rechecked the hammer and sear interface on the external pins and it looks nice and square. the primary and clearance angles on the sear look like they mate up with the hammer very well under magnification. back to the step between the FP stop and the disconnector rail. browsed through all my books on the 1911 and none are clear on what constitutes an acceptable amount of step. anybody out there know how much step (if any) is acceptable?
Jim Watson
Member
Doesn't matter that I can see.
How can a small mismatch between the bottom of the firing pin stop and the disconnector rail affect ignition?
How can a small mismatch between the bottom of the firing pin stop and the disconnector rail affect ignition?
patrolman
Member
jim,
fair enough. was wondering this, though... is there any functional reason for the plane of the disconnector rail to meet the plane of the firing pin stop slot at a sharp 90 degree angle? was thinking that smoothing that sharp 90 degree angle (not rounding over, just relieving) with a stone may prevent that burr being kicked up again. any thoughts?
fair enough. was wondering this, though... is there any functional reason for the plane of the disconnector rail to meet the plane of the firing pin stop slot at a sharp 90 degree angle? was thinking that smoothing that sharp 90 degree angle (not rounding over, just relieving) with a stone may prevent that burr being kicked up again. any thoughts?
1911Tuner
Moderator Emeritus
If the burr you're referring to is the one pictured below...the mismatch isn't the cause. That comes from the hammer striking the disconnector rail after if rebounds off the grip safety.
The slide doesn't remain in contact with the hammer and cock it smoothly. It slams it backward past full cock, and the hammer bounces off the grip safety tang and hits the disconnector rail...still past full cock.
Then, as the slide returns to battery, it drops the hammer a small distance, and the sear catches the hooks.
This look like your burr?
The slide doesn't remain in contact with the hammer and cock it smoothly. It slams it backward past full cock, and the hammer bounces off the grip safety tang and hits the disconnector rail...still past full cock.
Then, as the slide returns to battery, it drops the hammer a small distance, and the sear catches the hooks.
This look like your burr?
patrolman
Member
1911Tuner
Moderator Emeritus
Same thing. The modern hardened slides take longer for the peening to show up...but it comes from the same situation, and doesn't have anything to do with the light strikes.
If the burr and mismatch are a concern...just use a smooth 6-inch mill file to blend and smooth the area.
Avoid removing material from the disconnector rail forward of the slot. Blend only at the rear corner to the rear edge of the slot. If the rail is cut down too far, the disconnector won't disconnect when the rail rides over it.
If the burr and mismatch are a concern...just use a smooth 6-inch mill file to blend and smooth the area.
Avoid removing material from the disconnector rail forward of the slot. Blend only at the rear corner to the rear edge of the slot. If the rail is cut down too far, the disconnector won't disconnect when the rail rides over it.
patrolman
Member
tuner,
10-4
10-4
patrolman
Member
tuner, would this explain...
Tuner,
per your last post on this thread, would this condition (hammer being slammed past full cock, then resetting on full cock upon contact with the sear) cause a burr on the sear where it contacts the hammer hooks? have noticed a very slight burr along the length of the sear where it contacts the hammer hooks.
Tuner,
per your last post on this thread, would this condition (hammer being slammed past full cock, then resetting on full cock upon contact with the sear) cause a burr on the sear where it contacts the hammer hooks? have noticed a very slight burr along the length of the sear where it contacts the hammer hooks.
1911Tuner
Moderator Emeritus
Unless the sear is soft, it shouldn't.
The hammer doesn't rebound and fall directly back to the sear. The center rail in the slide catches it, and drops it onto the sear as the slide rides forward to battery.
Several years ago...and it may still be practiced by some today...the smiths who did precision trigger work on Bullseye-class pistols reworked the hammers so the drop from the center rail back onto the sears was no more than .003-.005 inch in order to preserve the delicate sear and hook interface. I haven't seen this done in a long time, but then...I don't have a lot of contact with pure target pistols any more.
The hammer doesn't rebound and fall directly back to the sear. The center rail in the slide catches it, and drops it onto the sear as the slide rides forward to battery.
Several years ago...and it may still be practiced by some today...the smiths who did precision trigger work on Bullseye-class pistols reworked the hammers so the drop from the center rail back onto the sears was no more than .003-.005 inch in order to preserve the delicate sear and hook interface. I haven't seen this done in a long time, but then...I don't have a lot of contact with pure target pistols any more.
rcmodel
Member in memoriam
Check and make sure your trigger stop screw isn't set too close and letting the half-cock hook whack the sear every shot.
That is probably the most likely reason for sear damage like you describe.
Hold the trigger tight back and move the hammer up & down while feeling for a slight "tick" when the half-cock notch goes by the sear. If you can feel anything at all, the trigger stop is set to close.
rcmodel
That is probably the most likely reason for sear damage like you describe.
Hold the trigger tight back and move the hammer up & down while feeling for a slight "tick" when the half-cock notch goes by the sear. If you can feel anything at all, the trigger stop is set to close.
rcmodel
patrolman
Member
am going to the range today to fire off another 100 rounds of white box. so far, have swapped the xp fps for a standard power wolff unit. also have in the bag a 25 lb mainspring and will swap to that if necessary. will report back if I get any more misfires.
tuner, per your last post, how was the hammer reworked to allow that .003-.005 drop from the disconnector rail to the sear? I am interested in the mechanics of such an adjustment.
rcmodel, when I installed the hammer, i did that check and can feel no grittiness at half-cock, but I'm by no means an expert (hence, this thread
). beyond feeling for grittiness, is there another way to check to see if the overtravel screw is not allowing full clearance of the sear?
tuner, per your last post, how was the hammer reworked to allow that .003-.005 drop from the disconnector rail to the sear? I am interested in the mechanics of such an adjustment.
rcmodel, when I installed the hammer, i did that check and can feel no grittiness at half-cock, but I'm by no means an expert (hence, this thread
). beyond feeling for grittiness, is there another way to check to see if the overtravel screw is not allowing full clearance of the sear?1911Tuner
Moderator Emeritus
Pretty simple, really. A little material is removed from the hammer on an agreeing angle with center rail with the hammer resting on the rail. You can hand-cycle your slide and see how far past full-cock that it pushes the hammer...and what modification it would take to leave the hammer closer to the sear when the slide moves off the hammer.
rcmodel
Member in memoriam
Well, if you can't feel it, it probably isn't hitting it.
But it's not "grittyness".
More like a little "tick" when the half-cock notch pushes the sear out of the way when you let it down by hand.
Is your bur running all the way across the sear?
Or just in the two ends where the full-cock notches engage?
If it's all the way across, it has to be the half-cock notch hitting the sear due to one or more of the following:
* Trigger stop adjusted too close.
* Hammer hooks cut down too far.
* Hammer half-cock hook not in spec. (Hook too thick)
If the burs are only on the outer ends where the full-cock notches engage the sear:
* Soft sear.
* Or,
* Did you radius the bottom edge of the EGA stop?
(just went back and looked at your picture in post #32. Edge is still square!)
If it is still very square like they come, the hammer is being dropped suddenly with full force on the sear as the slide / FP stop clears it.
That might whack the sear edge hard enough to raise a bur on each side.
I don't know.
Tuner?
PS: Have you considered getting an Old Priest and a Young Priest to take a look at it?
rcmodel
Ske1etor
Member
I wish I knew half of what 1911Tuner has forgotten...
I have learned a LOT while reading this thread.
I have learned a LOT while reading this thread.
JackOfAllTradesMasterAtNone
Member
I'll second that! RC, Dfaris, Tuner, Jim... The list goes on! Some very qualified, experienced, tallented folk on this list that seem quite ready to help anyone.
I have to thank Patrolman too. It's his project that's allowing the rest of us the opportunity to catch but a glimpse of the shadows of knowledge within those 1911 specialists. Mr. Browning would be proud for such a following.
-Steve
patrolman
Member
tuner,
thanks for the info. will examine that after I get the pistol up and running 100%.
a warehouse of knowledge you are, sir.
rcmodel,
took your advice and filed (as the trigger overtravel stop is fixed) another ~1/32 off the overtravel stop to ensure clearance. will examine the sear again after the range. thanks for the info. a warehouse of knowledge you are too, sir.
also, I will third the comment made by ske1etor and supported by "jack". just amazing the wealth of knowledge of everybody who has thrown their input into this thread. just as amazing the willingness of those folks to share that knowledge.
thanks for the info. will examine that after I get the pistol up and running 100%.
a warehouse of knowledge you are, sir.
rcmodel,
took your advice and filed (as the trigger overtravel stop is fixed) another ~1/32 off the overtravel stop to ensure clearance. will examine the sear again after the range. thanks for the info. a warehouse of knowledge you are too, sir.
also, I will third the comment made by ske1etor and supported by "jack". just amazing the wealth of knowledge of everybody who has thrown their input into this thread. just as amazing the willingness of those folks to share that knowledge.
1911Tuner
Moderator Emeritus
Wouldn't be enough to be a concern, since the slide is stripping a round and moving pretty slow at that point.
heh I wish I could remember half of what I've forgotten some days.
rcmodel
Member in memoriam
Well, could be.
I think I'd still put a little radius on the edge of it to ease the transition back to the sear, if it was mine.
Whatever is going on there in the picture in post #32 must be doing a lot of strange things to the hammer when it rides over it.
rcmodel
I think I'd still put a little radius on the edge of it to ease the transition back to the sear, if it was mine.
Whatever is going on there in the picture in post #32 must be doing a lot of strange things to the hammer when it rides over it.
rcmodel
patrolman
Member
It Works
just got back from the range. per rcmodel's advice, took an old priest and a young priest with me. young priest couldn't take the pressure and bailed. old priest hung in there for awhile. pistol fired 100 rounds of white box without a misfire. seems the standard power firing pin spring did the trick. just out of curiosity, i installed the heavier (25 lb.) mainspring in the pistol and swapped back for the extra power firing pin spring, thinking that the extra weight on the mainspring would propel the hammer with enough force to overcome the xp firing pin spring. another 100 rounds without a hiccup! it appears that the pistol is up and running. MANY THANKS to rcmodel, tuner, fuff, jim, clark, and everyone else who helped me out. this is a great forum!
am considering keeping the 25 lb mainspring/xp firing pin spring setup in the pistol, so on a final note, will there be any issues long-term with the 25 lb. mainspring? too much stress on the hammer strut? on the hammer?
just got back from the range. per rcmodel's advice, took an old priest and a young priest with me. young priest couldn't take the pressure and bailed. old priest hung in there for awhile
. pistol fired 100 rounds of white box without a misfire. seems the standard power firing pin spring did the trick. just out of curiosity, i installed the heavier (25 lb.) mainspring in the pistol and swapped back for the extra power firing pin spring, thinking that the extra weight on the mainspring would propel the hammer with enough force to overcome the xp firing pin spring. another 100 rounds without a hiccup! it appears that the pistol is up and running. MANY THANKS to rcmodel, tuner, fuff, jim, clark, and everyone else who helped me out. this is a great forum!am considering keeping the 25 lb mainspring/xp firing pin spring setup in the pistol, so on a final note, will there be any issues long-term with the 25 lb. mainspring? too much stress on the hammer strut? on the hammer?
rcmodel
Member in memoriam
I'd think 2 extra pounds isn't going to hurt anything at all.
If it works, don't fix it.
rcmodel
If it works, don't fix it.
rcmodel
patrolman
Member
rcmodel,
10-4. again, thanks.
10-4. again, thanks.
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