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Discussion Starter · #1 ·
So I have read the articles and watched the videos and I'm a bit perplexed with the timing on my 1919a4. I have an adjustable lock frame and I'm adjusting the timing to approx .072. However when I adjust it the way the articles and videos say to get it to drop at .072 with the gun assembled I have to set the trigger at approx .042. Do I have something a miss in there or what am I missing? The gun runs great when I adjust it as above.
 

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Are you using the USGI timing gauges ? timing is not typically "out" - I have only had to adjust a few triggers in 20 + years . It is a fairly simple process- if you have the video showing the process, ( as in where to place the gauge, easing the bolt forward) you check to see if the shoot / no shoot points are met. If not, adjust your trigger screw . I assume you go no go measurements are correct, and once set, should not change. Unless of course you change parts in the trigger frame - the adjustment screw the Israelis used is much easier than bending or swapping triggers.
 

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Did you watch this video?

 

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So I have read the articles and watched the videos and I'm a bit perplexed with the timing on my 1919a4. I have an adjustable lock frame and I'm adjusting the timing to approx .072. However when I adjust it the way the articles and videos say to get it to drop at .072 with the gun assembled I have to set the trigger at approx .042. Do I have something a miss in there or what am I missing? The gun runs great when I adjust it as above.
Was .042 the thickest you could go to make the sear trip?

If so, it sounds like 1 of your feeler gages might be getting between the barrel and the extension. Make sure they are both only between the trunion and the barrel extension.
Remember you have a window to set timing. Having it at .042 is ok that's Late Timing and will run the gun slower.

fwiw

Troy
 

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Don't sweat it

As long as the firing pin does not release with the thicker timing gauge in place you are ok. The no go measures .116. If you replace anything it is a good idea to check the timing and headspacing. Better safe than sorry. My friend was at the Sandy and he had a gun with an Izy lock frame and we still had to bend the trigger.???? Didn't have enough time to figure out what the real problem was. His gun was still in one piece when he went home. That's good I would say.
 

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Discussion Starter · #7 · (Edited)
As long as the firing pin does not release with the thicker timing gauge in place you are ok. The no go measures .116. If you replace anything it is a good idea to check the timing and headspacing. Better safe than sorry. My friend was at the Sandy and he had a gun with an Izy lock frame and we still had to bend the trigger.???? Didn't have enough time to figure out what the real problem was. His gun was still in one piece when he went home. That's good I would say.
I took it apart a couple of days ago and replaced the trigger, sear and sear spring one at a time to see if it would make a difference. It will not drop above .080 but I had to set it at about .040 so it would not exceed the .080. In other words my trigger will drop between about .04 and .08 there is not a definite spot at which it is a go or no go but a range.

I'm assuming that the bigger the space in which the trigger drops the faster the gun will run. Yes No? Up until it fires out of battery.

OK I went back and did some searching on here and found that what I'm doing is correct. If anything I may have the timing a little late so I will look at that again to avoid beating the gun up.
 

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Something just isn't right here. When a timing adjustment is made, checked, and double checked, it doesn't simply go out of adjustment. We may have some sort of component issue here. That said, did you disassemble your bolt and check the sear, sear spring, and firing pin assembly? Is everything in there clean with no crud or dirt present? Does the bolt slide easily within the receiver box with no dragging or hiccups? Again, is the receiver box interior squeaky clean?

When I make any adjustments to my ersatz Argie '28 and '17A1 they stay adjusted and don't move in any way. Timing and head spacing should always be checked, and necessary adjustments made, whenever any internal component is changed out.
 

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Discussion Starter · #9 ·
Something just isn't right here. When a timing adjustment is made, checked, and double checked, it doesn't simply go out of adjustment. We may have some sort of component issue here. That said, did you disassemble your bolt and check the sear, sear spring, and firing pin assembly? Is everything in there clean with no crud or dirt present? Does the bolt slide easily within the receiver box with no dragging or hiccups? Again, is the receiver box interior squeaky clean?

When I make any adjustments to my ersatz Argie '28 and '17A1 they stay adjusted and don't move in any way. Timing and head spacing should always be checked, and necessary adjustments made, whenever any internal component is changed out.
Everything is clean and the trigger, sear, and sear spring are brand new. Bolt moves freely and locks up as it should.

The timing is not going out of adjustment. When I set it with the feeler gauges in place, by the method shown in the video above, it drops at approx .04 while pulling up on the trigger and adjusting the lock frame screw out. When I check it with the screw locked in place the firing pin will drop from .04 all the way up and until .08 in which it will no longer drop. If I set the trigger as shown at .072 it will continue to drop way over the .120 limit.

There is not a a single spot at which it will drop or it won't drop. I'm assuming this has to do with the amount of pressure put on the trigger which is going to vary.
 

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Everything is clean and the trigger, sear, and sear spring are brand new. Bolt moves freely and locks up as it should.
The timing is not going out of adjustment. When I set it with the feeler gauges in place, by the method shown in the video above, it drops at approx .04 while pulling up on the trigger and adjusting the lock frame screw out. When I check it with the screw locked in place the firing pin will drop from .04 all the way up and until .08 in which it will no longer drop. If I set the trigger as shown at .072 it will continue to drop way over the .120 limit.
There is not a a single spot at which it will drop or it won't drop. I'm assuming this has to do with the amount of pressure put on the trigger which is going to vary.
The engagement of the trigger to sear is ramped. When a firm trigger pressure is applied, the firing point and timing will be consistent. But, when light squishy trigger pressure is applied the bolt, containing the sear, will close forward ever so slightly from the adjustment point before the ramped trigger end eventually causes the sear to disengage firing the weapon. I can now see how the timing will change as the shooter's trigger pressure gets lighter and lighter. Isn't that interesting?
 

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Timing and headspace.

I was trying to help someone at the Sandy who's gun would not hold timing or head space. Re-set and a couple rounds later out of timing again. I was about to swap out with my barrel extension but it was cease fire time so I had to go back to my spot. Funny how cease fires always come when you are trying to solve a tricky issue. Anyway when he got home he took the gun to a gunsmith who found a hairline crack through the threads in the barrel extension. I have always been suspect with the loose thread quality at the barrel and extension point. Maybe it's because a tight thread would crack the extension more readily. Duh!
 

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Timing and headspace

If you have a hardware store near you that has a good supply of drill bits or better yet reamer blanks a #32 drill bit or reamer blank is .116. You can use the shank of a #32 drill as a no go gage. If you use a #32 drill bit and trigger releases the firing pin, don't shoot that gun something is wrong.
 

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Headspace

I know this started as a timing issue but I wanted to mention my thoughts about the Youtube videos. I watched the video and I have to tell you there is only one safe way to set headspace and that is in the gun. Many people don't have the feel to set it outside. If you want to rough set it ,OK. But it must be checked again once the gun it back together. One click out at a time from failure to go into battery till it goes into battery. Then two more clicks out. I have seen guns come apart from setups made outside the gun. It's your 15G. Don't get lazy.
 
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