1911 light primer strike issue

[vlady]

Question for you experts. After a few range trips and about 300 rounds of break-in, I'm starting to have some light primer strikes. This happened with a couple of different brands of ammo so I don't think that's the cause (used same ammo with another 1911 and worked flawlessly). The odd part is that if I pull the hammer back after the initial ftf, the round goes off. Any suggestions? I'm going to check the overtravel screw to see if it moved. This is a TM 80%

[pacrat]

Originally Posted by vlady

Question for you experts. After a few range trips and about 300 rounds of break-in, I'm starting to have some light primer strikes. This happened with a couple of different brands of ammo so I don't think that's the cause (used same ammo with another 1911 and worked flawlessly). The odd part is that if I pull the hammer back after the initial ftf, the round goes off. Any suggestions? I'm going to check the overtravel screw to see if it moved. This is a TM 80%

I'm kind of an answer the question with a question guy, so here goes.

Did you fully disassemble, clean, and properly lube the pistol when you got it? You'd be amazed at the dirt, crud, gummed up lube, and even metal shavings I've encountered "inside" new guns.

Doesn't take much of the above to "soften" the strike of a 1911 FP.

Failure to fire, then will go off on second strike, is common with a light pin strike. First strike dents primer cup, takes out the slack in the primer between the cup and anvil. Second strike sets it off as it should have first time.

Overtravel screw on trigger can keep the sear from tripping. But is out of the equation once hammer falls. It will not effect pin strike.

Sometimes a case of "not all primers created equal". Some have thicker, or harder cups than others and take more force to set them off. Some Euro brands especially. In which case a stronger hammer spring or weaker FP spring are needed for reliability with those brands.

[vlady]

I've stripped and cleaned the pistol after each range trip but as it was a hombuild off a 80% frame, no gunk as you would see in a store bought pistol.

[Bob Hostetter]

What weight of mainspring are you using and have you checked the overall length of the firing pin?

[pacrat]

Originally Posted by vlady

I've stripped and cleaned the pistol after each range trip but as it was a hombuild off a 80% frame, no gunk as you would see in a store bought pistol.

What weight hammer spring did you use" IIRC "standard" USGI is 23#. Many/most kits have lighter hammer springs. Some as low as 15#.

[vlady]

Firing pin checked out. The mainspring I believe is either 17 or 18.

[pacrat]

Originally Posted by vlady

Firing pin checked out. The mainspring I believe is either 17 or 18.

Did you use a steel pin or a titanium?

[vlady]

It's steel

[Nathan Krynn]

Originally Posted by vlady

Question for you experts. After a few range trips and about 300 rounds of break-in, I'm starting to have some light primer strikes. This happened with a couple of different brands of ammo so I don't think that's the cause (used same ammo with another 1911 and worked flawlessly). The odd part is that if I pull the hammer back after the initial ftf, the round goes off. Any suggestions? I'm going to check the overtravel screw to see if it moved. This is a TM 80%

Kind of spaghetti on a wall thing here as I would need to look at it. Did you fit the hammer all by itself so it has free ROM (range of motion) and not getting hung up on something?

[pacrat]

Q&A suggests you need a higher rated mainspring.

[ojisan]

Often when a round will fire on the second strike, the slide was not fully into battery on the first strike.
The first hammer impact fully closes the slide, the second fires the round.
If it worked fine for 300 rounds, my guess is everything is fitted OK.
I would check the front of the chamber for lead build up for the first step.

In general, I don't like most lightweight spring kits.
Wimpy hammer strikes and sluggish trigger returns are hardly worth the easier pull.

[vlady]

Originally Posted by Nathan Krynn

Kind of spaghetti on a wall thing here as I would need to look at it. Did you fit the hammer all by itself so it has free ROM (range of motion) and not getting hung up on something?

Hammer has perfect ROM. The pistol developed the light primer issue about 200 rounds into break-in.

[vlady]

I'll pick up a heavier spring and give it a try. Thanks everyone for the replies!

[xsefan]

Is the hole for the hammer pin round? Check to make sure it's not oval shaped.

[vlady]

It is round. Got the 23# spring in yesterday. Going to the range soon to test it out so i can strip everything and finally get it cerakated.

['ol shooter]

Take the recoil spring out of the picture, and run the slide by hand, to feel for drag at lockup. The locking lugs might be dragging a bit. I would take it down and inspect the lugs for damage, indicating a need for modifying the lugs or changing link length if they look like they are locking up too deep. This is where Kuhnhausen's books can be a lifesaver.

[vlady]

Originally Posted by 'ol shooter

Take the recoil spring out of the picture, and run the slide by hand, to feel for drag at lockup. The locking lugs might be dragging a bit. I would take it down and inspect the lugs for damage, indicating a need for modifying the lugs or changing link length if they look like they are locking up too deep. This is where Kuhnhausen's books can be a lifesaver.

Will do. I've inspected the link (had to change this to get proper lock up) and the lugs and all looks kosher. I'll try racking the slide sans recoil spring.