Sport king 100 feeds but wont fire 2nd round

[CLD1961]

I am working on a High Standard Sport King 100. The first round chambers and fires,the second round chambers but wont fire. This is also the first High Standard i have worked on.

[lonestardiver]

Is there any sign of a firing pin strike on the second round?

[03man]

Originally Posted by CLD1961

I am working on a High Standard Sport King 100. The first round chambers and fires,the second round chambers but wont fire. This is also the first High Standard i have worked on.

It would be helpful to know the ammo you are using, SV or HV?

Is the chamber clean? Test by loading an unfired round by hand with the slide back, point up, the cartridge should fall freely from the chamber.

[LDBennett]

Check that the slide is fully closed for that second shot. If not the firing pin has to fully seat the cartridge, loosing some of its energy and left with not enough to set off the primer in there rim.

Several things might cause the slide to not fully close. The common one is the magazine lips are not tuned correctly and they allow the soft lead bullet nose to hit the edge of the chamber, deform it and keep the cartridge from fully seating in the chamber. There is also the possiblity that the chamber is dirty enough to slow the entrance of the cartridge into the chamber. Then there is the recoil spring which should be changed out when you first get the used gun and every 10 to 15 thousand rounds thereafter. The recoil spring is in a tight cavity where the sides of the coils wear away, reducing the recoil spring strength.

Then there is the ammo issue. Perhaps the ammo you are using is under powered. But these guns need Standard Velocity ammo (not High or Hyper) as extended use with a worn out recoil spring and/or High or Hyper Velocity ammo can eventually cause a frame crack (well documented, unfortunately). CCI Standard Velocity is the GO-TO ammo for this gun because it is the least expensive accurate reliable readily available Std Vel ammo on the market.

So....Replace the recoil spring, clean the chamber until it will pass the plop test (dropping a live cartridge into a vertical barrel with a resultant "plop" as it falls home) and chamber live rounds at the range (gun pointed down range) and immediately extract them and look for excessive marks on the soft lead bullet where it might have hit the chamber edge during loading. Tune the magazines to minimize or eliminate poor ammo feeding. You can also inspect the second round right after it feeds doing shooting. Pushing the slide home after every shot with the thumb may reveal if it is the lack of the cartridge fully seating that is the problem.

If all of that does not fix the gun then come on back for more help. Its what we do here!

LDBennett

[Alan Aronstein]

I will add a few other possible issues !!! 1) Dirty or Rusted FP Channel 2) Broken or Bent FP Retainer Pin 3) Broken FP 4) FP Damage to the Breech Face from Dry Firing or a Broken FP. - Alan Aronstein

[CLD1961]

Thanks for all the info.i pulled the bolt assy. and can hear the firing pin moving i will take a look at that while doing a cleaning. and plop test Thanks.

[Ontarian50]

Do you hear a definite click as the hammer falls onto the firing pin on that second round? I would wonder if the slide isn’t cycling fully back to properly cock the hammer on that second round - whereas it cocks fully when you cycle the slide by hand. Maybe a worn sear surface isn’t catching.
However, if the hammer drops properly, then yes, you’re not getting a proper strike on the cartridge for likely one of the reasons posted above.