SVI INFINITY Problem.

[Jasonub]

whoops i mean shootersconntection. i just got one last month from chuck. sorry for the mistake, I also ordered some parts from speedshooter.

The sv extended firing pin is not available at speedshooter and someone in this forum said that the limcat will drop in, thus i ordered 1

I just got the firing pin and dropped it in the channel without the spring. it was ever so slightly binds near the end of the pin's travel

i just got my dremel out and used the rubber wheel to remove some material where it binds. viola

[rr4406pak]

Thanks for all the advice. It sure helps.

I tried:

1. Extended firing pin. Could not get it to work. Ordered a Dawson Precision Hyper pin and the thing did not fit. When installed with the firing pin spring the firing pin does not go in far enough to put the firing pin keeper on. Shooter's Connection insists they sent me the correct one but do not see how it can work. Do I have to cut the spring or something?

2. Replaced mainspring 17lb spring. DID NOTHING.

3. Replaced firing pin spring. DID NOTHING.

4. Adjusted overtravel. DID NOTHING.

So I spent this money on parts for nothing.

But I think I solved the problem by cutting the firing pin spring down so it is as long as the firing pin itself. I also changed to Federal small pistol primers (which are supposed to be softer).

The combination of these seems to have fixed the problem. Went through a box of bullets reliably.

I stumbled upon this solution by testing the hammer fall on the firing pin with the firing pin spring completely removed. When I did the "pencil test" it jumped out of the barrel and hit the ceiling as it should.

It still does not hit the primer nearly as hard as I would like.

What the heck is with these light, wimpy primer hitting SVI's???

[chuckbradley]

It was most likely the firing pin spring not cut short enough to begin with. With the IBF the firing spring has to be cut. Keep an eye on the breech face screw because when it works loose or breaks it will cause problems.

[scirocco38s]

It was most likely the firing pin spring not cut short enough to begin with. With the IBF the firing spring has to be cut. Keep an eye on the breech face screw because when it works loose or breaks it will cause problems.

Chuck, you are all over the problem as the SVI fp spring is shorter, if using a standard wolff fp spring you must cut at least 4 coils for it to work correctly. Sometimes more. I believe that whatever firing ping was in there was binding on the spring. I am actually surprised that you could assemble the topend of the gun without some difficulty. I have used wolff fp springs but the last time I ordered spare parts for my guns I just went ahead and purchased 6 extra fp springs from SV and now I am set for the foreseable future.

[titandriver]

I think post #4 nailed it!!!!

[rr4406pak]

Very funny titandriver! (You are the man though...)

It does not make sense though that the flawed configuration would work for so long and then, magically, start to fail.

If the FP spring was of the incorrect length from the start... why didn't it fail from the start? Why would the problem take so long to appear?

Don't get me wrong... I'm am glad it is working now... I just don't understand the physics behind it...