Great post. Now how do I switch out the top lever spring.

Someone crafty should post all on youtube.

D. Landers
Austin, TX

Help-have a used DT 10 Berreta which shoots very well,having the same problem with with the lower barrel firing and then not firing .Have had 2 different gunsmiths look at a total of 4 times??have had new firing pins placed,but it still has a "click",with no indentation on the primer.replaced firing pin,but not the springs,what should I do??Very frustrating,but love the gun?steve clinch Omaha ne 402504-1470

Send it to Coles. Contact them for instructions.
http://www.colegun.com/

I found this write up VERY helpful, thank you Bill. While I did the job, I made a video which I am posting on you tube. Sorry about the focus, guess my camera doesn't get that close, but I think you can make out most of the details. Hope it helps more folks like me.
SD

[youtube]http://youtu.be/-ZFjp47LvfE
[/youtube]

An observation.
My 525 begain having FTF problems so i ordered new pins and springs. Took it all apart and inspected the old pins and compared length to the new pins a then found out that the overall length measurement dosent really tell you much about the wear on the old pins because of the angle that is ground on the hammer end of the pins. My old pins were pitted pretty badly on the primer end but i was suprised to find out that the worst damage to them was the hammer end was mushroomed out from the hammer strikeing it. It must be caused by the hardness of the primer being harder than the hardness of the hammer end of the pin because that is all the stops the pin travel. it can not be caused from dry firing because the hammer travel stops when the hammer bottoms out on the frame. The firing pin bore is deeper than the pin is long so dry firing cant mushroom the head of the pins as the bore is deeper than the pins are long.
The erossion on the primer end of the firing pins was only a very small part of the FTF problem on my gun. The main damage that caused the problem was the defromation of the other end caused by the soft material the pin is made of mrushromming out when it is struck by the hammer.

Today I noticed that the lower pin on my Citori 16 ga. is only lightly denting primers, and causing occasional misfires. The UPPER pin has a chip out of it. This after only about 500 rounds usage. (The gun is only 12 months old.) Friends at the club where I shoot, complained about my Mossberg Silver Reserve. THAT gun got 2000 - 2500 rounds out of each set of factory pins. I replaced the pins three times before I started machining and heat treating my own pins. After some experimentation, I got pin life up to about 7500 rounds, by using S7 shock resistant steel. I believe my Browing would also benefit from the same approach. Incidentally the pin design on the Mossberg is very slender (and delicate) compared to the Browning Citori. Citori pins, if made out of the right steel and heat treated properly should last a LONG time.

Yea it's amazing to me that all the citoris ever have any fire ring pin problems. The shock applied to them when they strike the primer is so small. I assume they are made of tool steel and as we were all taught in first year metal shop you can make and temper a chisel then drive it thru a 1/4" hot roll plate without dulling or breaking it. That is way more shock than a firing pin should ever indure so I can't belive that with all the material and expertise that they have available to them that browning dosent make firing pins that would last for countless thousands of rounds. I wish that I had available to me the equipment to make and temper my own I am sure that it would be very little trouble to make pins that would out live me be a long time. Something that I don't understand is why if they can make firing pins in A5s last for ever why not citoris?
Maybe I'm living a sheltered life but I have never had a problem with the many A5s I have owned and shot over many years and have never heard of anyone ever having to replace the firing pins on them.
What's up with that I wonder?

Thanks for this firing pin maintenance guide! I just finished cleaning the firing pins and the rest of the receiver on my Citori Trap. It was the first time I opened up an o/u but it went really well by following the instructions.

Bill,

I know this is an old thread but I just wanted to comment on having used the information to repair my gun.

I just replaced the lower pin and spring using your thread. I tried to get away with just cleaning both the pins and spring about two months ago but the problem of light primer dents returned. I measured the old pin with the new one and found it approximately 5k shorter than the new one.

Anyway, we appreciate your efforts in making this instructional guide!

Steve

my citori 425 does not break open. If i take the front wood off it does. Any Ideas ?
Everything looks to be where it should be on the forearm .

I had a superposed that started doing that. I had noticed for a long time that the lever had been past center for a long time and I had hell opening it some times. Thought it was the bottom firing pin so I replaced it but it didn't help much.
Wound up replacing the bottom sliding latch part that engages the locking lug on the barrels.
That fixed everything. Now it dosent lock up and not want to open and the lever is to the right like it is supposed to be.

Thank You . I will look into it.

I took the trigger assembly apart and followed the instructions on this post to clean the firing pins.
It turns out that the hammers were jammed and would not set backwards. I looked at the pictures on this post and noticed that when hammers are held back they move under the side rods. That was the problem. Everything was locked because the rods were pushed Backwards. Everything was out of "timing" . That's why the gun would not break open. I must have dry fired the trigger when I pulled out the trigger assembly the previous time. (bad move!!)
Now everything is working and the gun opens.
Thanks guys...!

I scanned these posts-did anyone ever say what size Phillips screwdriver is used to remove the pad off the stock?I am not sure but think someone told me that the newer Citoris's use a 6mm allen head to remove the main mechanism.Since I can't see the screws in my new BT99 I would appreciate any input from those who know.

I use a #2 phillips to remove the butt pad on mine

Having read all the posts in this thread, I have a 60's vintage Miroku like another poster. I bought the shotgun unfired and in the original box--it had been stored all these past 50 years or so. Just recently I had a total of 5 FTF--all in the lower barrel. 4 of those FTF's were on a recent SC outing where I fired 50 shells: 25 brand new AA's and 25 of my AA reloads. The 4 FTF's were all reloads using Winchester primers. When I inserted the failed shells in the top barrel and tried to fire them again, they did not fire there either. By the way, this is a 20 gauge O/U.

After reading this thread, I was going to try and clean the firing pins and channels but I cannot get the stock off. The head of the long caps crew has a big slot (like for a flat screw driver) and a small hole in the center. I tried to remove the bolt with a simple but large screw driver to no avail. Consequently, I am thinking of having my gunsmith do this work for me. However, I realize I may still have a problem with my reloads of AA's. (I also reload 28 gauge for my SKB and a Browning with no issues.). How can I address the possible reload issue? I really prefer AA's and have a big stockpile. Any comments would be appreciated--particularly from Curly who has helped me a lot in the past.

I'm guessing you have a badly gummed up receiver. 50 years of sitting unused can certainly do it. Take it apart and clean it well.

I can understand how 50 years of storage could create problems of dirt/rust. But why did this problem show up after several hundreds of rounds and why just reloads?

Primers could be set lower than the new shells, primers in new shells might be more sensitive to hits from the firing pin. Only a inspection, clean up and use will tell!

Great info! Saving for future use