Leaving for antelope hunt in 4 days and having problems with my Tikka T3 300 WSM. It has a custom lija heavy bbl, so not factory chamber. I only fired it enough when I got it to know that it was going to shoot very good, so I sent it off to be fluted and then had barrel cryogenic treated. Gun shot great when I got it back together with maybe two misfires out of 20 reloads. Then tonight I wanted to chech my zero and had about 60% misfires. Tried some Winchester factory rounds and they were even worse, leaving a slight mark on the primer. Could the cryogenic treatment have weakened my firing pin spring? I have taking bolt apart and cleaned firing pin/spring , but still doing the same thing. Anyone have any ideas? I have other guns for the hunt, but this gun was shooting in the .3's and is really sweet.

How much firing pin protrusion do you have? How is the head-space since you had it re-barreled.

I bought it re-barreled, firing pin is protudes right at 1/10th of a in. Bolt/trigger was not on the bbl action when I had it cryogenic treated.

I would get a smith to check the head-space then go from there.

.100" is more than enough for firing pin protrusion.

270wsmnutt, are you sure your firing pin is measuring .100??? That would be dangerous and about .035 excess. FWIW they don't normally Cryo springs. When you reassmbled the bolt are you sure you reassembled it correctly?

http://www.tikka.fi/pdf/manuals/TikkaT3_RH.pdf

Go to page 22, read the instructions and make sure you are doing it right. I don't have a T3 on the premises at the moment so I can't check it out for you to see how everything sits or if the pin is adjustable. If it is, it could have been assembled wrong at some point.

One other thing to look at, The trigger could be interfering with the forward movement of the cocking piece. Make sure your over travel setting isn't so tight that it is interfering with the sears ability to drop cleanly and out of the way.

Again, I don't have a T3 on hand at the moment so my suggestions are based soley on things that are known to cause the problems you have mentioned. Good luck!

If I remember correctly, the two T3's I had, firing pin protrusion was right at .065". I don't believe overtravel was adjustable on the factory triggers, just the trigger weight screw, but I am in the same boat as Malm right now and don't have one at the shop.

Thanks for all of the info! I will have to wait until I get home from work to open the pdf file ( blocked for weapons!!!). I think that could have something to do with it, seemed really simple to assemble. But I think my problems did start after I took the bolt apart to bead blast handle and body to satin finish to match the stainless bbl. I'll follow the pdf instructions to take apart and clean good before I put it back together. If that does't work, my local Bass Pro said that they could check the headspace for $35.

Repeated on the springs... Those should have removed before the big freeze.

Some times oil will run in around the firing pin and soften
the primer strike. Try cleaning the bolt out and wiping out
any excess lube.

Mystery solved... I kept going back to what I did to the gun after it started the misfires. So I diassembled down to stripped bbl action and saw that the bolt wasn't rolling over enough for the hole in bottom of bolt to line up with the saftey lever. After about 2 dozen times of taking the bolt apart, I shined a flashlight in front of action/chamber area and noticed a bright shinny screw sticking down from the front scope base! Talk about feeling really stupid! Took it out and put in a shorter one, worked like a dream. All I had to do was look in the mirror to see my problem! Thanks to all of the replys and sorry for wasting your time.

Doh!

The alignment of the cocking notch is important. Besides interfering with the forward momentum of the firing pin, it is what causes bolt handles to jump when dry fired.

With a bolt lug colliding with a springy little 6x48 screw, you would think that you would feel that. Oh well, glad to hear you solved it.

Had the same base screw issue on a T3 with Talleys. Glad you found the problem.

Good deal!

Re-zeroed last night and wow, I love this gun! 3 shots in .3" at 100 again with 180 Nolser Bal Tip behind 64 gr of IMR 4350 @ 3,050 fps. I think that should get the job done on a antelope or anything else for that matter.