Gunsmithing Tikka T3 bolt shroud fitting

[boomfab]

I just bought a Tikka T3 sporter and replaced the factory plastic bolt shroud with a Lumley Arms nitrided steel shroud.

The steel shroud has a bit of wiggle when installed, which is normal. The shroud comes with a couple springs that you can try using at the back of the shroud to take up the slack.

I played with the springs and found that at full length, they wouldn't allow the bolt to cam down into battery. The more I trimmed the spring, the less force it took to cam down the bolt.


I removed the spring altogether and tried putting a little bit of Enos Slide Glide Lite grease inside the shroud and it reduces the wiggling by a lot!


Questions:

1) Will the tightness of the bolt shroud fitment affect accuracy of the gun at all?

2) In low temps, will using light grease inside the shroud cause failure to fires?

 

[cannoncrossfire]

I've designed and CNC machined Titanium Bolt shrouds for Tikkas here in Australia, and the shroud is pretty much always going to have some play in it, and this is because the firing pin/cocking indicator moves inside that shroud. I've found through testing many shrouds that the 'tighter' shrouds can slow down the cocking indicator from flying forward when the rifle fires - this can cause misfires. Some play in the shroud is what you want - it's safe. Too tight or too loose is bad. The firing pin assembly isn't perfectly concentric too, so the bore of the shroud needs to be a little large to allow for assembly/fitting as it clears the back of the firing pin/cocking indicator.

John.