Clickers...

[nksmfamjp]

A clicker is a tight case that is stuck in the chamber. The bolt makes a clicking sound when the extraction cam pops the case free. In normal use, your extraction cam is not used.
Most of the time they are caused from an interference fit at the base of the case and chamber. The main cause of this is a sizing die that is oversived in that area. They typically wont show up until 3-5 reloadings of the case.

Thanks Alex.

IME, there are several causes of clickers. If farther forward, where the die is sizing, it is just no sizing enough.

...but what if it is below the die in the web...do chambers need to be tight down to the web, but some amount oversized below the 0.1 line? Are case webs accurate enough across the lots and multiple suppliers to cut it within the springback allowance? Is this also hampered by our desire to run these things at 65000 psi without test equipment?

Just wondering.

 

[Alex Wheeler]

Usually the bottom .150" or so is not inside the chamber. The more solid web that is in the chamber the more likely you are to get into clickers. When you run high pressures you can expand the web and that brings the brass above it with it. Its harder to size that stuff too because more of the web is in the die which limits the size of the die. Theres a correct recipe for chamber size and die size for each cartridge and brass manufacturer. Tightening up the base can help or hurt, you just have to work through each one.

 

[Seabeeken]

A while back I heard of a guy who was using 25 CM brass in a 250AI. They are very similar but a few thou different. I decided to try it. Clicker every time and measuring showed the CM brass was .003 larger at the web and was causing the problem. Went to 250 savage brass and problem went away. As an experiment, I turned of .003" from the web area and just forward of it on a lathe and problem went away. Not thinning brass to make it work, Ill stay with the 250 brass. Just too tight at the chamber mouth.

 

[ELoodo]

I had this issue years ago on a single shot savage 12 lrpv in 22-250. Took me awhile to discover the probLem was with primary extraction. Got a new bolt handle, problem solved, no more "clickers". Not saying this will be everyone's "fix" but maybe it'll help someone.

 

[Mikecr]

Proper bolt timing would help for sure, but it doesn't really address so much need for it.
I believe most guns are built with excess clearance near webs, and weak breech support. This, leading to high web expansion to begin with.
Get ahead of that and limit load pressure to SAAMI max, and you'll mitigate extraction issues. You will never even need to size case bodies.
Of course the trick in 'getting ahead' of it, means building the action for this,, for the specific cartridge, and filling out your reamer print from NEW brass dimensions.
True custom