The polymer coating increases the pressure on bolt,
The "slipreness" of the cases means reducing the load since what holds the case in the chamber on a bolt action is the friction between the chamber wall and the brass. The bolt just helps a little to hold the round. So with the polymer you get flatten heads and primers, etc.
I put them through the tumbler once ... no effect. Steel wool works but what a pain.
It will take allot more then tumbling to remove. Reloading? tested to more then 10 reloading and most of it is intact.
Still not sure why you want to remove it. Yes brass expands during fireing to the chamber. But all it does is creat a gas seal. In a bolt action rifle brass expansion has hardly anything to do with keeping the round in the chamber.
" since what holds the case in the chamber on a bolt action is the friction between the chamber wall and the brass"
I have 9 locking lugs on my Weatherby 378mag. according to your hypothesis I don't need them.
Leave the coating alone and don't worry about it. If you are still concerned about the coating you might want to think about all the coated military brass out there made for bolt actions.
do it only with a known ok, reduced, load... than compare the results.
Rounds with no case taper and other cases, to a large degree, depend on the case to chamber friction. Do the research or the math (friction tables and surface area) and find out for yourself if its a question in your mind... dont rely on what I or another might believe.
My current question is "does anybody know an easy why to remove the coating".
Varmint Al has done the Finite Element on this and the brass really holds very little of the axial force. Think about it, stick a cartridge case in the reloader die and how hard is it really to pull the case head completely off. Particularly one of that small diameter.
The burning question is really once it's off how go you get it back on.
Are you asking this because you saw it in another forum ? The only reason I've ever heard of removing the coating is to allow more friction in a semi auto, as it improves accuracy,but, that info was from a Marine Core Sniper I know who was shooting a semi out to several hundred yards ! In a bolt action ? I don't see how the extra effort would afford any better of a shot?
Try a product called "Klean Strip- Premium Stripper" it can be purchased at any Lowes. It is designed to remove epoxy, polyurathane,glues, varnish/shellac. This stuff is hard core. I used it and the warnings on back need to be followed. My warning:
Do not get it on all or most plastics. It will disolve them!!!!
Memory is a funny thing. Mine keeps telling me that I read a post some where that said a fellow had used citric acid to clean his 5.7 brass, and that it had stripped off the coating, so he was washing his brass in a simple green solution.
I use citric acid for cleaning conventional brass cases and it works well for that application. I have never tried it on 5.7 brass, however.
If you have a glass of Kool-ade handy, drop one in and see what happens.