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View Full Version : How tight of a chamber/headspace is too tight?



n10sivern
03-30-2013, 11:19 PM
Built my first savage recently in 6.5x55. I tightened the barrel down until it hit the go gauge. Put a piece of tape on the back of the go gauge to add 0.002" to make my no go gauge. I went and shot the other day for the first time. Tonight, I check my fired lapua brass against some new lapua brass using my hornady case/headspace gauges. They are the same. Should I expect some stretching? If so, is my chamber too tight to allow the brass to stretch? If it doesn't stretch and it is supposed to, will this cause exceedingly high pressures? There were no signs of high pressure on the cases.

kelbro
03-31-2013, 12:17 AM
You have nailed it on the first attempt. Good job. Brass that doesn't stretch lasts a looooong time.

mnbogboy2
03-31-2013, 12:21 AM
I set mine up the same way and yes the differences are small....If you FL, when chambering your next two or three firings you might feel some resistance when closing this is on the "tight" side...IF you are neck sizing the closings most likely will start to tighten up...That is time to bump back with your body sizer...If they are still snug with the body sizer adjusted all the way..Then most likely you are "tight"...In both cases only about .002 (simply re-headspace)....No worries about pressure work up loads as normal low to high...A tight chamber only adds to brass life but on the down side just a little bit of dust/dirt will cause the bolt not too close (really noticeable in the dusty winds out west)....

I bet yours will be just fine..
Good luck,
Randy

jonbearman
03-31-2013, 01:42 AM
The problem with tightening the barrel tight to the go gage is when you are tightening it against the gage the barrel will move slightly in the same direction taking up any normal slop and rendering the headspace too tight.I usually just back the barrel off a touch and hold it with my hand till its fairly tight and then check to see if when I open the bolt there is any pressure to move the handle.Then if it moves easy I add a piece of scotch tape and try and close.If there is any resistance you are perfect.If you cant bump it with the bump gage tight against the shell plate,take the shell plate out and lap it on some fine sand paper like on a flat surface and try to lap a couple thou off and try again with the bump die touching the shell plate and you should have about .220 thou bump which in my book is perfect.

stangfish
03-31-2013, 03:56 PM
The problem with tightening the barrel tight to the go gage is when you are tightening it against the gage the barrel will move slightly in the same direction taking up any normal slop and rendering the headspace too tight.

I mark my barrel nut and action with a pencil when the headspace is right. I also have the ability to hold the action and the barrel.
BTW as mantioned previously on anothr post; 10* of barrel rotation = .002 linier movement on the chamber.