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grouse
11-01-2009, 09:58 PM
I know this has been talked about time and time again, but just want a little assurance. I used a sized 300wsm brass to set the headspace. Closed with just a little extra pressure. I then put a small piece of masking tape on the brass and rechecked. Closed but with much more force. Am I close?

Armed in Utah
11-01-2009, 10:39 PM
Sounds like you're there to me.....

:D

grouse
11-02-2009, 12:53 PM
Thanks. Is maskint tape too thick?

ellobo
11-03-2009, 02:28 AM
The masking tape is probably to thick. Most guys use cellophane tape like 3M makes.

El Lobo

grouse
11-03-2009, 10:38 AM
So it should close with firm pressure with the cellophane
The resized brass closes in my other action with much more difficulty. It wasn't shot in that action is that normal?

twarren
11-03-2009, 10:48 AM
Your brass should be shot in the same action. The paper should be 2 thousandths thick for checking closing.

EFBell
11-03-2009, 10:50 AM
Brass shot in my factory chambered 300 WSM (Savage) will not chamber in my friends A-Bolt. Should not be a problem as long as you dont take the wrong ammo hunting with you. It would suck to get out in the field and find that your rounds wont chamber.

BillPa
11-03-2009, 10:59 AM
Thanks. Is maskint tape too thick?


Yes, use Scotch "transparent", .002x". I forget what other tapes measure.

My 280 Rem GO ( purposely made to 2.100 instead of 2.099)
http://i44.tinypic.com/2iw63x4.jpg

The same gage with a single layer of transparent tape.
http://i39.tinypic.com/2jczvac.jpg

A fired piece of brass from the chamber setup with the bare and shimmed gage.
http://i41.tinypic.com/2e1yrfn.jpg

The same case FL sized with a .002" bump. 2.099" is the SAAMI minimum chamber spec for the 280 Remington.
http://i40.tinypic.com/295x0eq.jpg

Standard gage spec for the 280 rem is 2.099 (Go) and 2.105" ( No Go), .006" tolerance.

Remember, a GO gage is used to set the chamber "equal to or greater than" and the No GO "Less than". If the bolt won't close on the No Go the chamber length must be something less than the gage length. If it closes on the GO, its something equal to greater than the gage length. The difference is the actual chamber length be it .003" for some cartridges oras much as .006 for others.


Closed with just a little extra pressure. I then put a small piece of masking tape on the brass and rechecked. Closed but with much more force.

Actually, when setting-checking headspace the bolt should close on the GO, but not the NO GO WITH NORMAL PRESSURE! Fact is, when its out of room...its out of room and all you may have accomplished was creating something shorter. Sizing the might be the next problem you run into, your FL die may be short enough to bump the shoulders enough.

If you want to see the correct method using gages (brass) , watch Gordy Gritters checking headspace , 1:30 to 2:20.

http://www.youtube.com/watch?v=KICBv-0U87Y&feature=related

Bill

grouse
11-03-2009, 08:42 PM
just decided to order the gauges and do it right. thanks

tammons
11-03-2009, 09:36 PM
Good idea.

grouse
11-03-2009, 11:37 PM
BillPa Thanks for the great info!!!

grouse
11-08-2009, 01:05 AM
I got the head space gauges for the wsm and got this gun headspaced properly. Just out of curiosity I put the gauges in my factory 300 wsm that I have been shooting for 5 years with no problems. There have been No modifications at all to this gun. The bolt closed on the go and the NO GO gauge with no trouble at all. Makes me wonder about the tolerances of needed for head space.

okie2
11-10-2009, 03:13 AM
if you sized your brass then used it for a go guage all you did is set it to what your die is set at and that is fine if you only load for that one rifle.
every one worries about head space too much.
read the test that P O ackly did with the barrel unsrewed one full turn.
As long as your die and the chamber head space are the same there is nothing to worry about no matter what length it is