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View Full Version : Best way to measure Locking Shoulder ?


Bolt2Bounce
April 16, 2008, 20:37
I have a embel receiver and kit which needs a smaller Locking shoulder so it will headspace. the bolt will not close, it is like field gauge, short with the go guage, but I don't know the best way to measure distance so I can order the correct smaller dia shoulder the first time around... I tried swapping L1A1 bolt but that bolt was even bigger... B2B

Mosin Guy
April 16, 2008, 20:47
http://www.falfiles.com/forums/showthread.php?s=&threadid=119640

Bolt2Bounce
April 17, 2008, 00:22
Thanks M guy that is/ was a very well put together tutorial... I guess I'll have to get some pin gauges or just guess at order a a few thousands smaller. My LS is .262 so I'll 260 may be the ticket... B2B

juanmurmylo
April 25, 2009, 17:29
How can you know you wont blow up your rifle without the proper tools?

I have just finished my first FAL made piece by piece. The last one was the loking shoulder. I put it in place and the B/C seem to close perfectly. I only have to do a small presure to make it close with the ejector in place.

I´ve been shooting with FALs for many years now and this one seems it will shoot with no problems. Is there any "field" way to know the B/C closes correctly without the Go / No GO?

Thanks

Argy/Para/Carabine w/DSA Heavy duty Mount and DSA metric PARA Carrier.

MAINER
April 26, 2009, 12:14
There is NO good way without the proper headspace gagues.

You can use a Nato spec cartridge with the firing pin and extractor removed. Place a layer of scotch or electrical tape on the base and try chambering the cartridge. Add tape untill the cartridge won't chamber, then remove the tape and measure all the layers. If you have more than .003" of tape, you should get headspace checked properly. If more than .006" of tape, stop shooting and get the thing fixed.

There is an old method of placing a small ball of modeling clay between the bolt and cartridge base, then carefully chambering the round. After removing the compressed clay disk, it could be measured like a gauge to determine headspace. I tried this once and thought it was one of my dumber moments and ordered 308 gauges from Brownell's.
There is a stuff called "Plasti-gauge" ? found at Auto stores that would likely work better.