.223 neck size only on a Semi? - Page 2

tangolima · April 25, 2017, 06:11 PM

0.01" > 0.004"

-TL

Sorry I was in a hurry.

Your head clearance is 0.004", which is quite good for a semi auto. 10 firings shouldn't be problem.

0.01" head clearance is too much. You are lucky to get a few firings out of it.

-TL

Metal god · April 25, 2017, 11:28 PM

No I'm sorry , i did not recognize you wrote .010 rather then .001 . So yes you're correct ten thousandths would be way to much head clearance .

Sorry for the misunderstanding.

Here are some cases that had somewhere between .008 to .010 head clearance I shot . The head separation/cracking happened on the third firing .

tangolima · April 26, 2017, 12:49 AM

I just tried that myself, about the bullet movement. 168gr bullet on 8mm Mauser. Rifle is Hakim. One round in magazine (minimum friction). No measurable change in COAL.

-TL

Gunplummer · April 26, 2017, 07:23 PM

Uncle Nick and I rarely agree on anything, but this time I do. Out of thousands of M16 and M16A-1 rifles I worked on, only one fired out of battery. The operator took a lot of brass in the arm and face. Supposedly these rifles cannot fire out of battery, but this one did. The only conclusion we could come to was that it was so dirty it could not feed the cartridge far enough to lock up.

When it comes to an autoloader still having pressure when it unlocks, yes it can. That is what timing is all about. We used to bump up the bleeder valve on the 240 coax guns so far that flame came out of the bottom when it extracted. Anybody that has converted a gas operated autoloader to a different caliber can tell you how hard it is to balance it out.

April 25, 2017, 06:11 PM	#26
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,854	0.01" > 0.004" -TL Sorry I was in a hurry. Your head clearance is 0.004", which is quite good for a semi auto. 10 firings shouldn't be problem. 0.01" head clearance is too much. You are lucky to get a few firings out of it. -TL Last edited by tangolima; April 25, 2017 at 08:14 PM.

April 25, 2017, 11:28 PM	#27
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	No I'm sorry , i did not recognize you wrote .010 rather then .001 . So yes you're correct ten thousandths would be way to much head clearance . Sorry for the misunderstanding. Here are some cases that had somewhere between .008 to .010 head clearance I shot . The head separation/cracking happened on the third firing . __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again . Last edited by Metal god; April 25, 2017 at 11:49 PM.

April 26, 2017, 12:49 AM	#28
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,854	I just tried that myself, about the bullet movement. 168gr bullet on 8mm Mauser. Rifle is Hakim. One round in magazine (minimum friction). No measurable change in COAL. -TL

April 26, 2017, 07:23 PM	#29
Gunplummer Senior Member Join Date: March 11, 2010 Location: South East Pa. Posts: 3,364	Uncle Nick and I rarely agree on anything, but this time I do. Out of thousands of M16 and M16A-1 rifles I worked on, only one fired out of battery. The operator took a lot of brass in the arm and face. Supposedly these rifles cannot fire out of battery, but this one did. The only conclusion we could come to was that it was so dirty it could not feed the cartridge far enough to lock up. When it comes to an autoloader still having pressure when it unlocks, yes it can. That is what timing is all about. We used to bump up the bleeder valve on the 240 coax guns so far that flame came out of the bottom when it extracted. Anybody that has converted a gas operated autoloader to a different caliber can tell you how hard it is to balance it out.