Any trick to opening AK boltface?

Prototype Services · June 20, 2011, 06:50

I need to open the boltface on a Romy bolt for 45acp. Any tricks to doing this, such as grinding a certain shape on the lathe tool etc?

Opinion please, would a 45acp need the fully encased boltface like the 7,62? Or can I step the bottom back flush with boltface so the round will slide up during feeding?

Slow · June 20, 2011, 07:45

i found these to be handy for that type of work, you can always grind some HSS to this profile (that how i used to do it) but i happened to obtain a couple of these carbide internal groove bits from a past job and they work great. i did not buy them from here but this was the first pic to google up.

http://www.internaltool.com/products....php?series=20

Prototype Services · June 20, 2011, 18:16

Thanks Slow, do you cut 90 degrees to the chuck bore? I was thinking of using a small boring bar and feeding parallel to the bore, or even reversing the chuck and using a V-shaped tool to cut. I haven't seen or done this gunsmithing step before, but know it is done.

My thoughts on cartridge feed are based on looking at the ramped barrels on my 1911s and the flat boltface on the slide.

mountainman · June 20, 2011, 19:53

make sure that the stem is concentric to your breechface. Cause if it isn't, thgen you have to ......

Prototype Services · June 20, 2011, 22:23

MM, of course I will check that first, but can't imagine it being an issue here. Once I weld it to the carrier it will have to float and self-align with the chamber.

Version-2 may get a new-made bolt/carrier machined from barstock. For now I am just doing a prototype and trying to 'only' modify original parts.

muttman · June 21, 2011, 03:59

look over on gunco. rino66 converted a boldt head to .45 with a good wright up. muttman

Prototype Services · June 21, 2011, 15:47

Thanks muttman, just spent several hours reading as much 45 stuff there as I could find. I think spec for the 45 is .473", and he used a .500" endmill in a vertical mill. I think I'll use the lathe and open mine to .473".
I hope mine will work as well as his build has, but I'm going about it differently.

June 20, 2011, 06:50	#1
Prototype Services Registered FALaholic #: 3935 Join Date: Aug 2001 Location: Gainesville Georgia 30501 Posts: 2,067	Any trick to opening AK boltface? I need to open the boltface on a Romy bolt for 45acp. Any tricks to doing this, such as grinding a certain shape on the lathe tool etc? Opinion please, would a 45acp need the fully encased boltface like the 7,62? Or can I step the bottom back flush with boltface so the round will slide up during feeding? __________________ ''Life's tough.....it's even tougher if you're stupid.'' ~ John Wayne

June 20, 2011, 07:45	#2
Slow Registered Bronze Contributor FALaholic #: 17330 Join Date: Apr 2005 Location: Houston, TX Posts: 1,653	i found these to be handy for that type of work, you can always grind some HSS to this profile (that how i used to do it) but i happened to obtain a couple of these carbide internal groove bits from a past job and they work great. i did not buy them from here but this was the first pic to google up. http://www.internaltool.com/products....php?series=20 __________________ Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it What’s the point in ever trying to be happy when the very pursuit of happiness is what makes you miserable. I'm trying to see things from your point of view, but i can't stick my head that far up my ass *"The earth swarms with people who are not worth talking to"* -Voltaire "If you mix fat and lies, you get Bill, not soap. Throw in some stupid, and it turns to Vince." - ce

June 20, 2011, 18:16	#3
Prototype Services Registered FALaholic #: 3935 Join Date: Aug 2001 Location: Gainesville Georgia 30501 Posts: 2,067	Thanks Slow, do you cut 90 degrees to the chuck bore? I was thinking of using a small boring bar and feeding parallel to the bore, or even reversing the chuck and using a V-shaped tool to cut. I haven't seen or done this gunsmithing step before, but know it is done. My thoughts on cartridge feed are based on looking at the ramped barrels on my 1911s and the flat boltface on the slide. __________________ ''Life's tough.....it's even tougher if you're stupid.'' ~ John Wayne

June 20, 2011, 22:23	#5
Prototype Services Registered FALaholic #: 3935 Join Date: Aug 2001 Location: Gainesville Georgia 30501 Posts: 2,067	MM, of course I will check that first, but can't imagine it being an issue here. Once I weld it to the carrier it will have to float and self-align with the chamber. Version-2 may get a new-made bolt/carrier machined from barstock. For now I am just doing a prototype and trying to 'only' modify original parts. __________________ ''Life's tough.....it's even tougher if you're stupid.'' ~ John Wayne

June 21, 2011, 15:47	#7
Prototype Services Registered FALaholic #: 3935 Join Date: Aug 2001 Location: Gainesville Georgia 30501 Posts: 2,067	Thanks muttman, just spent several hours reading as much 45 stuff there as I could find. I think spec for the 45 is .473", and he used a .500" endmill in a vertical mill. I think I'll use the lathe and open mine to .473". I hope mine will work as well as his build has, but I'm going about it differently. __________________ ''Life's tough.....it's even tougher if you're stupid.'' ~ John Wayne

June 20, 2011, 19:53	#4
mountainman Registered FALaholic #: 14702 Join Date: Jun 2004 Location: Deltona FL Posts: 3,192	make sure that the stem is concentric to your breechface. Cause if it isn't, thgen you have to ......

June 21, 2011, 03:59	#6
muttman Registered FALaholic #: 19106 Join Date: Jan 2006 Location: west,TN Posts: 311	look over on gunco. rino66 converted a boldt head to .45 with a good wright up. muttman

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