Supported Chamber???

Upjohn · July 12, 2000, 12:38 PM

I have heard people remark that certain makes or calibers of certain guns do not have a supported chamber.

Will someone please tell me what a SUPPORTED or UNSUPORTED chamber means?
Thanks

Chris McDermott · July 12, 2000, 01:52 PM

A fully supported chamber means that the brass cartridge case touches the chamber walls from the mouth to the extraction groove all aroung the case. An unsupported chamber has part of the feed ramp extending into this area, so that the brass case isn't touching the chamber. This causes the brass case to expand into this gap when the pistol is fired; producing a "bulge" in the brass case.
As reloading dies need some degree of an opening taper to work smoothly, especially in a progressive press, they cannot totally remove this bulge at the bottom of the case. This is why Glock says not to reload cases fired in a Glock, because they typically have unsuported chambers in their guns. I think Glock now makes a couple of models that do use a fully supported chamber; and some of the aftermarket barrels for Glocks have fully supported chambers.

July 12, 2000, 03:10 PM

Now I've never heard of Glock saying not to reload ammo shot in a Glock. I do know they say to not shoot reloads through a Glock, but that is just a CYA measure. I have reloaded many, many 9mm from my Glock with absolutly no problem. I know people who reload the .45 and 10mm with Glocks. The 40 *&* may be different because of the high pressures. However with .45, 9mm, and 10mm there is no problem. I do not have experience with reloading .357 sig ammo.

Clark · July 13, 2000, 12:03 AM

Good case support [to the web]

Patriot 45acp
Para Ordanance P14 45acp
Star Firestar 9mm
CZ52 9mm
CZ52 7.62x25
Berretta 1934 .380
Tokarev 9mm
Tokarev 7.62x25

Bad case support

Colt 1911 45acp
Glock 20 10mm
Glock 22 40sw
Glock 19 9mm
Kel-Tek P11 9mm
Kel-Tek P32
Para Ordanance P10 45acp

David Berkowitz · July 13, 2000, 12:48 AM

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Clark:
Bad case support

Colt 1911 45acp
Glock 20 10mm
Glock 22 40sw
Glock 19 9mm
Kel-Tek P11 9mm
Kel-Tek P32
Para Ordanance P10 45acp[/B][/quote]

I believe the G19 is fine, but you should add the G23 nad G27 to your list.

Rick Solomon · July 13, 2000, 11:27 AM

For a good review on Glocks in this area, go to
http://www.ugw.org

and go to the kB! page

Clark · July 13, 2000, 10:12 PM

I am measuring the Glock 19 as having .190" of case support and the 9mm web is .160" thick for .030" of unsupported case.

A $90 Tokerav has support passed the web! Why can't a Glock 19?

July 12, 2000, 12:38 PM	#1
Upjohn Member Join Date: June 13, 2000 Posts: 17	I have heard people remark that certain makes or calibers of certain guns do not have a supported chamber. Will someone please tell me what a SUPPORTED or UNSUPORTED chamber means? Thanks

July 12, 2000, 01:52 PM	#2
Chris McDermott Senior Member Join Date: March 30, 2000 Posts: 245	A fully supported chamber means that the brass cartridge case touches the chamber walls from the mouth to the extraction groove all aroung the case. An unsupported chamber has part of the feed ramp extending into this area, so that the brass case isn't touching the chamber. This causes the brass case to expand into this gap when the pistol is fired; producing a "bulge" in the brass case. As reloading dies need some degree of an opening taper to work smoothly, especially in a progressive press, they cannot totally remove this bulge at the bottom of the case. This is why Glock says not to reload cases fired in a Glock, because they typically have unsuported chambers in their guns. I think Glock now makes a couple of models that do use a fully supported chamber; and some of the aftermarket barrels for Glocks have fully supported chambers.

July 12, 2000, 03:10 PM	#3
KilgorII Guest Posts: n/a	Now I've never heard of Glock saying not to reload ammo shot in a Glock. I do know they say to not shoot reloads through a Glock, but that is just a CYA measure. I have reloaded many, many 9mm from my Glock with absolutly no problem. I know people who reload the .45 and 10mm with Glocks. The 40 & may be different because of the high pressures. However with .45, 9mm, and 10mm there is no problem. I do not have experience with reloading .357 sig ammo.

July 13, 2000, 12:03 AM	#4
Clark Senior Member Join Date: December 4, 1999 Location: WA, the ever blue state Posts: 1,980	Good case support [to the web] Patriot 45acp Para Ordanance P14 45acp Star Firestar 9mm CZ52 9mm CZ52 7.62x25 Berretta 1934 .380 Tokarev 9mm Tokarev 7.62x25 Bad case support Colt 1911 45acp Glock 20 10mm Glock 22 40sw Glock 19 9mm Kel-Tek P11 9mm Kel-Tek P32 Para Ordanance P10 45acp

July 13, 2000, 12:48 AM	#5
David Berkowitz Senior Member Join Date: November 10, 1999 Location: Yucaipa, CA USA Posts: 214	<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Clark: Bad case support Colt 1911 45acp Glock 20 10mm Glock 22 40sw Glock 19 9mm Kel-Tek P11 9mm Kel-Tek P32 Para Ordanance P10 45acp[/B][/quote] I believe the G19 is fine, but you should add the G23 nad G27 to your list.

July 13, 2000, 11:27 AM	#6
Rick Solomon Member Join Date: June 23, 2000 Location: Jackson, MS Posts: 43	For a good review on Glocks in this area, go to http://www.ugw.org and go to the kB! page

July 13, 2000, 10:12 PM	#7
Clark Senior Member Join Date: December 4, 1999 Location: WA, the ever blue state Posts: 1,980	I am measuring the Glock 19 as having .190" of case support and the 9mm web is .160" thick for .030" of unsupported case. A $90 Tokerav has support passed the web! Why can't a Glock 19?