Barrel/Chamber Support

[EdMc]

.....or lack thereof. I have a Glock 20SF and have seen many comments about lack of support in Glock 10mm chambers. In looking at the barrel the chamber surrounds the casing except at the lower area where the ramp blends into the chamber. Or, is the criticism of the chamber sizing? Using pin gages the chamber tapers 0.436" down to 0.425" with the depth being 1.260. Hey, I promised dumb questions when I joined.

[sqlbullet]

Serious Glock guys will chime in I am sure.

But in general in more recent generations of Glock (Gen 3 on I think) have better chamber support for high pressure rounds.

[DM1906]

.....or lack thereof. I have a Glock 20SF and have seen many comments about lack of support in Glock 10mm chambers. In looking at the barrel the chamber surrounds the casing except at the lower area where the ramp blends into the chamber. Or, is the criticism of the chamber sizing? Using pin gages the chamber tapers 0.436" down to 0.425" with the depth being 1.260. Hey, I promised dumb questions when I joined.

[bold]
That's the key area we most often refer to when discussing "chamber support".  This is the part of the case that will blow out, if it does in almost every case.   Most aftermarket barrels will support more of this area, and some will enclose the entire case web area.  The trade-off is a tighter feed area, which can result in less than ideal feed characteristics, although FTF's due to this are extremely rare in normal situations.

OEM Glock barrel chambers are very generous (loose), in comparison to most AM barrels.  This "feature" lends to Glock's remarkable reliability, in almost any condition a shooter may encounter.  The trade-offs for the generous chamber are brass condition after firing (may be excessively expanded, bulged, or "smiled" with extreme pressures), less consistent firing/pressure characteristics, and perhaps less consistent accuracy.  YMMV

[REDLINE]

Yep.  What DM1906 said.

That 6 o'clock position of the Glock barrel chamber where case head (and just above) is relatively poor.  Colt Delt Elites are even worse.  But it is true the Glock 10mms have gotten better.  Not much, but better.

[sqlbullet]

Colt Delt Elites are even worse.

This really brings it to the source question.  Underwood, who runs as hot as anyone really should, does NOT call out the Glock as lacking enough head support for max loads.

[EdMc]

" Underwood, who runs as hot as anyone really should, does NOT call out the Glock"


I've noticed this too, in addition to a photo of a S&W barrel seen online that leaves  the same area above the ramp 'unsupported'. Never seen any criticism of the Smith.

As an aside I'm a little old for the 'fanboy' term....if anything, I'm more inclined towards Colts, the 20SF is the first Glock product I've owned.

[The_Shadow]

Here are the various barrels for my G-29...

Two Storm Lake barrels - Factory 10mm - Two Lone Wolf Dist.

Here are some of my S&W barrels...


The amount of exposed area is not the only thing involved, lock up and timing play a big roll in the situation as well.
I use the Wolff Gun Springs, non-captive two piece recoil rod with the 21 lb spring set in the G29 and the Wolff 22 recoil spring in the S&W 1006/1026/1046 and Wolff 21 lb spring in the 1066/1076/1086.  I handload my own to simular levels as Underwood and haven't had any "SMILED" brass yet!

[The_Shadow]

Here are some pictures of a Delta Elite barrel from a form\um member on another forum in my area...




Colt Double Eagle barrel

[EdMc]

Thanks gentlemen, ya'll never disappoint. Quite obvious from the photos that Colt does have the least support. Be interesting to see a Kimber 10mm barrel for comparison.

Shadow, with the changes in rod and springs on your G29 are you still using the stock 10mm barrel?

[The_Shadow]

Yes I carry it with the factory barrel!  The others are just for play and range work or hunting.
The 21 lb spring I feel helps with the dwell time and lock up.

[EdMc]

Thanks. I did find a photo of a Kimber 10 barrel with an internet search. I'm not sure how to post photos here, but it looks to be very well supported.

[REDLINE]

Colt Delt Elites are even worse.

This really brings it to the source question.  Underwood, who runs as hot as anyone really should, does NOT call out the Glock as lacking enough head support for max loads.

That's absolutely true, but still doesn't change that fact that the Glock barrel does leave a portion of the case completely unsupported, which to me is the main point that folks should be aware of, as it is a limitation in some respects whether we as individuals deem it "okay" or not.

[Vice]

Informative thread.  Might be considered for a sticky.

[EdMc]

I'd forgotten ...........here's the photo of  Kimber and Colt barrels. Colt on the right.

[The_Shadow]

Now the $64 question?  Is the Kimber barrel considered a Nowlin ramp cut? or Clark Ramp Cut?   
BTW I'm impressed with the Kimber's chamber support!  I wonder how it compares to the Fusion design?