Glock G40 chamber support

[Bambam]

Hello,
could please somebody of the Glock G40 owners make a foto of a round in the barrel, where the chamber support is shown?

I own a Glock 20 gen. 3 and I ask me if the G40 has a better chamber support then my G20.

Many thanks

Wolfgang

[The_Shadow]

Wolfgang, I think the G-40's also share the exact same chamber cut as the G-20SF and 3rd & 4th gens.  The chamber is 0.4340" and case support is the same at the feed ramps.  My G-29 is also equal to the G-20SF I have...

The older G-20's Gen 2 did have way less chamber support than the newer Glocks.

[Bambam]

Thank you for the fast response.

It's too bad that the G40 has the same support...

Wolfgang

[The_Shadow]

I have run some of the hottest stuff in my G-20SF without issues but I also run a non captive recoil rod and 22 lbs spring.
No Smiles and cases will fill the 0.4340" chamber. 
The good thing is the G-40 will accept the aftermarket barrels, if you want more support then you may want to try Bar-Sto for their performance;
If you buy a MT (Match Target) Barrel, it will NEED to be fit by a gunsmith.
If you buy a SF (Semi Fit) Barrel, it may POSSIBLY NEED to be fit by a gunsmith.

https://www.barsto.com/category_main.cfm?ID=G40&cco=125

[Bambam]

Could you please explain the benefit of the non captive recoil rod?

Thanks for the link of the aftermarket barrel manufacture (I don`t know whether its available in germany, I have to look.)

Do the Bar-Sto barrels work reliable? Beside my normal rifle, I use me Glock 20 to trail wounded hogs...

[The_Shadow]

Not sure if they sell to your location, but there is an overseas barrel maker for Glock.
http://www.igbaustria.com/shop/product_info.php?language=en&info=p14_igb-gewindelauf-fuer-glock-9mm-pistole.html&

Here are some measurements I made between the Factory Captured recoil rod and springs and the non captive I use;

Glock 20Sf Factory spring test
It takes 5lb 3oz to start the slide to move from the locked position
Full retraction at 18lb 0oz at lock open

Glock 20SF spring test Wolff Gun Springs 22lb RSA installed
It takes 6lb 4oz to start the slide to move from the locked position
Full retraction at 22lb 9oz at lock open

22-Slightly over a pound difference 1lb 1oz to start the slide to move from the locked position
24-Slightly over a pound difference 2lb 3oz to start the slide to move from the locked position
22-Slightly over a 2 pound difference 2lb 9oz at lock open
24-Slightly over a 6 pound difference 6lb 1oz at lock open

[4949shooter]

Both f my stock Glocks have fired the hottest ammo out there (Underwood 155 grain XTP included) without any pressure signs whatsoever.

I have a later Gen 3 SF (2011) and a Gen 4.

[triggerman10]

The biggest problem I have with my 20 is splitting starline brass on the first firing. No smilies though.

[The_Shadow]

triggerman10, What powder are you using?

[Bambam]

The_Shadow, thanks for the link: I will contact the company...

[Dave84]

I've never had issues with the support in mine. Shot tons of Underwood and some DT to name the hottest loads. I have a 29 sf, a new Glock 40, and had 2005 gen 3 20. Stay away from stormlake for after market barrels. Thing was VERY picky.

[triggerman10]

triggerman10, What powder are you using?

Blue Dot

[my_old_glock]

The biggest problem I have with my 20 is splitting starline brass on the first firing. No smilies though.

My Starline brass also splits. I don't think they annealed it correctly.


.

[sqlbullet]

Must be lot specific.  I shoot lots of blue dot in almost exclusively starline brass and rarely have a neck split.  When I do it a case so old you can barely read the headstamp.

[Pablo]

Interesting. Frankly, I have been shooting some unpublish-ed/able    HOT batches (I have to get a chronograph!) with Starline and while perhaps brass life might suffer, I have seen zero, and I mean zero visible brass damage, and frankly nothing more than some primer flow that told me to back off. Case swelling is consistent throughout. I agree something might be wrong with that brass or it's seen ammonia or some heat/process it didn't much like.