The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Thread Tools Search this Thread
Old March 9, 2000, 07:56 PM   #1
SW 586
Senior Member
Join Date: March 9, 2000
Posts: 269
At present I reload only for 38/357. I would like to start reloading for the 40. I'm sure most of you are familiar with the warning in various manuals (Hodgdon in particular) stating that the barrel must fully support the cartridge in the chamber to prevent bulged or ruptured cases. My handgun is a S&W Model 410. How can I tell, or can anybody tell me, whether my gun meets this criteria. I didn't know whether to post this in this forum or the handgun forum, sorry.
SW 586 is offline  
Old March 9, 2000, 09:42 PM   #2
Chad Young
Senior Member
Join Date: September 20, 1999
Location: Gainesville, FL
Posts: 601
The most commonly encountered guns with portions of the chamber unsupported is the Glock pistol. In order to promote proper feeding, the feed ramp is inletted such that a very small portion of the case is not fully supported. This is a large part of the reason Glock does not recommend reloads!

An easy way to see if your chamber is fully supported is to pull out the barrel and drop in a round. If the case is supported all the way around at the web, no problem. If I am not mistaken, yours should be fine.

Oh, for fun medium-power loads easy on the brass, try Winchester Super Field. I like 6.4 grains under a 165grain FMJ.
Chad Young is offline  
Old March 9, 2000, 10:19 PM   #3
SW 586
Senior Member
Join Date: March 9, 2000
Posts: 269
I feel like an idiot for not doing that already. Sure enough, the case is fully encircled by the chamber with no inletting. Looks like I'm good to go. I'll try your load suggestion. Thanks for responding.
SW 586 is offline  
Old March 11, 2000, 02:34 AM   #4
Join Date: March 3, 2000
Posts: 38
funny so is my G23...hmmm how can that be, there suppose to be a big gap at 6:00 oclock, well maybe its overrrrr exagerated.

Hey maybe the 40 is pushed to the outer limits and any mistakes and boom, unlike 45, 10mm. (9 is cool cause it has lots of metal thickness at the chamber. Yep, I think this is it! Plastic is fine, its simple, it works! Ask a million cops!

Dont trash my Glock!
Pooch is offline  
Old March 13, 2000, 02:40 PM   #5
Senior Member
Join Date: January 29, 2000
Posts: 275
This is from the Steyer M40 review on

Some manufacturers of 9mm pistols simply rebarrelled, modified the breechface
and put in a stiffer recoil spring to develop their initial .40 S&W pistols.
Since the .40/10mm bullet is bigger than a 9mm, the only way to get the .40 to
feed reliably was to create an intrusive feed ramp, and possibly an oversized
chamber to match. Thus the .40 S&W "Unsupported Chamber" was born. This was a
quick and dirty fix by some manufacturers to get to market fast.
Other manufacturers either started from scratch or went through the added
expense to redesign their 9's to safely handle the .40 with a well-supported
chamber that still feeds reliably. These types of .40 pistols are therefore
safer to use, whether you shoot factory ammo or reloaded ammo.
If you want to find out if your .40 has a well supported chamber, then do
this: Measure the diameter of the lower, most expanded part of some fired
brass. After the first measurement, rotate the brass slightly and measure it
again because the brass sometimes measures greater from a certain angle
because of the 6-o'clock chamber opening affect. If your brass measures .431
or greater, then your chamber is entering into unsupported territory. Also,
put a round into the barrel and look at the 6-o'clock position of the chamber
opening. If the thin part of the brass wall is exposed, or too much brass is
exposed, you have an unsupported chamber. "Both" of these measurements are
important to determine if your chamber is well supported or not. The greatest
brass expansion occurs when shooting full power loads.
The diameter of fully supported chanber brass usually measures around .427 -.429 for full
power loads. The Glock .40 can expand brass as much as .431 .433, which is a
huge difference.
Generally speaking, ammo and gun companies don't care about reloading safety
and case life. Some of the newer reloading manuals have strong warnings about
reloading for pistols with unsupported chambers, especially concerning high-
pressure cartridges.
One positive side effect of Glock's famous unsupported chamber and their
marketing omnipresence, is that some ammo companies have beefed up their .40
S&W brass so it has a better chance of surviving when fired in a Glock


A "Miss" is the ultimate overpenetration!
You can never be too rich, too skinny, or too well armed!
Banzai is offline  

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 12:31 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2018 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent:
Contact Us
Page generated in 0.06732 seconds with 9 queries