Unsupported Chamber?

Sport45

New member
I have a friend who is thinking about reloading for his Beretta 96 (40 S&W). I though I'd let him buy the dies and start out with a press of mine. What I don't know is if the Beretta is considered to have a supported chamber or not. I suppose I could ask for the pistol, strip it and drop a cartridge in to see for myself but I really wouldn't know how much brass I should see. Any insight would be appreciated. If the Beretta doesn't have a supported chamber I will caution him that this is probably not one he wants to learn with.
 

918v

Moderator
Whether the gun has a supported or an unsupporte chamber should have no bearing on your reloading decisions. You should load mild, accurate loads to start and progress to full=power loads when you have mastered the art.
 
"Unsupported" is a relative thing. Most guns depend on the brass at some point to seal the chamber, so a bit of brass exposed near the rim doesn't mean much. You look at positive feed on a Mauser rifle bolt, for example, compared with a Remington bolt, and the whole bottom portion of the rim surround appears to be missing. The case head is just too thick for that to cause a problem within the normal range of pressures.

Your friend's gun, if designed for the .40 S&W, will offer enough support of the .40 S&W case to withstand .40 S&W pressures, whatever that required support is? You're only concern, therefore, is to stay within those limits.

The importance of distinguishing supported from unsupported case chambers arose in the 1911 because the integral ramp barrel became available and offers more complete case support than the original design. It therefore can tolerate loads a bit hotter than the orginal pressure limits without blowing out the side of a case. This matters particularly to those shooting .38 Supers and other lighter bullets and having to make "major" for IPSC matches. I am unaware of any supported/unsupported barrel options for your friend's gun, so I doubt there is a choice in pressure range available to him. He will just have to stay with SAMMI max loads.

The bottom line is, what 918V said. You should start reloads low and work up as with any other reloading. That applies to both supported and unsupported case chamberings alike. The only difference might be the starting loads could be slightly higher in a 1911 with an integral ramp barrel. If I owned one I wouldn't trust that and would use the same start loads I would for any .45 ACP.

Nick
 

Dave R

New member
My experience is, an unsupported chamber DOES affect how hot you can load.

I have two .380's. My P-3AT has a (relatively) unsupported chamber, and my PPK clone has a (relatively) well supported chamber.

When I was playing with defensive loads, I got near, but a few tenths under, the max in my Speer manual. Cases fired from the P-3AT showed a definite bulge in the unsupported area. Bad juju. Cases fired from the PPK came out looking pristine.

So I backed off the load a few more tenths, and everything's copacetic. If I had been firing from the PPK only, I would not have backed off.
 

MrApathy

New member
shouldnt be to bad with mild loads
40SWchmbr.jpg
 

Sport45

New member
Thanks for all the help. We'll definately start with the "start" loads and probably won't go up unless they don't cycle his pistol. I'll be looking over his shoulder the whole time. I'd load them for him, but he needs to learn this and I don't need the liability.

MrApathy,

I've seen those pictures before, but couldn't find them with a search. Where were they posted?
 

shooter_john

New member
I learned how to reload with .40 S&W for Glocks. I now have plenty of usable cases that have been fired 3 times, and I have yet to blow up a gun or see bulged cases. I use 8 grains of Blue Dot with a 165gr FMJ
 

newbloader

New member
Hello all I am knew to the sport of shooting and reloading and I was wondering what is a supported barrel and what is a unsupported barrel I have never heard of this and I am curious in what you all mean by this?? thank you for your time

Joey
 

918v

Moderator
Look in the above picture. HK USP has a fully supported barrel because the chamber covers all of the case head forward of the extractor cutout. The Glock does not because it leaves 1/16" of the case head exposed.
 
Lookig at the picture more closely, I notice the top pair (left and right) are unsupported, the next pair down are better supported, the next pair after that are the same or slightly better supported than the pair above them, then the bottom pair are both fully supported.

Nick
 

Rico567

New member
I have reloaded a lot of .40 S&W range pickups. I've seen a few bulged pieces of brass, but if the bulge can be seen, I discard that case. I have never seen a fired case I reloaded bulge. I reload a 165 gr. Rainier plated FP bullet, and the load develops 1050-1075 over the chronometer; not a maximum load, but no blooper, either. I have a friend who also reloads for .40, and he's never seen any of his bulge, either. We both shoot Glocks.

IMHO, the advice given earlier in this thread is completely sound. Reload only moderate, published loads and you'll have no trouble. I have several other opinions, from reading around on various forums:

1) I think that "pushing the envelope" in .40 is, as one poster so elegantly put it, "bad juju." If you're going to work up hotter loads than those published, do it a tenth grain at a time. This is particularly true for those loading fast powders such as Titegroup or Clays.

2) I think that 155-165 gr. is an ideal bullet weight for .40 S&W. A lot of factory ammo is loaded with 180 gr. bullets; while these factory loads are invariably safe, the 180 gr. bullet derives from loadings for the pappy of the .40, the 10mm, and, in my opinion, is a tad heavy. Attempts to hot up the heavier .401 bullets may be perilous; if you want a 10mm, buy a 10mm.
 
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