grandpabear

I'm still new to this reloading. I've got the 9mm figured out and now it's time for my .40 s/w. What is all this I've read about the unsupported chamber stuff? Seems to me that my SR40 has a supported chamber. Does it? Can someone explain this and do you have any advice for .40 reloading. I have lots of data. I plan on starting with 4.2 grains of titegroup under a 180 gr. Hornady XTP.

Breadman03

Hey Grandpa!

I can't say I have tons of experience reloading, but the .40 is no more dangerous than any other caliber. Start low and gradually work up your load, inspecting each piece of brass for signs of being over pressure. For Glocks, one of the telltale signs is the Glocksmile where the brass begins to bulge into the unsupported area of the chamber, which is where the feed ramp protrudes slightly into the chamber.

I have loaded up about 300 .40 rounds for my G35 with no issues using Unique. I'm not trying to make nuclear loads, just tuning for point of impact and consistency.

leroy

Gramps:

Dont worry about it. We load 6.5 grains of Unique and 180 grain jhps for our Glock 27. That is basically the original old 10 mm "lite" load @ about 980 fps (...we havent chronographed our load yet....). No sign of bulged cases.

As others have said, pay attention to reliable loading manuals (.... hornady, speer, lyman, manufacturers data, etc. You get the idea...). I think the old "glock smile" thing is kinda like the mythical "wild bodenius". I've heard of 'em; i just aint seen one.

All this from a guy who has seen cases rupture (...old 38 super...) in a colt 1911. It did have a support problem plus an operator induced hot load problem. Several ruptured. No one hurt (...thankfully...). No damage to the colt 1911. That wuz a long time ago.

PS -- The way to check on case support is to take the barrel out of your pistol, drop in a round, and look for any sign of brass (...typically at the bottom of the chamber where the round feeds from the magazine up into the chamber...). If ya see brass once the round is chambered; that is an "unsupported area".

Hope this helps
leroy

bwinters

Most colt 1911 and similar until para ordnance had unsupported chambers and except for 38 super overloaded there were seldom problems.

bhefley59

Grandpabear I have been reloading 40 cal for years and it's no diff than 9mm. I also shoot a SR40 and have reloaded 10,000 + 40 cal. I have loaded 180fp @ 4.2 gr titegroup good load works well in mine. The SR40 has a fully supported barrel.

A suggestion get you a lee bulge buster and factory crimp, or another brand . The 40 will get a bulge around the base of the brass the resizing die don't reach. When I tumble my brass I use cheap white rice with a cap full of liquid car wax, run about 7 - 8 hrs. This makes the brass look new and slick enough you don't need case lube. I know, you don't need lube if you use carbide dies but this helps, less wear and tear on your dies and press.

Good luck !

Nick0410

Known as the "Glock smile". The SR series is supported, while "fully supported" isnt 100% fully, some are more than others. Its mostly where the feeding ramp starts, the SR9 series are supported more than most. In other guns, the feed ramp starts a little further in than the SRs where it has a good chamber around the round and the ramp on the end. I would think that .40 is just as dangerous as 9mm or pretty close. 9mm is pretty thick casing though so I've never had a split mouth, just loose primer pockets after many uses. Not sure how thick .40 is compared to it.

laidlerj

The SR40's chamber is fine for reloading - you need to compare it to a Glock. I've got a G27 (.40 S&W) and Glock 20 (10mm Auto) and their chambers are truly unsupported (not to mention being oversived). I've got a couple of other .40 S&W pistols (Beretta 96 and Springfield XDm) and their chambers are more normal - I don't even need to use the "DeGlockinator" (Redding G-Rx) on cases fired from those pistols.

If you've been reloading for the 9mm, you already know about putting a good taper crimp to keep the action from pushing the bullet deeper into the case (REALLY jacking up the pressure!), so reloading the .40 S&W it shouldn't be any different. I've seen recommendations to avoid 200 grain bullets in the .40 S&W (it can bulge the case and hinder chambering), but the 180 grain bullets work fine, although the performance of the cartridge is better (in my experience) with bullets of 165 grains and lighter.

Enjoy!

Jim

Timberbeast

I have a 40 Beretta and load lots...I usually load brass just once in 40, otherwise I get the life out of all other brass. I buy brass on gunbroker and it's usually cheap.

TMD

Some internet myths just wont die. Reload it like any other straight walled pistol cartridge and stay within SAMMI specs.
FWIW I've been using the same bucket of .40 range brass countless times in my Glock G35 with no buldge issues or KaBooms.

grandpabear

Thanks everyone! Sounds like I need a bulge buster just for peace of mind. I actually did a search after I posted and found lots of info. I trust all your experience and knowledge. Some say I read too much but I'm gonna keep reading.

Darkker

Folks have you on the correct path here.

The "un-supported" issue comes down to TYPE of action.
Anyone using the modified-browning, or swinging-link type action has an un-supported chamber. The discussion becomes HOW un-supported, and WHAT your pressures REALLY are.

Regardless of how "un-supported" the chamber is, there is no ammo that is within SAAMI spec, that will have an issue.

Remember that a load that is listed in a manual: Will have been loaded under standard temp. pressure, humidity levels. Are you loading under those conditions? They also deal with a specific lot, thus burning rate of powder. You won't have that same lot/speed. So the pressures in the book, and the real world will be different.
When you take a less supported chamber, and load a full-house load without doing any work-up; that is when you find your brass smiling back at you.

marlin39a

SR40 does have a fully supported chamber. I shoot my reloads with no fear. Your 180 XTP and 4.2 is a starting load from Hodgdon, and will work well. Just keep the OAL at 1.125 and taper crimp.