Reloading 40 s&w how much bulge is too much?

duck32man

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I have a question regarding the infamous bulge. After sizing my brass in RCBS dies I am averaging .421 with a bulge of .422. Is this enough to warrant a bulge buster? I shoot these through my Glocks and my Shield. So far I have had no issues with chambering in either. But man there is so much out there about bulge and pressures and exploding guns.
 
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Got any pics of these cases? I toss any bulged brass I pick up and I won't own a weapon that doesn't fully support the cartrige. IMO If you're in doubt toss them to avoid any safety issues.

Now that I have thought about it and have re-read your post. Most resizing dies don't quite get to the very base of the case and it sounds to me like you're measuring the case mouth and the very base of case? I'm actually doing a huge run of 40's right now so let me do a few caliper checks. Ok... your measurments are normal after resizing. You'll know the cases to toss as the bulge looks like a guppy fishes belly.
 
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I use a chamber gauge from Dillon to check them all....if they drop in easily they are good to go.

My Dillon dies seem to size them far enough down that even with a noticeable bulge it is not an issue for me.

Randy
 
Not sure if you can see it well enough.
 

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Yes, I measured mouth vs base. With this slight variation it doesn't represent any case weakening then?

Got any pics of these cases? I toss any bulged brass I pick up and I won't own a weapon that doesn't fully support the cartrige. IMO If you're in doubt toss them to avoid any safety issues.

Now that I have thought about it and have re-read your post. Most resizing dies don't quite get to the very base of the case and it sounds to me like you're measuring the case mouth and the very base of case? I'm actually doing a huge run of 40's right now so let me do a few caliper checks. Ok... your measurments are normal after resizing. You'll know the cases to toss as the bulge looks like a guppy fishes belly.
 
The problem is not so much one bulge, but repeated reloading of brass that is being bulged. It eventually gets weak in that area and can cause a problem. If you are not loading Max loads then you should not have a big problem.

If you spend the money and buy a aftermarket barrel like Lone Wolf for the Glock then you have no worries and can shoot lead also,

My 9mm Shield bulged 124 gr +P ammo badly but did not bulge regular non +P.

It's not a range gun so the bulged brass is going into the recycle bin.

These are pretty severe for a "Fully Supported" chamber, it's just a loose chamber so it will feed anything.

Post #6
http://smith-wessonforum.com/smith-...s-have-unsupported-chamber.html#post137435636
 
I have to say this forum and you all are a great resource! Thanks for the replies.
 
They really didn't design the .40 with reloading in mind, did they???

I don't think you can say that. The simple truth is that when you reduce the size of a semi automatic you end up making sacrifices. Such as cutting the feed ramp a bit deeper into the chamber in order to insure reliable feeding.

If you want a 40 caliber that won't require a feed ramp cut into the chamber all you have to do is take the overall length of the cartridge and multiply it by 3.5 to determine the barrel length. That will allow a long enough action length for the slide that it won't be necessary to cut into the chamber to insure reliable feeding.
 
If you read Lee's website they warn that once the brass is weakened (thinned and work hardened) by the bulge that passing it through the bulge buster does not re-thicken the brass and that spot will always be weak and prone to blow out if it ends up over the unsupported area again.
Slow powders and less than max loads should be the rule of thumb when reloading .40s&w.
 
It's not just 40 SW Glocks. Browning HP in 40SW do it also.

But that is what also make them so reliable. The more open or lose chamber allows them to feed any ammo easily.

As I just found out the S&W Shield 9mm does it on high powered loads. Do not know about the 40 SW yet.

Original GI 1911's had very few problems as they were loose fitting. The new super tight ones have more jams, stovepipes and other finicky problems.
 
Maybe your 1911's do...

Dropsy yours in the dirt or mud and see how it "runs":)

And before you say, I don't drop it, it was just sort of kinda and analogy for loose chambers and why Glocks work under extreme conditions . No I do not like Glocks
 
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HOLD the BUS !!

Will you look at that brass in the #5 post................
Mercy...........

I have never ever seen a case that bad, before.

As for the 1st post, that little ring at the bottom of the case
is due to the Collet preventing the die to go any farther down
on the shell. This is normal...........
Some that load for 9mm don't even go that far down for certain
reasons, just can't remember why, right now.

You are fine.......... keep on loading.
 
HOLD the BUS !!

Will you look at that brass in the #5 post................
Mercy...........

I have never ever seen a case that bad, before.

As for the 1st post, that little ring at the bottom of the case
is due to the Collet preventing the die to go any farther down
on the shell. This is normal...........
Some that load for 9mm don't even go that far down for certain
reasons, just can't remember why, right now.

You are fine.......... keep on loading.

Yeah, I've cooked up some heavy duty Longshot loads in my M&P and didn't see anything like that. I don't know what those cases were shot in but dude's about to have a case head separation blow out soon if he doesn't back off the fast burning powder.... :eek:


Dropsy yours in the dirt or mud and see how it "runs":)

And before you say, I don't drop it, it was just sort of kinda and analogy for loose chambers and why Glocks work under extreme conditions . No I do not like Glocks

I don't.... Oh.... :p

Joking aside, I think Colt is doing really well with the 1991A1 being loose enough to run gunked up. While it's no Ed Brown with that oiled glass on glass slide fit it's not a GI maraca either. I have had mine running filthy in the dirt with Unique flammable dirt all over the insides to the point that loading mags was pushing crud into the action. And I say filthy with dirt only because it was a dry windy day and dirt devils were giving all of us a good sand bath that day. But have I intentionally "glock tested" it? Ummmm... No.
 
I am getting ready to load a lot of 40 S&W ammunition. I will Bulge Buster every round. This ammunition will be shot in either a 610 or 310 Night Guard. Revolvers are a lot more picky about the bulge.

I went through a large amount of brass a while back. I found WAY more bulged brass in the stuff I had on hand from 20 years ago than in the fresh stuff.

My advice is: If you reload Range Brass run it through a Bulge Buster. If you are reloading only brass shot in your 40 it is not as big a deal.

Bob
 
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