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DVC open and case head separations


TeedOff

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Tl;dr  what brass works best for 9mm major loads?

I'm a new DVC open shooter.  Loaded up some Montana gold 124s, autocomp, loaded to 1.160". Ran loads from 6.0 group to 7.2 gr.  No signs of over pressure...speed was good about 178 PF with the 7.2 gr load, so I loaded up a few hundred, ran about 100 thru the gun with no issues and headed to my first match with high expectations.  This is going to be fun!

First stage, first shot bang, then fails to chamber.  Tried another mag.  WTH?  Long story short, I had a case come apart.  It was one of those cases with a cannalure.  Yes, I found the case head and matched it up to the piece I knocked out of the chamber. So, I'm thinking ok just don't load any cannalured cases to major...no problem.

Today, I took out another batch of Ammo for a practice session...three more case head separations.  WTH!  Happened to notice all three are head stamped "ammoload". Ok, so now I sorted out all the cases with cannelures AND all the "ammoload" headstamps. 

Am I doing it wrong?  Are there any tips to prevent cases from blowing apart?  Are there any other head stamps I should avoid?

Thanks!

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Should have mentioned...I've been using random range pick up brass for several years without any issues in my Glock 34, sti Trojan 9mm, sti edge 9mm and MPX.  Probably around 20,000 rounds loaded in the last three years. 

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Ammoland, IMI, and FC are all "stepped" cases; the bottom part of the case (the end near the head) is thicker, then part way up it's machined thinner, causing a "step".  This is where it breaks.  They're fine with minor (like the Glock), but the pressures are much higher in Open.  You have a particularly "warm" load at 178 PF, and this stresses the case past what it can handle.  Suggest reducing your load to 171-172 and avoiding the stepped cases like the plague.  

Also, I'm finding that Blazer brass seems to be soft and doesn't hold 124 gr JHPs very well; in some rounds the bullet can be rotated just with your fingers or pressed into the case by hand.  Not using them any more, either. 

Edited by teros135
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1 hour ago, teros135 said:

Ammoland, IMI, and FC are all "stepped" cases; the bottom part of the case (the end near the head) is thicker, then part way up it's machined thinner, causing a "step".  This is where it breaks.  They're fine with minor (like the Glock), but the pressures are much higher in Open.  You have a particularly "warm" load at 178 PF, and this stresses the case past what it can handle.  Suggest reducing your load to 171-172 and avoiding the stepped cases like the plague.  

Also, I'm finding that Blazer brass seems to be soft and doesn't hold 124 gr JHPs very well; in some rounds the bullet can be rotated just with your fingers or pressed into the case by hand.  Not using them any more, either. 

I load FC and Blazer over and over in 9MAJOR?

And I have never found a ledge in FC.

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Just now, Sarge said:

I load FC and Blazer over and over in 9MAJOR?

And I have never found a ledge in FC.

Sorry, FM (Freedom Munitions). 

Out of the 20 or so 9 major rounds that had loose bullets, all but 3 were Blazer.  May be a difference in our loading rigs, but it's mostly Blazer here, which says something about them. 

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4 minutes ago, teros135 said:

Sorry, FM (Freedom Munitions). 

Out of the 20 or so 9 major rounds that had loose bullets, all but 3 were Blazer.  May be a difference in our loading rigs, but it's mostly Blazer here, which says something about them. 

Actually FC and Blazer are why I started using a Udie. Both plus some foreign stuff has thinner case walls. With a Dillon die I was able to push MG's in with my thumb pushing into the bench. MG's are slick and tend to be undersized in my experience. .3545 on one batch. Combine that with thin case walls and you can easily get in trouble real quick

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The 3 cases that cause this are Ammoload, FM and IMT. I have witnessed the case separation 4 times. I check all brass before cleaning, after cleaning and after case gauge to be 100% this junk does not make it to my mag. 

Regarding "loose" bullets, I found the same thing when I first started reloading 9 major. I got a Lee U die and that cured the problem.

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I'm going to have to give that a try.  Just came over to 9major, and with the short case and 1.165" OAL it's a bit more exacting than standard 9mm.

 Is it the EGW die we want, or the Lee?

Edited by teros135
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1 minute ago, teros135 said:

I'm going to have to give that a try.  Just came over to 9major, and with the short case and 1.165" OAL it's a bit more exacting than standard 9mm.

 Is it the EGW die we want, or the Lee?

They both work and cost about the same once you figure shipping. I THINK the EGW has a little more milled off the bottom to size lower.

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Cull out FM, IMT, and Ammoload which all have the step. These pieces of brass are very well known for being problematic. I won't even load them to minor. 

Second, and just my opinion, is I'm not big on Autocomp for major loads. It's a little on the quick side for my taste and I noticed it was rough on my gun, brass, and health which was confirmation of excessive peak pressures. 

So 178 pf with Autocomp in my own experience was no good on any level and I wouldn't recommend it. 178 pf is rough enough, but with Autocomp it's exponentially worse. 

Why anyone would shoot 178 pf today is beyond me. 

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Second note. It's likely you have a gun with a fairly loose chamber causing this much brass stress given the immediate rates of failure you're experiencing. I'd recommend keeping all your loads, whether Autocomp or not, to around 170 and implementing strict QC on your pick up range brass. 

And what was the head stamp on the very first brass failure you had?

Edited by theWacoKid
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On 11/7/2016 at 10:47 AM, theWacoKid said:

Second note. It's likely you have a gun with a fairly loose chamber causing this much brass stress given the immediate rates of failure you're experiencing. I'd recommend keeping all your loads, whether Autocomp or not, to around 170 and implementing strict QC on your pick up range brass. 

And what was the head stamp on the very first brass failure you had?

The first one was an S&B case with pretty deep cannelure...separated right at the stress concentrator...I mean cannelure.  The others were ammoland and likewise separated right at the step.

Guys, I appreciate the sage advise...I'll back off a couple tenths of grain and get the load down to 171-172 PF.  And scrap all the questionable brass.  I'll try loading a little longer...I assume so long as it isn't hitting the rifling and still feeds in the mag it isn't too long?

I was loading to 178 PF on advice of the dealer I bought the gun from that said the extra gas at that load was a good thing.  I did work up from an initial load of 6.2 grains which yielded a 158 PF checking for overpressure signs along the way.  I tried to be cautious to begin with...even at the starting load it seemed like a heck of a lot of powder given that I'd previously been loading for minor at about 3.3 gr of bullseye...  :-)

Advice on powders other than Autocomp that would be better for a 9 major load?

Thanks again!

Dan

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On 11/7/2016 at 7:41 AM, theWacoKid said:

Cull out FM, IMT, and Ammoload which all have the step.

Rather than add another sorting brass, I just load everything, chamber check and place in plastic ammo boxes, then num my finger over the head stamps, pulling out the stepped cases to be use in practice to check zero or chrono.  I've only had one gun which actually has had any separate (maybe a looser chamber than the rest).

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1 hour ago, kneelingatlas said:

Rather than add another sorting brass, I just load everything, chamber check and place in plastic ammo boxes, then num my finger over the head stamps, pulling out the stepped cases to be use in practice to check zero or chrono.  I've only had one gun which actually has had any separate (maybe a looser chamber than the rest).

My sorting takes very little time so I'll share my method.  Using a 50 count Frankford .40 reloading tray drop over a couple handfuls of brass and shake.  Everything falls mouth up.  I scan for steps, splits, ss pins, etc.  Flip right over into another tray.  Scan again for ss pins in flash holes, crimped pockets, etc.  Done.

I'm not even willing to risk shooting these cases in practice.  Practice time is important and a case separation will cut into that.  Also, if it's loaded there's always a chance it can get overlooked and make it to match ammo.  Even worse scenario.  

Yes, these cases fail more in certain guns and chambers than others, but at the rate they pop overall I'm willing to learn from others and not load or shoot a single one.

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1 hour ago, Dwampler22 said:

How much head space do you have. Barrel could have been reamed a tad to deep.

I agree.  The proper long run fix is probably a chamber more in spec.  I'd have it checked out for excessive headspace or dimensions.  

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