9mm and COL?

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Wildbillz

Wildbillz

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Hi All
I have some 9mm 125grn cast lead round nose bullets that I loaded up a year or so ago. I loaded these at a COL of 1.130 per my Speer book. With 4.4grn of Unique and the bulk of them at 4.1grns of Unique. I tested them in my Browning Highpower and a Taurus PT92at the time of loading and they worked fine. Then a Pre B Cz75 came to the collection. First run a bullet got stuck in the barrel throat. They will also get stock in a Glock but not as bad as the Cz.

Ok so I understand the shape of the bullet along with the depth of the throat on the Cz is going to cause me to have to seat a little deeper in the case. So I started moving them down a little and checking. I finly got to the point where it would feed and extract without getting the bullet stuck. I now have a COL of 1.030 This looks real short in the case.

As long as I am not compressing the powder? Am I setting myself up for a pressure spike by seating the bullet so low?


I checked my depth on some 125grn cast lead round nose from Missouri bullets and at 1.130 they work fine. So I am making a guess that the shape of the discount bullets I got are what is giving me the issue.


The easy answer I guess is to shoot them all up from the gun they fit at stated lenth and be done with them. Keep to quality mfg bullets from a known maker.:banghead:

Any thoughts on this?
Thanks for your help
WB
 
It's not just the depth of the throat. You also have to consider the diameter.
 
I have to seat my Lee 125rf bullet to (gasp!) 1.01oal with my CZ. It has a very short leade, pretty annoying if you ask me. Just reduce charges accordingly.
 
It's a shame that the gun makers can't get their acts together and realize that customers no longer limit their ammo use to 1908-vintage RNFMJ loadings. For instance, Hornady cripples the 9x19 by specifying the COL for the XTP bullets short of the proper full length, to accommodate the throat on the Model 39 S&W the use as their test gun. Seat those same bullets out to correct full length, and pick up 150 to 200 fps at normal SAAMI pressures. If I had a gun with such a short throat, I'd be getting a gunsmith to open up the throat, not ruin the ammunition by turning into .380+P.
 
Hornady's short OAL has nothing to do with S&W's chamber specs. It has to do with the profile of the XTP bullet as it relates to the shortest tightest chamber spec that exists among 9mm pistols. If they did not do this, some brilliant CZ owner would post his contempt all over the Internet because he lacks the imagination and mental acuity to understand the relationship between a loaded round and the pistol chamber.
 
Furthermore, if one has a chamber that can accept XTPs loaded longer, nothing is preventing him from exceeding Hornady's max data which goes with the short OAL. One can use Sierra's or Speer's data at, say, 1.130" OAL.
 
Looks like a good example as to why you should test your new reloads in the barrel before you try to shoot them. Your barrel is your best case gauge, use it...
 
ArchAngelCD +2

I load 9mm for a 75B & SPO1 Shadow. Eastern Euro pistols are generally designed around a FMJ RN bullet. XDs tend to have a shorter chamber too. The shorter distance to the leade is often one factor credited for the CZs accuracy

When changing to a new bullet for the CZ, it's a simple thing to do a "push test" to see the max length the chamber will accept. Typically HP and FP bullets will need shorter oals than other pistols. Some RN bullets do too, but most don't.
 
Some bullets are just shorter than others, and that alters COL. I've loaded as short as .9 with some bullets in a 9mm. They functioned. (and I was below starting loads)
 
Hi All
Well I fired off some of the ones that I reset the bullets in and had no probulumes with them.

ArchAngelCD
Point taken. I never even thought about it. Loaded them up for the ones I had at the time and just went right to it with the Cz when I picked it up. I have a Sig on the way that you can dang sure bet I will try them in first.

1SOW
Tested them in what I owned at the time of loading. The Cz came into my ownership after the fact. I am guilty of not checking prior to loading it though. I never even thought of it. First time I have had this sort of thing happen.

918v
Och. Dude I din't think I was being contemptuse, just asking if I was running a risk doing it as I have never seated that low.

WB
 
I wasn't talking about you specifically. I was just voicing my feelings about handloaders in general.
 
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