CZ Shadow (competition) and Campro 124gr RN

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mook613

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I am reloading some 9mm for my CZ Shadow (competition springs and hammer) with some Titegroup and Campro 124gr RN.
I found that 4.0gr on Titegroup works quite well, and was reliably working down to 3.8 (haven't tested lower than that).

My issue is in determining the seating depth.

I did a push-test using the chamber/barrel out of the firearm. This was done by using a fired case that I dented the neck to allow a little tension on a bullet, but still able to be moved with just a bit of force. I then pressed it in to the barrel a few times and measured. The result was about 1.170".

From rifle reloads, I was thinking that .015" off the lands would be ideal and that would result in an OAL of 1.155". From my searches, it appears that with Berry's RN, everybody loads all the way down to 1.115".
Why is my measurement so much higher?

I also found that when testing some loaded rounds to 1.120", the rounds would not simply drop out of the chamber as I had been told would be a good test to use. I'm thinking that this may have to do with a lack of crimp (other than what the Lee seating die provides).

Should I be loading to 1.155 or go down to 1.115? Would it really matter with a pistol cartridge?
 
I load 3.9 to 4gr tightgroup and seat 1.109-1.115 with a slight crimp for my shadow 9mm minor load. Getting the crimp right is the hard part but once set up on the 650, it’s run through about 5000 perfectly.
 
My experience with my SP01 is that the chamber is not short but "spec." Long bullets, those seated out farther, and those bullets with a RNFT ogive will always jam if set out too far.
My solution is/was to reload all my 9mm suitable for my SP01 including those bullets that have a thicker ogive than the standard 124 RN. Deeper seating means dropping less powder as the bullet sits completely on top of the powder, but it is not a compressed load. My G17 enjoys these deep seated bullets but my M&P feels they are too short.
The SP01 relishes them.
 
CeeZer said:
If you clear rifling at 1.155 then load that. If you load shorter than necessary then accuracy will suffer.
Click to expand...

I've been wondering about this... how relevant is the jump to the lands with pistol ammo? I loaded a bunch of 124 grain campros for my shadow at 1.150", and they functioned fine. My most recent batch I dialed back to 1.120" or so, just because? Is less distance between the bullet and rifling beneficial in any sort of significant way?
 
I Load 4.1 gr.s of TG with 1.120 OAL, this functions in all 3 of my CZ's. If I load the 124 gr Campro's to 1.130 some rounds will not pass the plunk test.
 
Breaker61 said:
I Load 4.1 gr.s of TG with 1.120 OAL, this functions in all 3 of my CZ's. If I load the 124 gr Campro's to 1.130 some rounds will not pass the plunk test.
Click to expand...

I couldn't get any to pass the plunk test, even at 1.120". Assuming that this may have to do with not using a proper crimp die though. Would it be worth picking one up for use in the SP-01 Shadow?
 
Scotty454 said:
I've been wondering about this... how relevant is the jump to the lands with pistol ammo? I loaded a bunch of 124 grain campros for my shadow at 1.150", and they functioned fine. My most recent batch I dialed back to 1.120" or so, just because? Is less distance between the bullet and rifling beneficial in any sort of significant way?
Click to expand...

I load and shoot Berry's 124gr RN and load them to 1.125" due to bullet ogive, that's what my gun likes. I'm on second barrel now and they both like same ammo. Original barrel got retired after about 75K rounds. If you load for multiple pistols then go with lowest OAL so all your guns eat same ammo just fine.
It's not unheard of to have ammo loaded for CZ with 1.06" OAL. Depends on the bullet's ogive.
You don't want big gap and you don't want bullet touching rifling, mind your ammo will vary a bit so play safe to a degree. I think after coming up with an OAL I loaded 200rds and barrel tested them all and then reassessed and readjusted seating die.. I like minimum of 0.005" clearance.
You don't need to be that 'particular' with accuracy unless you expect to shoot mini IPSC targets at 25-35+ meters...

In short - your magazine will tell you how long you can go with OAL, and chamber will tell you how short you need to go...
 
CeeZer said:
I load and shoot Berry's 124gr RN and load them to 1.125" due to bullet ogive, that's what my gun likes. I'm on second barrel now and they both like same ammo. Original barrel got retired after about 75K rounds. If you load for multiple pistols then go with lowest OAL so all your guns eat same ammo just fine.
It's not unheard of to have ammo loaded for CZ with 1.06" OAL. Depends on the bullet's ogive.
You don't want big gap and you don't want bullet touching rifling, mind your ammo will vary a bit so play safe to a degree. I think after coming up with an OAL I loaded 200rds and barrel tested them all and then reassessed and readjusted seating die.. I like minimum of 0.005" clearance.
You don't need to be that 'particular' with accuracy unless you expect to shoot mini IPSC targets at 25-35+ meters...

In short - your magazine will tell you how long you can go with OAL, and chamber will tell you how short you need to go...
Click to expand...

Seems like everybody at my club shoots CZ. Most load between 1.065 and 1.085. But I believe they all use the same 124grn TC mold.
 
I load Campro 124gr RN to 1.100" for all my pistols and they work fine in my Shadow. I have no issue hitting 8" steel plates out to 35 meters if I go slow and really concentrate on my sights. That's at a 128-130 PF.
 
So I just measured my max OAL (Bullet sitting long in an empty unsized fired case, then pressed into battery with the slide) for my shadow and came up with 1.175" with the bullet touching the rifling.

1.1" seems like it would leave a pretty decent jump to the lands (.075", or .050" in my case loading at ~1.125")? Which is why I'm curious about the effect on accuracy in a pistol...
 
Scotty454 said:
So I just measured my max OAL (Bullet sitting long in an empty unsized fired case, then pressed into battery with the slide) for my shadow and came up with 1.175" with the bullet touching the rifling.

1.1" seems like it would leave a pretty decent jump to the lands (.075", or .050" in my case loading at ~1.125")? Which is why I'm curious about the effect on accuracy in a pistol...
Click to expand...

I measured to 1.170", so pretty close.
Wondering the same thing as you.
 
CeeZer said:
SAAMI is 1.169"
Click to expand...

I keep seeing posts saying that the CZ Shadows have small chambers. Based on a SAAMI spec of 1.169 and measuring my chamber at 1.170, it appears that my Shadow is almost exactly SAAMI spec'd. So why do so many people suggest loading it all the way down to 1.115?
 
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mook613 said:
I keep seeing posts saying that the CZ Shadows have small chambers. Based on a SAAMI spec of 1.169 and measuring my chamber at 1.170, it appears that my Shadow is almost exactly SAAMI spec'd. So why do so many people suggest loading it all the way down to 1.115?
Click to expand...

Now try the "plunk" test. Remove the barrel from the gun, take that 1.170" cartridge, and put it in the chamber. Carefully rotate the case in the chamber. Will it spin freely? The case should be resting on the little ledge in the chamber, and the bullet should not be touching anything. You will feel slight resistance if the bullet is hitting anything.

Bullet shape will affect this too. Different brands could be loaded longer than others.

Much of this is covered quite clearly in CeeZer's post #12 above (the link to the other site). You want a safety margin too. Hence the minimum 0.015" setback described in the linked thread.
 
jimbo14 said:
Now try the "plunk" test. Remove the barrel from the gun, take that 1.170" cartridge, and put it in the chamber. Carefully rotate the case in the chamber. Will it spin freely? The case should be resting on the little ledge in the chamber, and the bullet should not be touching anything. You will feel slight resistance if the bullet is hitting anything.

Bullet shape will affect this too. Different brands could be loaded longer than others.

Much of this is covered quite clearly in CeeZer's post #12 above (the link to the other site). You want a safety margin too. Hence the minimum 0.015" setback described in the linked thread.
Click to expand...

I played with the loads last night for a bit.
The reason my rounds didn't previous pass the 'plunk' and 'spin' test is because the case neck was still too flared out. I set my die for a slightly stronger crimp and it solved my problem.
Once I found out that my crimping was an issue, I then revisited seating depth.
Using the push-test, the chamber is spec'd to about 1.170". However, when I loaded to 1.165" there a slight resistance when trying the spin test as the bullet was scraping the rifling. I loaded up to 1.160" and they now pass both the 'plunk' test and the 'spin' test.

Not sure why people load their Shadow's to 1.115" and lower.
I will report back if there are any chambering issues with the OAL of 1.160".
 
mook613 said:
Using the push-test, the chamber is spec'd to about 1.170". However, when I loaded to 1.165" there a slight resistance when trying the spin test as the bullet was scraping the rifling. I loaded up to 1.160" and they now pass both the 'plunk' test and the 'spin' test.

Not sure why people load their Shadow's to 1.115" and lower.
I will report back if there are any chambering issues with the OAL of 1.160".
Click to expand...

ok, you missed two things:

You found with *that* particular bullet, the extra 5 thou of clearance for an OAL of 1.160" passed the plunk and spin test.

You didn't give yourself any more margin of error for variances in bullet shape in this batch.


Weebly clearly outlined the procedure of setting it back 0.015", so you really should consider using an OAL of 1.145", not your "just made it" OAL of 1.160".

Again, bullet shape will vary from brand to brand. Some are more "pointy", and some have broader "shoulders". This shape is called "ogive", and was referred to in a post above.

Just trying to save you from some grief. A few days ago, I was on the phone with a local ammo manufacturing company and the sales manager noticed I wasn't buying from him anymore. I told him about the issue I had with his ammo, loaded to ~1.150", that would occasionally jam in my Shadow. One time the jam was so severe, not only did the gun not go into battery, but it was stuck. I had to grip the slide with one hand, and "punch" the grip with the other, hitting it a couple times. The slide came back, leaving the bullet stuck in the chamber, and powder went all over my arms.

Like I said, I'm trying to save you from some grief.
 
jimbo14 said:
ok, you missed two things:

You found with *that* particular bullet, the extra 5 thou of clearance for an OAL of 1.160" passed the plunk and spin test.

You didn't give yourself any more margin of error for variances in bullet shape in this batch.


Weebly clearly outlined the procedure of setting it back 0.015", so you really should consider using an OAL of 1.145", not your "just made it" OAL of 1.160".

Again, bullet shape will vary from brand to brand. Some are more "pointy", and some have broader "shoulders". This shape is called "ogive", and was referred to in a post above.

Just trying to save you from some grief. A few days ago, I was on the phone with a local ammo manufacturing company and the sales manager noticed I wasn't buying from him anymore. I told him about the issue I had with his ammo, loaded to ~1.150", that would occasionally jam in my Shadow. One time the jam was so severe, not only did the gun not go into battery, but it was stuck. I had to grip the slide with one hand, and "punch" the grip with the other, hitting it a couple times. The slide came back, leaving the bullet stuck in the chamber, and powder went all over my arms.

Like I said, I'm trying to save you from some grief.
Click to expand...

Thanks!
I measured at 1.170" for chamber and dropped it back 10 thousandths (not quite the 15 as per Weebly, but should be okay) to 1.160". There were some rounds that passed the spin test even at 1.165, and they passed the drop test to 1.170".
If there are any issues at 1.160" then I'll drop it down to 1.155 or 1.150.
 
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