9mm Oal For A Cz Sp01

[smokshwn]

Stu, Matt, Angus, or anybody who knows: What OAL are you running for the best feeding reliability?

Thanks, Craig

[eerw]

Hey Craig...

I just measured my rounds..

with the 124CMJ montana gold bullet that I am using now..I am using a OAL of 1.125

seems to work fine with my mags and my gun..I haven't altered the feedramp or mags at all.

[revchuck]

I load 125 grain Zero JHPs to 1.14" and they work fine. Hardball works for me at 1.15 - 1.16", and can probably work at about 1.09 - 1.17". CZs aren't finicky like 1911s.

[smokshwn]

Thanks a million you guys. I assumed the cz's were far less than finicky however I just wanted someone else to pick a number for me so I can start making a few loads.

Thanks again, Craig

[chrisjohn]

1.155 for me.

[ipsc1]

1.098 here with 147 MG

[Matthew_Mink]

1.090" with JHP's, a little longer with FMJ, around 1.100".

[tcurrin]

1.090" with JHP's, a little longer with FMJ, around 1.100".

1.130 with 147JHP

[mrapathy2000]

anybody check to see if they are running into the rifling?

[Jadepanther]

1.150

147gr FMJ

6,000 rounds at that through my sig P226 with zero malfunctions.

[revchuck]

anybody check to see if they are running into the rifling?

Not with my CZ-75B or Beretta 92 Brigadier, both with unmodified factory barrels.

[gose]

Thanks a million you guys. I assumed the cz's were far less than finicky however I just wanted someone else to pick a number for me so I can start making a few loads.

Thanks again, Craig

My SP 01 10 round mags wont function with 1.142 OAL, 147 Zero bullets.

[Kevin Kline]

My SP01 or CZ75 (16rd) mags wont work with JHP's loaded to 1.140 or longer. Some of the rounds were loaded to 1.135 and they weren't too reliable either. The round nose bullets would feed a little more reliably than the JHP at those lengths, but I wouldnt even chance it. I have now loaded my stuff down to 1.105. I might even go to 1.090 - 1.100 now that I see Matt's load length.

The problem is with the mags, not the gun. The rounds will not feed up in the mags. It might feed 1-6 rounds, but before the end of the mag, the rounds get stuck around the mag release notch and the remaining rounds on top of them become loose due to no tension. Turn the mag upside down and the remaining rounds fall out. You can see in the mag that the round(s) get stuck on the mag release notch of the mag.

[gose]

My SP01 or CZ75 (16rd) mags wont work with JHP's loaded to 1.140 or longer. Some of the rounds were loaded to 1.135 and they weren't too reliable either. The round nose bullets would feed a little more reliably than the JHP at those lengths, but I wouldnt even chance it. I have now loaded my stuff down to 1.105. I might even go to 1.090 - 1.100 now that I see Matt's load length.

The problem is with the mags, not the gun. The rounds will not feed up in the mags. It might feed 1-6 rounds, but before the end of the mag, the rounds get stuck around the mag release notch and the remaining rounds on top of them become loose due to no tension. Turn the mag upside down and the remaining rounds fall out. You can see in the mag that the round(s) get stuck on the mag release notch of the mag.

Had the same problem with my 10 round mags and Zero 147gr JHP. I'm down to 1.122 and that seems to work just fine.

Edited January 8, 2007 by gose

[Carlos]

1.090" with JHP's, a little longer with FMJ, around 1.100".

What bullet weight & charge?

[chrisjohn]

Something to note, my SP01 is pretty sensitive to primer depth with a cut 15 pound mainspring.

[JayC]

I had the same issues as Kevin with my 147's when they were loaded out to 1.165". I took my 147 JHP down to 1.150" and they feed fine. They would catch at the mag release hole in the mag. Now with my 124 RN that I shot in my old gun, they feed fine in my CZ at 1.165"

[Kevin Kline]

Jay,

You shooting a CZ 75 or CZ 75 SP01?

[JayC]

I'm shooting an SP-01.

[lefty556]

I can't remember OAL, but it just barely clears a Glock mag. I'm running 125 Zero JHPs, with 4.4 gr Titegroup for 1151 fps and a 142 power factor in my SP-01.

[fryeg7]

in relation to OAL, how do flat-point lead bullets (like precision) behave, like round nose/FMJ or JHP?

frye

[WestWorld]

in relation to OAL, how do flat-point lead bullets (like precision) behave, like round nose/FMJ or JHP?

frye

I maybe wrong, but I've always assumed that you want your bullet as close to the rifling (less jump= better accuracy?) as you can get and still feed reliably through the mags...

With RN plated, I'll load to 1.150... the cartridge drops into the barrel cleanly and I hear the "doink" of the case hitting the end of the chamber. WWB 115 Rn usually runs 1.160-1.166 for comparison.

I tested some LazerCast 124 RN in my SP-01 and found that 1.100 or less would allow the cartridge to headspace on the case mouth.

I dropped some Ranier 124 FN in at 1.140 and found the case protruded about .030 too far out of the chamber. I finally had to drop it to 1.070 for proper headspacing. (remember shorter oal = higher pressures so adjust powder accordingly)

I have become an advocate of pulling the barrel out of your pistol, making up one cartridge that you know is way too long and dropping it in the barrel, then seat that bullet further in small incriments until it finally headspaces on the case mouth. Then write down the dimensions for future reference.

Please clear up any falicy's I may have included.

[JayC]

West, you are correct. Usually loading long will give you better accuracy. The problem with the SP-01 though is that certain bullets (147g JHP) get caught and hang up on the cut out for the mag catch. This brings all feeding to a halt.

Now when I first got my SP-01 I still had some 124g RN Berry's left over from last year. With that bullet design, I was able to load them to the same specs as for my old gun. I could load those to 1.165" OAL and never had a feeding issue in the 3000 rounds that I shot of those. I made the switch to the Zero 147 JHP this year and that is when I found the hidden little secret of the SP-01 mag and this bullet design

I think it all boils down to who's bullet your using, material it's made of, and what the design (ogive, etc) is like.

But as you stated, the shorter you go with OAL, you may need to adjust your powder charge. Same with going long, if you get too long you can cause pressures to go up.

I have also found that some of the faster powders get better accuracy with a shorter OAL. I don't know if this is due to the pressure they build, esp in a 9mm, or if it is due to a related pressure spike.

This post almost brings up more questions than answers

[ima45dv8]

.....and that is when I found the hidden little secret of the SP-01 mag and this bullet design

Unfortunately, I discovered that very same thing. Pictures >>here<<