Preferred OAL for CZ SP-01?

[Torogi]

I'll be setting up my production gun, got it off the classifieds with the help of bsquirrels

my reloading books says 1.125". What is the ideal/optimum OAL for a SP-01 for good feeding? i've heard of 1.090 to 1.110. I will be using HP-38/W231. I have about 10lbs left and I dont want to get into buying powder again.

also i will be using Missouri Bullets 147gr FP.

Any input will be appreciated, thanks!

[burningsquirrels]

me and a few others use 1.090 no prob.... we do use 124 jhp montana golds (shapr nose) and zero jhps (rounder nose).

[Walküre]

My 124gr loads are loaded out to 1.160" (which is still within 9mm spec; max spec OAL is 1.169" and you can find published 147gr RN data at 1.165") and they feed just fine in my CZs.

ETA - And I haven't had issue running my "suppressor loads" through my Shadow, and they are 147gr RN @ 1.165". (Tthey run just fine through the suppressed 75B as well... haven't tried those loads in my other 9mm CZs though.)

ETA2 - Dug out some of my other load data... I had a 4.0gr WW231 load with 147gr plated RN @ 1.165" that was making ~140PF out of my Shadow.

Edited September 21, 2010 by Walküre

[Torogi]

Thanks for the input.

Now to mention, o-give of the Mo. Bullets Flat-point is still rounded, im not gonna have any issues with it right? i just wonder about non-rounded bullet tip. Bsquirrels mentioned MG JHP and those have FP tip actually.

[ormondopen]

1.115 w/ a 147 through my shadow

(3.3gr N320)

[Torogi]

Also, got a curious question about short loads like 1.090. why? i know it requires less powder to get the PF, more pressure on the case.. but why? i short load too on my 40S&W with my SVI, most load to 1.180 and im loading 1.130. it works. but im curious with the CZs.

[burningsquirrels]

a bunch of cz shooters here used 1.090. i did the same, and i never had a feed issue. accuracy is good and ammo works fine. so, it stuck. :shrug:

[Duke Nukem]

That only matters with JHPs because CZs have short throated barrels and they wont feed JHPs any longer than that.

I use Montana Gold CMJs and can load as long as I want.

Also, got a curious question about short loads like 1.090. why?

[gmg]

3.3 - 3.4 HP-38 set at 1.125 oal using 147gr BBI. NEVER has failed

[BMartens]

For Missouri 147 LFP bullets the chamber is not the limiting factor. If you load longer than 1.150 the nose of the bullets will hang on the front radius of the magazine. Not at the top but lower where the rounds double stack. Causes nose dives and FTF. Also, WSF Powder works pretty good with lead bullets in 9mm.

[NOSAJ19]

1.1"oal. pretty standard for CZ!'s

[sperman]

1.120 - 1.125 with MG 147 CMJ. No issues, but I did have the chamber reamed because it was tight / out of round.

[All-Gator]

Perhaps it's stating the obvious, but, the question isn't finding an "optimal/ideal OAL for an SP01," it's finding an "optimal/ideal OAL for this pistol." I just bought a CzechMate and here are the steps I went through to work up a load for that pistol:

(1) resize a piece of brass and drop it in the chamber to know that the headspace is OK

(2) choose the bullet you intend to use and seat it in the same piece of brass at an OAL which you know is too long

(3) gradually reduce the OAL until it just chambers...having a Redding precision seating die really helps here

(4) load up about five (empty) cartridges and make sure there are no issues with the mag accepting them

(5) hand cycle them throught the weapon. No problems? Load some with a reasonable charge and go to the range. Still no problems?

(6) you've got the max OAL (a desirable feature) that places the bullet immediately before the lands (ie, no "jump"...another good thing)

Now you get to choose a powder...or powders...and start playing with the chrono.

BTW, Using an old-style Zero 125 JHP, I found that 1.133 was the OAL for that pistol. Which is different from the 1.118 that my CZ85 uses with Zero 147 JHP's.

A-G

Edited October 12, 2010 by All-Gator

[rack&roll]

How come nobody here uses 115 gr. bullets in their CZ Shadows? I just bought a Shadow Custom from Ghost, and I've always used 115 gr. bullets in my other 9mm's. (Glock, M&P, etc.) Thanks.

[All-Gator]

Two reaasons come to mind:

(1) the higher velocity required to reach PF means more powder. And more powder means a stronger jet effect at the muzzle.

(2) the twist rate (eg, 1 in 10 for a CZ) better stabilizes a heavier bullet than a lighter one.

But many shooters prefer the "snappier" perceived recoil with the lighter bullet.

A-G

[W_Buck]

So do I need to reduce my powder it I shorten the loads? I was running 4.1 Titegroup with MG 124 JHP @ 1.125 in my Glock 34. Can I use the same load just shortened to 1.090?

[burningsquirrels]

most the CZ shooters here use 3.9 of titegroup behind 1.090" with a 124 mg or 125 zero bullet.

[W_Buck]

What's the typical PF with 3.9 titegroup?

[burningsquirrels]

130-132 PF. I run 4.2 because i can and it's about 140 PF.

[W_Buck]

Cool, thanks.

[cas]

...set at 1.125 oal using 147gr BBI. NEVER has failed

My Shadow is fairly new but that's what mine are with that bullet. I've only shot 4-500 of them though.

I have about 1k of some local, oddly shaped 124gr lead TC type through it... 500 115gr FMJ Montana Gold and 500 Armscor 115gr FMJ, all loaded with the "Uh... I guess that looks good" method.

I've had no feeding issues or problems ejecting loaded rounds.

[W_Buck]

I shot around 1000 MG 124 CMJ @ 1.125 through my shadow with no problems whatsoever. When I switched to the MG 124 JHP, however, 1.125 was too long. I spent my afternoon working up my new shadow load. MG 124 JHP @ 1.090 w/ 3.9 titegroup.

[ardo]

I ran out of my usual FMJs, so I got some Zero 147gr JHPs. My Shadow's OAL with those bullets measured at 1.168". So I loaded a few at about 1.160-1.165", and haven't had a single malfunction - even though a couple had touched the mag wall when loading. Still, I'm going to keep the OAL under 1.150".

If my barrel takes 1.150" with no issues, is there any advantage in doing 1.100"? Sure, it'll take less powder to make the same PF, but isn't longer OAL giving more accuracy?

BTW, I found my 3.2gr N320 load to be the most accurate at 10yds, better than 3.4 or 3.8gr and same as 3.6gr. Does this make sense?

Lastly, love that Zero bullet...