9mm C.O.L.

[clown714]

i've been loading for my pt99 at 1.122" w\125gr.LRN
works just fine.

then i try the same ones in a CZ-85 and they won't lock up

so i'd figure i'll ask you folks here.

what's your COL for them fine CZ pistols in 9mm.

thanks in advance

clown

p.s.this COL works in other pistols.but as of now is tooo long for 2 different
CZ pistols.

 

[HSMITH]

I load for a CZ75 and stay at 1.15" for it using 115 grain FMJ bullets. Sounds like the CZ is shorter throated and the bullet is hitting the rifling. Drop your powder charge back a tad seat to 1.1" and all should be fine, or pick a different bullet with a more pointed nose.

 

[WESHOOT2]

STYLE POINTS

I use OAL's from 1.108-1.169" in 9x19; perhaps it's the shoulder on the particular bullet you're using.

Maybe try shortening your OAL until that shoulder meets the case mouth, but remember, shortening OAL increases pressure, often dramatically (spelled 'catastrophically'). Decrease charge weight.........

 

[Old Pa]

I load my 9mm to just fit in my shortest magazines and then adjust Herco or Unique powder charge for a 50 yard zero from the full sized guns with fixed sights with a 125 grain bullet. This winds up being good point of aim for my dinky 9mms and everything else and provides full cases with adequate consistent velocity.

 

[Johnny Guest]

I don't have a CZ, clown714, but - - -

I did check a couple of manuals - - -
Hornady Handbook of Cartridge Reloading, Fourth Edition, and
Speer Rifle and Pistol Reloading Manual Number 12.

In 9 x 19mm ctg specs, Maximum C.O.L. shows as 1.169" in Hornady and 1.168" in Speer.

Hornady shows loading their 125 FMJ RN at 1.150 and the swadged lead 124 RN at 1.090.

Speer shows their 125 LRN at 1.130 and 124 and 115 plated RN both at 1.135.

Then I measured a few Factory loads, all FMJ or plated RNs - - -

Blazer plated 115 1.147
Win white box 1.158
WW-II Canadian military 1.157
Sellier & Bellot 115 1.154

All the other factory ammo I have on hand is hollow point.

From this info, I tend to doubt that your 1.122 COL is overlong. Sounds more as if there's some lead shaved off on the case mouth while seating the bullet. Could be that your CZ has a chamber cut to minimum length, while the PT99, with a more generous dimension, allows for seating your loads more easily.

Suggestion: Try seating and taper crimping your lead bullets in two different steps. Back out the die body to where it barely straightens out the belled case mouth as you seat the bullet to, say, 1.130. Then, in another step, put some taper crimp on the case mouth. I used to have this difficulty in combining the two steps in loading lead bullets.

Please let us know the results of your experiments.

Best,
Johnny

 

[zeke]

Both cz-75's owned have a shorter chamber than the other 9mm's, and require a shorter COL so the leading edge of full diameter of bullet doesn't jam into the lede or rifling. The lede (transition from chamber to rifling) is also much shorter than the others.

 

[Mikul]

I load to 1.120" for my CZ-75b and H&K USP.

 

[batangueno]

My friend who is a production shooter using a CZ75 loads a 124 fmj at 1.142 COL. Lots of rounds through that gun without any problems.

 

[DonQatU]

clown714, I'm not sure the OAL is the cause of your chambering problems.

Do you see rifling marks in the lead bullets you tried to chamber? Note when you extract them.

What 125 gr. LRN bullet are you using? Bullet diameter?

Don

 

[Tacblack]

I load OAL of 1.15 for my Taurus and Faustulus uses the same rounds in his CZ, Sig's and Beretta with no problems. Montana Gold 124 FMJ.

Don has a point. With the round that long the bullet may be getting into the rifling. The bullet profile has a lot to do with this. The Montana Gold's have a long tapper to the point, very little of the full diamiter bullet sticking out of the case.

 

[Stealthfixr]

Glad you asked--I've been playing with the same thing

I've been trying several different 9mm powder/bullet size combinations just trying something different. The loads were for my CZ 75BD. Anyway, for a 124gr RN plated bullet, my COLs were 1.125, and they functioned fine--not a single problem. Of course, for a 115gr you can go lower, but 1.125 is the OAL for the 124gr bullet according to my Speer manual. If it is not feeding at or below that OAL, I would wonder if something else it up?

Incidentally, I've found my two favaorite powders for 9mm are AA#7 (takes a heavier charge to be super accurate~8.0gr w/ 124gr RN PL) and Titegroup (great medium to low loads). Unique is also fine. My next test is with Power Pistol as soon as my local shop gets it in stock.

Good luck,

Mark

 

[Zak Smith]

Here's a relevant TFL thread:

http://www.thefiringline.com/forums/showthread.php?threadid=133593

With West-Coast plated RN 124gr bullets, I use an OAL of about 1.130" for moderate plinking loads.
124gr Gold Dots at 1.142" are fine. The ogive contacts the rifling somewhere around 1.160", if I remember correctly.

-z

 

[DonQatU]

clown714, if you don't see were the lead rifling is engaging the bullet on an ejected round, then OAL isn't the problem.

Pay close attention to the crimp diameter and base sizing.

To test for proper base sizing...... take a sized case (empty) and see if it drops easy into the chamber of your pistol.

To test for proper crimp diameter.... take a loaded cartridge and measure the crimp diameter just below the mouth of the case. A crimp diameter of .3785" is optimal for most brands of commercial brass using .356" lead bullets.

Don

 

[Clark]

The SAAMI spec for the 9mm Luger throat dimention is throat starts to taper at .813 + .012" with a diameter of .354 + .004".

The taper is at 2 degrees and there is a reference dimention of the throat getting down to the groove diameter at .9258 + .012".

What does it all mean?
If your bullet is pointy, you can seat out to 1.169".
If your bullet is square [wad cutter], you can seat out to .813"

I personally modify the length and diameter of the throats of my 9mm barrels so I can use 158 gr LSWC and 158 gr XTP .357" bullets seated at 1.169".

 

[clown714]

thank you, for the info


the bullet is engaging the rifleing(Sp).


i'm at a low charge,so i think i'll just seat the bullet a'little deeper.

i'll let you know how it comes out.

clown

 

[zeke]

clown-ya might want to consider seating the bullet you're trying into an un-primed case with no powder. Drop the combination of non-primed, non-charged case with bullet seated into chamber of dissembled barrel. Adjust OAL so this practice round rests in chamber without getting "sticky" from bullet contacting lede or rifling. Then re assemble pistol and ya can also try this practice round for feeding and bullet set back. This is good procedure for any handloaded semi-auto pistol bullet. Even different individual pistols (same model from manufacturer) can have significantly different chamber dimensions. My 75-b compact's chamber and lede are shorter than my full size 75b. The BHPs and Beratta 92fs can take significantly longer COL's.

 

[clown714]

magic # is 1.094 w\124gr. LRN.

thanks for all the replies

just what i was looking for,a mild plinking load

clown

 

[TKHover]

My CZ75B 9mm load is 4.9 gr. Unique with 124 gr. Montana Gold JHP and a COL of 1.090. That COL may seem a little short, but this was recommended to me by a well known Montana Gold shooter. My CZ loves this load and I have yet to have any of these not feed properly...and the load is very accurate.
Tom

 

[wingman]

Had a chambering problem with my cz75 reloads however i begin using the
lee factory crimp die, problem solved. The cz seem to have a tighter chamber,
perhaps one reason for better then average accuracy.