PreB 1985 Now it's in my hands!

[CranberryDog]

Just got home from my FFL after picking up my CZ 75 I recently bought on an auction site.  It came with original box, manual, test target, cleaning brush and two mags with matching serial numbers.  This Pre B is unfired and in 99% finish.  The enamel has a minor scratch.  Grips are perfect.  Slide marked Bauska etc.  

My FFL also had a new CZ 75/85 sixteen round mag that fits!  It's a tight fit, but it fits.  

I am in the process of cleaning it.  Very light machine marks on the inside.  BTW, the single action trigger is smooth and light at about 4 pounds. It's 22 years old and looks like it came out of the chute yesterday.  I am a very happy camper.  I will post some pics and a range report in the next few days.

[briang2ad]

My guess is that if you hit the REAR of that other mag with sandpaper, it will fit like the original mags.

[CranberryDog]

Thanks, I will give the sand paper a try.  The mag came from CZ, Kansas and the label on the packaging says "MAG CZ 75/85 9MM LUGER 16 RDS", and the floor plate is stepped.  I am thinking it might be a Retro mag.  Maybe it will work for other folks that have Pre Bs.  Best.

[Walt-Sherrill]

The 16 rounders are a problem with pre-Bs.  

You might have to use a FILE if you're determined to use that mag.  

(Or just trade with someone on the forum who'll swap a 15-rounder for a 16.

[CranberryDog]

Hi Walt, Thanks for the input.  The 16 rd mag fits, holds the slide open, just like the others.  I haven't used it to shoot yet.  I don't understand what the problem is.  Thanks.

[briang2ad]

Its just that I bought a mab that was a little tight, and I sanded in other places and nothing changed.  Then, I noted that it was binding on the rear, and with not much sanding, bam - it was slick and now drops free easily.  (Of course for drop free mag release, you need to bend the mag spring straight)l

[CranberryDog]

Hi briang2ad, where on the rear was it binding and where was the best place to sand?  Thanks.

[Walt-Sherrill]

With most CZs, mags can be made to drop free.  With some non-pre-B mags, they'll just NOT come out of the grip easily,  If you're not having a problem, its fine.

Rubbing chalk on the mag and then inserting it will show where its binding...

[briang2ad]

Walt is right about the chalk.  But I'm pretty sure it will be at the TOP - there is MORE metal at the top rear of the mag well on a PreB.  When I did it, I did the whole rear.  I actually had done some of the sides and shoulders before this to no effect.  I refinished the whole mag in Oxpho Blue.  It is pretty dark, and it now a VERY slick mag - works great!

[CranberryDog]

Thanks again.  I took off the grips and identified the area that causes the problem.  It is at the top rear of the magwell, about 1/2" above the end of the magazine brake.  Using chalk, I could see an area of about 1/3" X 1/2" that showed where the mag rubbed on the mag well.  

I filed the area with a fine mill file for 5 passes and then used 320/400/600 grit sandpaper.  I took off about as much material as the thickness of 2 pieces of stationary paper.  It didn't take much.  Now the 16 round mag functions like the preB mags and it didn't cause the preB mags to to fit loose.  

So now I have a preB CZ 75 that will accept easily found mags.  Next on the agenda is ordering a Wolff 14# recoil spring.

[briang2ad]

Cdog:

Let me get this straight - you modified the mag well?

That is great - now, you DO have a great PreB.  If that is the case, I think this is the systematic fix to most CZ PreBs - the top rear of the mag well - actually for your gun, it  sounded like an easy fix!

[CranberryDog]

Correct, I modified the mag well.  It was a very easy fix.  I wanted to avoid making it fit the 16 round mags and become too loose for the original mags.  I suggest to anyone that wants to try this to go slow.  We are dealing with cast frames and I would expect that they all vary somewhat in dimensions.

Your suggestion about using chalk is a good one. I guess prussian blue or the like would work too.

Just polishing the mag well would probably help a lot.  There are a few rough spots I will probably polish later.

I am leaving the mag brake in.  The mags do not drop free but do drop about two inches which is fine with me.  Best.

[Walt-Sherrill]

The enlarged mag well won't become too loose for the old mags, as the old mags work properly in the new CZs, too.