9mm Question - CZ Shadow 2

[Kevinkd]

Question for you all if I may (will try to keep it short but may be long).

I've got the 124 gr lee mold and powder coat them. I've got an HK P30L that absolutely hates lead rounds. They have to be sized to .356 to fit (.357 will not plunk in barrel). From my research it seems the chamber can be reamed etc but too much of a hassle and I dont want to have it damaged by a 'professional' that may or may not know what they are doing. The rounds I've loaded work great in friends glocks, sig, beretta's etc. Standard load is 6gr AA5 with the 124 lee.

So since I've got so many made and want to make more, I went and got a CZ Shadow 2 that absolutely loves that load and is super accurate with it. No leading, 2-3" group and repeatable all day.

I thought, well maybe I can size some to .357 and it will be even more accurate. They seemed to open up (not too bad - maybe 4") so I loaded some with universal, unique, W231, longshot and they were decent but not super tight.

Any ideas why the extra .001 would open it up. I would think with jacketed at .355 and me sizing at .356 that .357 would be better.

I'll keep sizing to .356 of course, but anyone have any thoughts? (just got shadow 2 and havent slugged it yet).

Thanks

[wv109323]

I am in the same dilemma that you are. I have a CZ 75B that does not play by the rules. I have tried around 10-15 different bullets with 8-10 different powders. I have tried bullets at .355 , .356, .3565, .3570, .3582 plus jacketed bullets at .355. I have also used powder coating as well as cast and lubed. Bullet weights have been 120g., 125g., 135g.,147g.I used the barrel as stock then I sent it out and had the chamber reamed. My testing is done in a Ransom Rest at 20 yards.
My loads are decently accurate at velocities less than 850 FPS, but trying to make legal ammo for USPSA and the accuracy falls off. An example would be a 125g. bullet at 1000 fps. Loads are powder sensitive with Blue Dot, AA No.7 and TiteGroup showing the most promise so far.
I can not tell you what your problem is but here are some possibilities.1.) The barrel has a 1:10 twist which is tight for a 9mm. The boolits may be stripping the rifling but it seems .357 would be better than .356. 2.) The .357 Boolits may be getting sized down as they are seated where the .356 are not. 3.) The .357 boolits are harder to seat and the bullet seating stem is not holding the bullet in alignment as it is being seated. Do your rounds have the "Coke Bottle swell"?
I am working on No.3 for my problem. My dillon dies allows the swelling if I use the SWC seating stem as opposed to the RN stem. I loaded several rounds thinking the SWC stem would be better suited for my Truncated Cone boolit. The rounds would not chamber in the barrel. I also would get some rounds that would not go off. The same rounds were next to impossible to extract. I was blaming the hard to extract on the bullet nose jammed into the rifling but now think the run out on the round was too much for the chamber causing the round to lock up the slide. Also bullet run out was causing bad accuracy.
My CZ is still a work in progress.

[sigep1764]

I am in the same dilemma that you are. I have a CZ 75B that does not play by the rules. I have tried around 10-15 different bullets with 8-10 different powders. I have tried bullets at .355 , .356, .3565, .3570, .3582 plus jacketed bullets at .355. I have also used powder coating as well as cast and lubed. Bullet weights have been 120g., 125g., 135g.,147g.I used the barrel as stock then I sent it out and had the chamber reamed. My testing is done in a Ransom Rest at 20 yards.
My loads are decently accurate at velocities less than 850 FPS, but trying to make legal ammo for USPSA and the accuracy falls off. An example would be a 125g. bullet at 1000 fps. Loads are powder sensitive with Blue Dot, AA No.7 and TiteGroup showing the most promise so far.
I can not tell you what your problem is but here are some possibilities.1.) The barrel has a 1:10 twist which is tight for a 9mm. The boolits may be stripping the rifling but it seems .357 would be better than .356. 2.) The .357 Boolits may be getting sized down as they are seated where the .356 are not. 3.) The .357 boolits are harder to seat and the bullet seating stem is not holding the bullet in alignment as it is being seated. Do your rounds have the "Coke Bottle swell"?
I am working on No.3 for my problem. My dillon dies allows the swelling if I use the SWC seating stem as opposed to the RN stem. I loaded several rounds thinking the SWC stem would be better suited for my Truncated Cone boolit. The rounds would not chamber in the barrel. I also would get some rounds that would not go off. The same rounds were next to impossible to extract. I was blaming the hard to extract on the bullet nose jammed into the rifling but now think the run out on the round was too much for the chamber causing the round to lock up the slide. Also bullet run out was causing bad accuracy.
My CZ is still a work in progress.

What are you using to expand and bell the case? Standard Dillon 9mm funnels tend to be too small to expand enough for lead boolits.

[Kevinkd]

No coke shape to case (seems to be fine).

Just using standard lee sizing die, neck expander and last is their factory crimp die (which I prefer to their seating/crimp die). It also will get rid of glock bulge.

I did notice that I have to seat the slugs a fair amount deeper (at .356 or .357) to get them to plunk nice in the cz barrel compared to the HK.

Guess for now I'll just keep sizing to .356 and go from there. Super happy with accuracy (thing is like a lazer beam).

Thanks

[armoredman]

I've been shooting that boolit powder coated in MANY CZ pistols for years. I size to .356 and load to 1.095 with exCZellent results with many different powders. I also use the Lee FCD only on j-word bullets, not cast.

[Wayne Smith]

Do a search for some of DougGuy's posts and I think you will find he is far from an 'expert' who doesn't know his business. He is an expert who not only knows his business but can explain it well.

[wv109323]

sigep1764
I am using an aftermarket powder funnel. I think it is a Mr. BULLET FEEDER that has the stepped flair that the bullet can set in the flair. The top is .358 and the other is .353". My bore slugs at .3563 so I size at .3570.

[fredj338]

Bullet deformation? There is no hard & fast rule to sizing lead bullets beyond 0.001" over bore. So just run the 0.356". If they shoot, all that is needed.