I guess you dont have the reloading manual from H&N.
125 grs RN HS .356
4,8 grs N 340 Vita..
330 m/s (not f/s)
OAL 28,9 mm
124 HP HS .356
6,2 grs Alliant Blue Dot
319 m/s
OAL 28,0 mm
no warranty, no nothing, at your risk
I am using the 100 grain bullets and LongShot. H&N recommends a load that has more powder then hodgon recommends. That may be because the load is safe to CIP, which should be more or less equal to SAAMi P+. Remember: the CZ are tested to meet CIP specifications ...
Thank you
Grefwen:
A lot depends on the tolerances of your equipment and scales. What type of equipment are you using, and do you have access to a chronograph?
As you seem to be aware, you are dealing with three issues and/or potential problems.
Based on the H&N data provided by Reigen, and the data from VihtaVuori/Lapua (
http://www.lapua.com/en/products/reloading/vihtavuori-reloading-data/relodata/6/34 :
You are using a bullet that is likely to be larger in diameter than both the 125 grs RN HS .356 or the 124 gr. Rainier RN (typically also @.356" in my experience). I am not familiar with the H&N plated design, construction, or actual plating alloy. I suspect the bullets you have are @ .358" actual diameter.
The listed OAL for both loads is longer. Additionally, the Rainier is RN, while the H&N is TC, so your effective OAL is @ 1.09-1.10." This is consistent with my 85 Combat with TC/SWC, by the way.
I have not used VV N-340 with plated bullets. I have never even heard of H&N before today. I am not expressly endorsing the following recommendations as safe in either your or my particular 85 Combat. Based on the above, I would recommend a starting load of 3.5 gr. VV N-340. For now, I would consider 4.0 gr. as your effective maximum. I would load 10-20 check loads at 3.5 -4.0 gr. at 0.1 gr. increments. If the groupings and/or POI/POA improve as you go higher, then I would re-evaluate and load some check loads possibly as high as 4.3 gr.
If that represents a major dent in your supply of this bullet, my honest recommendation is to load them in .38 Special/.357 Magnum only.Just to clarify, the CZs are rated and tested to CIP specifications, but most 9mm ammunition bearing CIP markings are not particularly high in velocity and pressure. (At least, not the loadings sold in the U.S.)
I haven't bought a model with the newer style of manual, but all of the older manuals from the CZ-USA imports explicitly state that you should only use ammunition complying with the CIP and/or SAAMI standards (see page 19 of the last CZ 75 series manual). The orange manual issued with my '86 Type A (manufacturer is identified as AGROZET National Enterprise in Uhersky Brod) is not explicit, but it is clear from the nominal specs. published in the manual that they are referring to CIP standard 9mm Parabellum.
Most 9mm factory loads with the CIP markings are closer to nominal SAAMI standard pressure/standard velocity 9mm Luger (9mm Parabellum, 9x19mm, etc.). This is more due to the fact that most 9mm firearms work better within certain windows of velocity and pressure. CIP maximum for 9mm Luger is roughly comparable to the SAAMI maximum for 9mm Luger +P. However, most CIP factory loadings are not nearly that high in velocity and pressure (nor are most SAAMI loadings).
CIP and SAAMI are voluntary associations that use different testing procedures and protocols, so these sort of comparisons are inherently inaccurate and unhelpful, by the way.
In other words, the fact that the CZ 9mms are theoretically safe with maximum average peak pressures of @ 38,5000 psi by SAAMI testing protocols doesn't mean that you won't encounter issues, whether pressure-related or otherwise, if you start loading for them too heavy/fast.
Some of this may be "old news" for you, but I thought it might be helpful for other people and/or explaining my thought processes.
