Author Topic: Bullet Shape for Scorpion  (Read 1599 times)

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Offline 427Cobra

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Bullet Shape for Scorpion
« on: December 10, 2020, 09:39:15 PM »
I bought Scorpion pistol that I plan on SBRing it, I have been reloading for a decade or more, for my Infinity I load 124 round nose in 9mm at 1.170, and 180 flat nose in 40sw at 1.20, does CZ short chamber these things, a 124rn loaded at 1.130 is jammed into the lands, and the bullet stays in the rifling, causing me to pound it out and powder goes everywhere, did I get a dud or is this normal for round nose bullets?

Offline SI VIS PACEM PARRABELLUM

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Re: Bullet Shape for Scorpion
« Reply #1 on: December 11, 2020, 05:02:46 AM »
You should be adjusting your col to the guns throat so anything new needs to be plunk tested and the col adjusted to fit the throat. I wouldn't expect the Scorpion throat to follow what is a generally known aspect of other CZ barrels. Watch the ogive too. Some wide ogives just don't work at all in CZ barrels. The bullets I used to cast years ago for 3rd gen S&W's cannot be safely seated to fit the CZ's.

Offline Duke Nukem

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Re: Bullet Shape for Scorpion
« Reply #2 on: December 11, 2020, 08:46:27 AM »
What I used to find the max OAL for my gun's chamber with a particular bullet is the push test, which is described in this sticky:

https://czfirearms.us/index.php?topic=103620.0

Offline Wobbly

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Re: Bullet Shape for Scorpion
« Reply #3 on: December 11, 2020, 09:27:54 AM »
1. Welcome Aboard !


2. What's not explained very well in open forums or even in reloading manuals is that cartridge OALs for auto pistol cartridges are not a fixed length. Even the OALs in the load manuals are not a "suggestion". Each auto pistol is discretely different and very individual. Therefore, it's up to the reloader to measure their own chambers before reloading begins.

Because this is not explained, reloaders can successfully reload for decades with lots of guns and have zero issues, then one day hit a brick wall. So we're not fussing at you or "preaching" at you. We're saying welcome to the Club ! The information presented in the Stickies at the top of the forum was all developed on this forum by users who ran into the exact same problems. So we're not smarter than anybody else, we simply encountered this issue earlier in our reloading career.


3. Guns developed in Europe generally do better with FMJ or "round nose" bullets because these are the only types of bullets legally available in Europe. They do not have access to conical, JHP, or any of the fancy modern bullet shapes we have in the USA. Slender FMJ or slender RN are the place to start because a "slender" ogive profile results in a longer Max OAL.

Examples: the slender Berry Mfg RN can generally be loaded at 1.150", which the stumpy Rocky Mnt Reloading FMJ has a Max OAL of 1.060". That's almost a 1/10" difference for the same weight bullet in the same cartridge case !! So shape (and thus bullet brand) really matters.

Hope this helps.  ;)
In God we trust; On 'Starting Load' we rely.

Offline 427Cobra

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Re: Bullet Shape for Scorpion
« Reply #4 on: December 11, 2020, 10:12:15 AM »
Thanks for the replies, Wobbly i hadn't considered fmj only being available in the EU, makes sense, I switch from some Hightech coated to Blue Bullets and at 1.130 a live round can be ejected, but I can still see a ring ever so slightly around the bullet, I am going to the range today to chronograph and decide which red dot I'm going to leave on it.

Offline Trippy

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Re: Bullet Shape for Scorpion
« Reply #5 on: January 25, 2021, 08:22:43 AM »
Bravo Wobbly! Point number 2 is talking directly about ME! It wasn't until I got my first CZ (Shadow 2) that any of this mattered to me. All my Sigs and S&W's chambered and extracted anything I put in them after following OAL specs from several different manuals. I can't find a manual anywhere that recommends an OAL of 1.100 for 9mm 124gn fmjrn. Yet, that is what my CZ demands. Add to that the differences in bullet shape between manufacturers (ACME, BB, Bayou, Xtreme), and it becomes very apparent that each time I change to a new or different bullet, I am shortcutting if I don't have the barrel right there with me for the first few loads. Recently picked up some 9mm 124gn rn from Xtreme, Acme (both red, and green 125) and Bayou. Every one requires a different OAL to fit the Shadow. Lesson learned with the first mag I tried to put through it loaded at 1.130.

Offline Wobbly

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Re: Bullet Shape for Scorpion
« Reply #6 on: January 25, 2021, 08:45:29 AM »
Trippy -

Welcome Aboard !

Hope your reloading experience has improved since being with us. We look forward to hearing more from you.
In God we trust; On 'Starting Load' we rely.