Dumb question about 9mm data

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dodo bird

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This is the data from imr with 800x for 9mm 125 grain.

It says at the top 125 grain LCN. What does the LCN stand for?
 

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Ah very good. Another dumb question. My bullets are lead round nose. I can use the same data right?
 
At the beginning of this forum, there's a sticky titled "Reloading Library of Wisdom". Click on the first entry by rbernie then go down to the "Plunk Test". You want to make sure your bullet will chamber probably in your particular gun. It looks like the listed COL will be OK, but do the plunk test to be sure.
 
+1 on using the barrel to determine the max OAL/COL and function test for working OAL - http://www.thehighroad.org/showthread.php?p=8864541#post8864541

If you look at the comparison picture below, CN has different length of bearing surface (part of bullet base that engages the rifling) than three RN bullets with different lengths of bearing surface to the right.

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Depending on the working OAL of the RN, your bullet seating depth may vary.

Non-step RN bullets like MBC SmallBall may get seated deeper than published OAL for CN and it that was the case, I would use slightly less start/max charge for my powder work up (like .2-.3 gr).

Stepped RN bullets like Dardas/Z-Cast will likely get seated shallower and you would be OK using the published start charge.
 
Ah very good. Another dumb question. My bullets are lead round nose. I can use the same data right?
yes. Keeping nevadabob's post in mind, and not running max loads, you can pretty much use any bullet interchangeably with load data provided that the bullet weight and material are the same. (ex, lead bullets for lead bullet data, jacketed bullets for jacketed data) Bullet brand, profile, etc does not really matter.
 
Ah very good. Another dumb question. My bullets are lead round nose. I can use the same data right?
Yes. You can use any data you find with the same weight and type of bullet. Lead data with any kind of lead bullet, jacketed data with a HP, SP and other jacketed bullets. Plated and frangible bullets take some more research unless you find data specifically for them.

That OAL look should be ok, but do the drop test as suggested.
 
Thank y'all . Good photo BDS. Looks like I have a zcast bullet.
 

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Since you are using stepped RN, consider this. Stepped RN bullets have shorter bearing surface than CN/SWC bullets. While they can be loaded to longer OAL than 1.125" to reliably feed/cycle in many pistols, I often use 1.125" OAL which seem to seat the bearing surface deep enough in the case neck to produce more consistent initial chamber pressures.

This not only allows me to use less powder but also experience greater accuracy.

Of course, ultimately you should let the holes on target be the judge. If your barrel/pistol works with longer OAL, range test different OAL loads and use the OAL that produces greater accuracy.
 
You load for the bullet weight. Who made it or its shape doesn't matter.
That Dardas "SWC" and the Missouri are also known as truncated cones. Feed really well out of my Inglis BHP. 121 grain cast with Bullseye. 3.5 I think. Never bothered to work up an accuracy load as the pistol isn't up to it.
Plated bullets are loaded with cast bullet data. They are not jacketed.
 
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