Need C.O.L. For 155gr RN

[Henri311]

Anyone use Berry's bullets I need info for seating depth. Also need for LRN in 155gr load data any help would be greatly apprieciated. Thanks!

[snuffy]

I'm assuming you mean for 10mm. The only two COLs I've seen for any bullet is 1.250 or 1.260 but I'm far from knowing a lot.

[Aegis]

I load Berrys 155 also in 10mm   C.O.L.  1.255 to 1.260 ..

[gandog56]

My Lee's Modern Reloading second edition has loads for copper plated bullets. They list 4 powders for a 155 grain bullet, 3 sized to 1.256" and the last 1.260"

[The_Shadow]

Here is the thing about the COL/COAL, the shorten cartridge length may provide more pressure for a given load, not a bad thing if you are looking for a few more fps velocity.  Will it be dangerous?  Not really unless you are playing on the up edge.
1.2500" is where most 10mm cartridges run in most guns depending on the bullets of choice.  Yes some guns and magazines will allow the use of 1.2600" + (some squeezing the most performance for the most powder even go 1.2700" if they fit and function), also bullets like those of Hollow Points lack a portion of the nose and some Wide Flat Nose (WFN) cast have wide MEPLAT that interfere with feeding angles and are loaded to shorter lengths like 1.2420".  Your gun will determine if and what lengths work right for given bullets. 

With the plated bullets like Berry's You will want to keep the velocity under 1200 fps, so as not to have the plating stripped off exceeding the performance of the plating.

Also with plated bullets you will need to flair the case slightly more than for real copper jacketed bullets...Why you may ask?  The reason is that the plating can catch on the case mouth during bullet seating (this can happen with cast bullets also).  That brings me to the next point!  You will want to seat your bullets completely to the proper depth without any crimp being applied!  If you don't raise the seating die up enough the casing starts to push in on the casing to start closing the flaring, if this happens as you are seating the plating can get snagged/damaged in the seating process.  This is not good for several reasons...damage to the bullet can cause irregular performance, failure to fit the chamber due to excessive headspace, if bullet material if stuck on the case mouth edge, if this rolls up inside the casing it can cause a wrinkle or bulge increasing the case diameter again not allowing it to seat fully.

Therefore; You should close up the casing and/or apply your crimp in a separate step, after the bullets have been seated.

I hope this helps you get a better understanding and Good luck! 

[Henri311]

Thanks y'all I value all the input I receive!!!

[gandog56]

Here is the thing about the COL/COAL, the shorten cartridge length may provide more pressure for a given load, not a bad thing if you are looking for a few more fps velocity.  Will it be dangerous?  Not really unless you are playing on the up edge.

Here's the problem with that. Berrys recommends keeping velocities below 1200 fps. Otherwise you run the risk of blowing the copper plating to shreds. I know this is about right. I foolishly loaded some copper plated bullets in a .454 Casull case. When I fired it it became a shrapnel machine. Little bits of hot copper flew back and gave me a bloody face. (Yes I WAS wearing safety glasses thank God!), Promptly pulled them bullets and put them into .45 Colts like I originally bought them for, where they worked fine.