40 load data for 10mm? COAL?

[rrw413]

I’m using CFE pistol, CCI LPP, Glock 20, Berrys 155 and xtreme 155/165/180. If you start working a bullet that isn’t in the 10mm data, but is in the 40 data, what COAL should you use? 

 

Thanks!

[slayer61]

Use the COAL that works in YOUR gun. Search "plunk test".

[rrw413]

Sounds good.  Thanks!

[Joe4d]

find a bullet that is almost the same in a published source and start from there. You may have to shorten it to get it to plunk, or lengthen it to get it to feed reliably.. Different brand bullets might have a slightly different ogive. Not so much the point, but the part that first reaches full diameter.
Also keep in mind plated bullets have a max velocity. May or may not work for you. 

[zzt]

"Typical OAL for factory 40sw is 1.135".  For 10mm it is 1.260".  So whichever load data you select for a 40 is going to give you a lot less pressure and velocity in a 10.

 

So I'd suggest looking at 10mm data for a 155 and go from there.  You'll get a little more velocity from plated than jacketed.  Also you'll need the Berry's Thick Plate if you are going over 1250 fps.

[Why]

So it’s always good to measure, but sometimes when working something up, I’ll take a factory round that feeds well in my gun and put it under the seating die in my press.  Run the seating die out to allow the round to go in and then adjust the seating stem down to touch the bullet.  It’s a good starting point and depending on bullet profile should, ensure feeding.  You can make adjustments from there.  As stated before, try to remember to measure and write the results down for reference.

[rhowell309]

"Typical OAL for factory 40sw is 1.135".  For 10mm it is 1.260".  So whichever load data you select for a 40 is going to give you a lot less pressure and velocity in a 10.
 

This ^^^^

I ran some of my .40 S&W ammo through my Glock 20 to test. Ran perfect. I loaded a few rounds of the same load data and bullet in 10mm brass and it would not cycle. I had to add about 10% more powder to duplicate the velocity. The case volume made more difference than I expected.