10mm case lenghth

[bpkmary1]

Although I am not new to reloading, I have no experience in loading auto loads. I understand that the case lentgh is critical but would like to know how critical it is. One reason I ask is because the latest Lyman Manual indicates the case length of a 10mm Auto case shoud be 0.982". I checked the case lenth of some new Winchester 10mm cases and found them to be 0.986". Is it necessary to trim to 0.982"? How much leeway can be given?

 

[Ol` Joe]

One reason I ask is because the latest Lyman Manual indicates the case length of a 10mm Auto case shoud be 0.982

max lgt is max lgt.
The Lyman #48 I have though shows the max to be 0.992 and "trim to" lenght as 0.982. your brass at 0.986" is fine.
Trim to recommended "trim to" lenght any time your brass excedes the SAAMI max.

 

[jeepmor]

10mm guns are fun aren't they?

I checked my RCBS trim chart and it matches Joe's info

I recommend American Eagle plinker brass for reloading. All the hot loaded Starline stuff I've used has splits. Never a split on this Federal product after several whompin load firings.

Hope this helps even though I drifted off a bit.

jeepmor

 

[Shoney]

Your brass is currently within standard tolerances. All straight wall pistol cases actually shrink a miniscule amount with each sizing.

You don't need to trim them, unless you are of the anal retentive personlality.

 

[rcmodel]

The 10mm headspaces on the case mouth.
Take the barrel out of the gun and chamber-check the cases in the actual chamber they will be fired in.

If they don't stick out past the barrel hood, you are good to go.

Straight-wall pistol cases are taper-crimped, and taper-crimps are not nearly as length sensitive as the roll-crimp used on revolver ammo.

 

[bpkmary1]

Thanks

Thanks to all that replied. Yes!!! Shootin' a 10 is great fun.