10mm vs 10mm MAG case comparison

[Benchrst]

Did a short comparison (both Starline) of a standard 10mm and a 10mm Mag case.

Can be viewed here: http://10mm-reloaded.com/random/10mm-MAG_cut_down_to_10mm.html

The gist of it can seen with these two images.





Of course this means 10mm with cut down mag cases can be loaded Super Thermo Nuclear!

I'm kidding 

[tommac919]

what's the diif in measurements in side walls ( if any ) near where the smiles occur , near the base

[PCFlorida]

I would imagine powder capacity would be somewhat reduced.

[The_Shadow]

Great info here.  Thanks for the pictures and link Benchrst.

When you look at the base of the primer shelf thickness being thicker, it places the start of the web of the side walls upward as well.  Yes it will also (by a slight difference) reduce the overall case capacity.

Here is my take though...Will the extra cost, work and slight gains be worth the effort?  NO! 
Yea many of us have chased the higher velocities with various powders and bullets of all weights.  Some have actually got to the point of bulged, SMILED and even blown out cases and wrecked guns.

When you buy ammo the cases are NEW and some are more malleable than others.  Powder selection, based on burn rates, can and will affect how the pressure spike acts on the casing.  Faster burn rate powder spikes have been known to fatigue the brass as the pressure spike works on snapping it to fill the chamber.  I have seen many Federal 10mm brass which were split on their initial firing as collected from the FBI range.  These are not high velocity but are up there in pressure loadings.

At some point, you have to use self control and restraints, thus curb the need for speed in the realm of safety.
The safest way for more speed is longer barrels using tried and true loads.

Be safe guys!

[Benchrst]

The intent was simply to satisfy my own curiosity regarding MAG case construction in comparison to the standard 10mm case.

I decided to share what I found, not suggest any course of action.

Could someone safely eke out a bit more performance (even with the slightly reduced case capacity) using cut down MAG brass vs standard? Probably, a little bit.

By the time quality (Starline) brass is compromised the load has surpassed the limits of the design as a whole (gun, conditions, components, etc). Using beefed up brass would be a band aid.

I will be loading up Mag brass for a results comparison, but it won't become part of my reloading practice.

[tommac919]

would be nice if they could squeeze that case into a G40  !

[Benchrst]

Be one hellava grip!

[blaster]

o.k., I am ignorant here.  until very recently I have not even heard of a 10 mm mag. it looks pretty long for a magazine in a pistol grip. what kind of pistol is the 10 mm mag. chambered in ?

[Benchrst]

I believe the Automag was chambered in 10mm Mag, not aware of any others.

[sqlbullet]

The IAI Automag was the only factory chambering I know of as well.

Any 10mm revolver with a "magnum" length cylinder window and cylinder could be reamed to 10mm magnum,  I believe the s&W 610 was the popular platform for these conversions, but I think the numbers were very small.

And, like loading a 40 S&W long for near 10mm performance, you can load a 10mm auto "long" and get 95% of the performance of the magnum without the expense of reaming the cylinders.

However, since the 10mm mag brass is thicker in the head, it's ultimate strength is higher.

[Benchrst]

I think case support is a much bigger factor than brass build (that's not to say inferior brass should be used).

For hunting, why not a 200gr @ 1,250?

Pretty easy with standard Starline brass.

[Benchrst]

I got trolled, didn't I...

Nuts!

[The_Shadow]

Na!  You peaked some interest and raised some questions...

[Benchrst]

Kinda makes me want to section a piece or Norma brass

[Ramjet]

I bet a little Encore Custom barrle in a carbine length 16" would be dandy little rifle in 10mm magnum good velocity from 200 a Grain GC WFN cast.