Monday, March 27, 2006


A friend of mine asked a question, "should I go for 10mm, or just use the +p .45acp". That's a pretty good question, and it prompted me to update my "Lies, Damned Lies, and Ballistics" post below.

I love the 10mm. I’d buy a 10 if I found a gun I liked in the chambering for a reasonable price. Hell, I’m lustfully looking at the Ed Brown 10’s, and I’m wondering real hard about the Dan Wessons.

Then there's also the fact that 10mm ammo is expensive, even reloaded (as compared to .45 brass) and the guns wear out pretty fast. Well at least they’ve mostly resolved the frame cracking issues; for which we can thank Glock. They built a 10mm pistol that you just couldn't break, which forced all the oterh manufactures to fix their 10mm designs from the fragile 1911 conversions. The customer base just wouldn't tolerate broken guns now that someone showed you could do a reliable 10mm.

Given this, my personal choice now is to buy hot hot .45 loads, or to handload up to max safe pressure levels; and shoot them in guns that are rated for .45 super. Of my six .45acp guns, only one isn’t rated for .45 super, and it’s a baby Glock; which would be pretty painful to shoot in super.

As to loads, my commander likes the 185gr and 200gr gold dots about equally, and the higher pressure the better. It’s also happy with the 185gr and 230 gr CorBons, and the 185gr HydraShok, but it doesnt seem to like any 165gr load.

The HK USP compacts (I have two) seem to like everything I throw at them, but especially the 200gr gold dot, the 165gr hydrashok, and the 165gr cor bons. They don’t seem to care for the 230gr loads all that much except in standard ball (which I s'pose is what they were originally regulated for); and as with the commander, the higher pressure the better.

I was hunting around for a load the G36 liked for a while, and I just couldn't find one. My groups were averaging 4” at 10 yards (off hand, but not much better from a rest), and I really started looking at the gun funny. Then I tried some +p+ loads with the 200gr hornady XTP (a hunting hollowpoint), and it was like a miracle. I started getting sub 2” groups immediately, and 1” or so off a rest at 10 yards. The gun is really too small for long ranges, but I’m very confident of it’s performance at 10 yards. I haven't chronod the load yet from the g36, but from a 5" 1911 it specs out at 1150fps for 590ftlbs.

I hate to say it, but I’ve only had the 625 out to the range three times since I picked it up last October, and I haven’t found a load it likes yet. Of course my first attempt was to run a bunch of everything my other guns like through it; and with all of them my groups were pretty mediocre. The gun has great sights, and a great trigger, so I though I was doing something wrong, but two other shooters got the same results, so I figure it must just be load selection. Since the same barrel is used for .45lc models of the pistol (theres about a 3/8” frame gap at the front of the.45acp cylinder), I would think it would like a heavier bullet, but 230gr hardball at standard pressure was jsut as mediocre as the rest. I’ve been meaning to ask Kim what he fed through the thing , because I’m reasonably certain that with the right loads this will be a 2” gun off the rest at 25 yards.

Of course that doesn't particularly matter since it's my bedside gun.

Now as I said, almost all my guns are rated for it, so I COULD roll my own .45 super, but as with 10mm, that brass aint cheap. Plus for my carry guns, there’s really no point. You really need the full 5”; or even better a long compensated barrel to get the most out of it; and all my .45s are carry guns with around 4” barrels, except the 625, which I keep as a bedside gun.

With a 4” barrel, all I’m going to get with the super is an extra 25-50 fps, and a HELL of a lot more recoil and muzzle blast, plus more wear on the gun, and less accuracy. I COULD go to an ultrafast powder to try and squeeze more from the shorter barrels, but how safe would that be?

Now if I had a longslide, or the 625 wasn’t a bedside gun (say I wanted to go hunt some javelinas with it or summat), I’d be rolling up some .45 super right now. In fact next time I head up to the mountains, I'm probably going to do just that.

This is of course one of the advantages of the 10mm, in that a 4” or 5” gun see more benefit from the extra power than a .45 super would. I guess that’s what comes of duplicating magnum revolver ballistics; because the current loadings of 10mm seem to have been designed almost with a 4” revolver barrel in mind. Of course a 4” revolver barrel is actually the same length as a 5” auto pistol barrel because auto pistols are measured from the breech face, whereas revolvers are measured from the forcing cone.

Anyway, the point is that a 4.6" Glock barrel does more with the 10mm than a 5" 1911 does with .45 super. Actually quite a bit more...

Thus the continued lusting after one of those Dan Wessons...