I know that this is a 10mm forum so let me explain.
I was just searching the web and found where people were asking which is better 45 Super or 10mm, to make a long story short. Found out that Buffalo Bore has a 255 grain load moving out at 1100 fps! Yes the 45 is. 05 larger but why can't we get a heavier (240,250) to do that or better? Not talking revolver just auto. I know some have loaded 200-230gr lead kinda hot but what about going a step or two farther?
Is it possible to say get a 240gr lead or jhp up to say 1100+ out of a standard 10mm, not a 6" barrel? May he RIP Mike from Swampfox pushed a 200gr to 1300 fps 8) would like to know thoughts and ideas about this.
To get more weight the bullet has to be longer as the diameter is set by the bore. Overall length is limited by the magazine and chamber. The longer bullet has to be set deeper limiting the amount of powder used and increasing pressure. Yondering can probably explain it better as he's done a lot of reloading with heigher weight bullets.
I saw something about a 10mm Magnum once.....don't remember if it was done using a longer case like the 45 Super or not. Suppose it would have had to be.......
I still see some advantages the 10mm has over the 45 super.
First is sectional density. In order to get the same sectional density as a 220 grain 10mm, you would need a 280 grain 45. Underwood is making 220 fps with their 220 grain, and as Yondering and I have posited, with a better design of bullet for more case capacity, you could probably get another 50-100 fps from a 220 grain. The 45 Super is just not going to reach those velocities with bullets of the same sectional density. This gives the 10mm a BIG penetration advantage.
Second is energy. 10mm delivers 700ft-lbs with Underwoods current 220 grain load. The Buffalo Bore load you reference is 685 fp-lbs. Advantage 10mm again.
Third is magazine capacity. You get 28-21% more ammo in a 10mm Auto vs 45 ACP/Super.
Fourth is available platforms. Not a lot of 10mm factory options, until you compare it to 45 Super. Same could be said for ammunition availability, but I won't say that since this topic in in the handload forums.
Don't get me wrong, the 45 Super is an impressive platform, and I would never feel under-gunned with one. But I think the 10mm still has advantages.
And, EdMC, you are correct, the 10mm Magnum does have a longer case at about 1.249". No factory guns currently available. IAI made the auto-mag for the cartridge, and you can easily convert a SWW 610. I also think the cartridge has a higher operating pressure, as several articles talk about a lack of bullets made to handle the pressure of the 10mm Magnum. In some of John Taffin's load data we see a 200 gr XTP at over 1600 fps from an IAI automag with a 8.375" barrel. That should put it about 1450-1500 from a 5" barrel. And if it behaves like the 10mm Auto, you could probably make the similar velocites up to about 220 grain. It should easily break the 1000 ft-lb barrier from a 5" barrel with the right load.
Just my thoughts
Right on all accounts. But if iirc the super case is still shorter than the 10mm case, although larger caliber oal is 1.220. So I still think we can get heavier that 220-230 at 1000+fps.
Yeah...I agree. 220 flat base with a .300+metplat should be able to make 1250-1300.
Add 20 grains to the base, I think 1100 is possible...maybe a little better.
With a tan. ogive on a mountain mold design, with an 80% metplat and a .402 diameter with a .330 nose, the bullet length is .745. The 220 grain underwood is loading is a measured .740 and are loaded 1.250. In my guns a 1.260" with a .300 metplat run very well. That means I would actually have more case capacity with a 240 than the Underwood factory 220.
Might have to break out the wallet.....