In response to the flak that Colt has been catching over their failure to use a barrel with an integral feed ramp on their new Delta Elite so as to provide a fully supported chamber, I’ve been asked to weigh in.
First, a little history of the ramped barrel with the fully supported chamber.
In the mid-80s, when the doublestack .38 Super raceguns were dominating the open classes, it was because a few competitors discovered that they could make major with the old Super if…IF…they loaded 150 grain bullets to near centerfire rifle pressures, and it worked well until they started bursting cases with small powder charge variances, which got ugly in quick time when the hot gases and shards caused sympathetic detonation of three or four rounds in the magazine. Very ugly.
So, they turned to the aftermarket and had’em cobble up barrels with integral ramps which supported the case head as completely as can be done with a self-loading pistol. Problem solved! The higher than proof level Super ammunition didn’t blow their expensive shooting devices apart any more.
But it led to the belief such support was necessary in all calibers that the 1911 is chambered for…even the old low pressure .45 standby…and it just ain’t so. It does sell expensive ramped barrels and gunsmith services to install them, though.
But, the Big 10 is a high pressure cartridge, so they raised the cry that…like the .38 Super shooting devices used by the top guns…it also needed a ramped barrel and fully supported chamber.
Except it doesn’t. At least until some enterprising handloader decides that another 100 feet per second would make the 10mm just that much better…and sooner or later, somebody will blow up a stock Delta and offer it as proof that it “needs” a supported chamber.
As long as the headspace is within spec, and/or the barrel ramp…throat…hasn’t been cut so far into the chamber that it loses support forward of the case head…the webbed area of the case…the Delta Elites will fare just fine with the standard divorced feed and barrel ramps. The 10mm case was engineered around 37,500 psi, and will withstand proof levels which run to 25% higher than SAAMI standard pressure for the cartridge. Just don’t load to proof levels more than once per case. In fact, it’s not a good idea to exceed the maximum 37,500 under any circumstances.
As a wise man once noted: (paraphrased)
The pressures required to accelerate a 200 grain bullet to 1200 fps in 4.2 inches of rifled barrel are more than sufficient to blow your eyes through the back of your head.
If you need more punch than the 10 will deliver, go buy a .41 Magnum revolver.
Stick to SAAMI pressures and the new Colt will be fine. As this applies to the Delta Elite it equally applies to all 1911s.