1911 Ramp Types

[Swamp Yankee]

Not new to shooting but sorta new to 1911's.

The last one I owned prior to the 3 Dan Wessons I picked up was a Colt back in the eary 1980's.
That said, could someone explain or better yet send me to a website that shows and details the differences between no ramp, (I've got a pretty good handle on this one), the Para/Clark ramp, and the Wilson ramp.
What are the advantages, if any, of one over the other?
Thanks in advance for the responses.
Take Care

 

[Dave Sample]

Are you talking about Ramped Barrels and the cuts to fit them? 1911's have a built in feed ramp in the lower end that works very well if addressed right. This is cut out of the lower end with a big end mill when fitting a ramped barre with a "Built In Feed Ramp" that may or may not have a good angle for feeding reliably. I really don't know that much about the current crop of barrels.

 

[brickeyee]

'Ramped' barrels typically provide better support for the brass than the original colt/browning design. WIth the barrel out of the gun, drop a round nito the chamber and you can see a significant amount of brass at the feed ramp location in a regular barrel. At .45 ACP pressures the brass can hold the pressure.
When IPSC shooters loaded up the 38 super (after trying the 9mm) to 'make major' the unsupported area had a nasty habit of blowing out. The solution to this was to support the shell better, but this required changing the feed ramp geometry slightly. The ramped barrel was born. Nowlin uses one cut to create the required clearance and Clark uses another. Both work fine when performed correctly. The feed ramp portion in the frame is cut away in both cases and the new ramp is integral to the barrel. Even at .45 super levels a non-ramped barrel is fine (says something about the pressures in .38 super loaded to make major).