Since not all frame ramps are created equal with some too shallow to feed JHP's, how does one determine how deep to cut the feed ramp? My understanding is that cutting the ramp to "just above the bottom of the slide stop window" does not work equally well on all frames (tolerance stacking, etc.) and could lead to inadvertent over-throating of the barrel in order to get reliable feeding.
So, anyone have a method they can share on how to determine how deep to cut the frame ramp?
While this may or may not totally satisfy your question it is good information from Chuck Rogers and George Smith.
http://forums.1911forum.com/showthread.php?t=121954
Do you mean you want to take a 1911 frame with an in-spec angle and horizontal location that chokes on HP's and alter it (perhaps putting it out of spec) so that it will - hopefully - not choke on HP's?
However, if you just need the ramp's specs they're on the frame blueprint in our Tech Issues section.
Lots of custom smiths mill the feed ramp deeper for reliable feeding of JHP's. I'm trying to learn what they use as a guide, formula or whatever to arrive at their bottom depth of .420, .360 or whatever it is they stop at.
OK, I see. All I've ever done is salvage a feed ramp by putting an out-of- spec feed ramp back to the Ordnance Dept specs in the blueprints. Don't know a thing about custon tweaking a feed ramp.
There are some dimension not on the blueprints (but which are derived from them) shown here, if they'd be any help: