Shooter45:
I just read parts of the sticky on reliability tricks for the 1911. Not too long ago there was a discussion here on the jump from the frame ramp to the barrel ramp. The poster (I don't remeber who) claimed that the transistion should be smooth with no jump. When I pointed out that the Jerry Kuhnhausen book on the 1911 , and the AGI Instructor (well know once head instructor for the college gunsmithing program at the well known Northern California gunsmithing school ... sorry but I forgot the name of the school) said the jump MUST be there, the poster insisted that he learned to eliminate it from a famous (to him??) gunsmith. I think you got it right: the jump MUST be there. Maybe that poster will read this and mend his ways (???).
"Now place the barrel into its slot in the frame and push it back and down until the link support legs contact the back of the slot in the frame. The barrel should rest on the curved support surfaces of the frame. Note the gap between the bottom edge of the feed ramp in the barrel and the forward edge of the feed ramp in the frame. This gap should be at least 1/32nd of an inch, and could be as much as 1/16th of an inch. If there is a smaller gap than this, (or no gap at all), the chambering cartridge can and probably will hang up on the lower lip of the barrel's ramp. That gap is absolutely crucial to smooth chambering. If the gap is not at least 1/32nd of an inch, the solution is to file the bottom of the barrel feed ramp back until that gap is achieved. Then the ramp is re-shaped carefully with files or a Dremel grinder so that the barrel feed ramp is once again close to the bottom of the barrel. Be careful - do not extend the ramp much, if at all, deeper into the chamber, and keep the same upward angle as before. In the 1911 design, the ramped barrel leaves a portion of the case unsupported, and if the ramp is too deep, it increases the possibility of a case blowout. This could have serious consequences for the pistol and for you!"
LDBennett
I just read parts of the sticky on reliability tricks for the 1911. Not too long ago there was a discussion here on the jump from the frame ramp to the barrel ramp. The poster (I don't remeber who) claimed that the transistion should be smooth with no jump. When I pointed out that the Jerry Kuhnhausen book on the 1911 , and the AGI Instructor (well know once head instructor for the college gunsmithing program at the well known Northern California gunsmithing school ... sorry but I forgot the name of the school) said the jump MUST be there, the poster insisted that he learned to eliminate it from a famous (to him??) gunsmith. I think you got it right: the jump MUST be there. Maybe that poster will read this and mend his ways (???).
"Now place the barrel into its slot in the frame and push it back and down until the link support legs contact the back of the slot in the frame. The barrel should rest on the curved support surfaces of the frame. Note the gap between the bottom edge of the feed ramp in the barrel and the forward edge of the feed ramp in the frame. This gap should be at least 1/32nd of an inch, and could be as much as 1/16th of an inch. If there is a smaller gap than this, (or no gap at all), the chambering cartridge can and probably will hang up on the lower lip of the barrel's ramp. That gap is absolutely crucial to smooth chambering. If the gap is not at least 1/32nd of an inch, the solution is to file the bottom of the barrel feed ramp back until that gap is achieved. Then the ramp is re-shaped carefully with files or a Dremel grinder so that the barrel feed ramp is once again close to the bottom of the barrel. Be careful - do not extend the ramp much, if at all, deeper into the chamber, and keep the same upward angle as before. In the 1911 design, the ramped barrel leaves a portion of the case unsupported, and if the ramp is too deep, it increases the possibility of a case blowout. This could have serious consequences for the pistol and for you!"
LDBennett