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Discussion Starter · #1 · (Edited)
I see a lot of problems with feeding that can be attributed directly to an improperly machined feedramp.
When the feedramp is done correctly, there is NO need for elevated mag catches or special magazine designs that present the rds higher than original 1911 specs.
Several of the 1911 clones, yes even those by the top of the line semi-custom shops, are crippled by shallow feedramps.
A proper feedramp extends south of the top of the frame to a .420" depth and is cut at 31 to 31.5 degrees. The bottom of the feedramp should be just above the bottom of the slide stop lug cutout.
I've seen guns done by big name shops that have feedramps only .280" deep.
They will work with ball and sometimes with selected hollowpoints through selected magazines, but they still are not 'right'.
I'll take pics of the next one to cross my bench, and of the process to correct the geometry.
 

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I too will be watching

Bookmarked and waiting. I think I'm going to need a second job to pay for the habit I've developed hanging around here. Plus, I need a bigger safe.

Robert
 

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Me, too.
 

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More knowledge/ information from DA MAN!!!! Thanks in advance for the tutorial Chuck, we will all be waiting.

Hope all is well down south
Mark
 

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Right on Chuck! For years, I would fix bad ramps on new receivers but I finally got tired of it and started sending them back to the manufacturer. They'd cut them properly and return, but never so much as a "Sorry 'bout that." Then with the new CA laws, no more receivers could be imported so the problem went away...at least for us victims of the brilliant politicians.
However, we do still enounter them on complete pistols from a couple of manufacturers.
I'm eager to see your pics.

Bob
 

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Hi Chuck,

I too have been a proponent of the .420 feedramp. Based on ser 70 and earlier guns that feed hollow points.

So we too the time to do a cad drawling of the ramp and where it ends.
the print does not call it out per se......

the frame dimensons are based off the slide stop.

the grip angle is 17 deg 30 min
there is a distance to the center of the front radius of the mag well.
and you can get two different numbers based on the width of the opening
(.551 devided by 2 or in another view a .270 radius.)

next the ramp angle is called out at 31.5 degrees, now you have to extend both lines and see where they intersect, next measure from the rail top down.
(.450)

best guess from here is from the top rail to the intersection of the mag well is .3596

This could easly be wrong as there are several calculations in there to get this number.

Lets asume the top of the ramp is fixed (you have the barrel gap to deal with and on some guns you can pick up some room there also)

each 1 degree in angle lenghtens the ramp .030 (from the rail down dimension)

Yes the factory guns with the 1/4" deep ramps will not feed hollow points.
Peroid.
Hence an entire cottage industry taking guns that cost from 300 to 2000.00 plus and getting them to work :)

and with .400+ there is a great chance the gun will feed hollow points.

If the "GI PRINT" is .360 deep what would you expect the frames from various gun companies to come through at?

Our little cottage industry did lead the GI 45 into a gun that today that comes with beavertails, bigger safeies, better sights, better triggers, etc.

Perhaps our work is not done?
When people speak of out of the box reliability, we still hear Glock Sig etc.
1911 is not at the top of the list. Save for Custom ones, and not all of those.

When I started working in 1986 it was common for a guy to walk in with a ser 70 colt and say it does not work. We would reply Right.
it needs this and that just to work, than better sights, perhaps a beavertail, a trigger job, just to be shootable.

geo
 

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Can't wait Chuck....bring it on! Lord knows I'm all for a little "skoolin"...
 

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Good post!

It would be interesting to hear which production 1911's come with the proper feed angles...or most of the time anyway. :D

Or, do they vary enough within their own brands, i.e. a "Monday" gun versus middle of the week.
 

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Pistolwrench and Mr. Smith, Thanks for the hard numbers and your ideas on feedramp construction. Would it be possible to get the same kind of numbers for .38S/9MM and .40/10MM optimum ramp demensions?
 

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Nice thread.
I have to agree with George Smith. We try to keep it around .360. I am enclosing a sketch I made concerning the determination of this dimension based on the government drawing that was last revised in 1975.
I've asked Ernie, the man in charge of frame production to keep a close eye on the ramps and to keep them on the long side.
http://www.caspianarms.com/gimages/feed_ramp.jpg
 

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Interesting. I've owned several 1911's with what would be considered a "shallow" bullet ramp, and they've all been extremely reliable with JHP ammo, even GI mags no less. I also owned a few with bullet ramps that I felt were too deep and sure enough they had feeding problems. I guess there must be a magic angle and depth that is "just right".
 

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I examined two guns from a big name semi-custom shop the other day and the feed ramps on both were almost verticle. The owner could not chamber a hollow point round without it impacting the feed ramp straight on which caused bullet set-back. He tried several different brands of ammunition and magazines, same results. he sent the guns back to the mfg and a week later he got them back. They said they were ok and that he should load only six rounds in the mag to chamber a round! They are now for sale.
 

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Would someone just make it simple for me and just draw a picture? Like here is the problem and here is like it should be? I smooth out all of my feed ramps with emory cloth but never exceed a half inch or so. Great post and great forum. Many thanks.
 

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Took a few of the children out of the safe and examined the feed ramps tonight. I cant wait to see these pictures.

Would be happy to submit a vintage 70 series for before and after photos :biglaugh: :biglaugh:

Thanks

RD
 

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Are there any photos available? I feel the feedramps on my (2) new Dan Wessons are too shallow. I get a lot of FTF'f where the bullet is forced into the feedramp....
 
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