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Discussion Starter · #1 ·
Does anyone have dimensional info on cutting a frame for both the Clark and the Nowlin style ramped barrels? The Nowlin looks like a simple horizontal pass with an end mill (what size?) while the Clark looks like a two operation cut inlcude a horziontal pass with an end mill and then a plunge operation with a mill and possible some blind cutting?

Also, is either one possible with relatively standard milling tooling, or do you have to purchase special cutters?

Once again, same as my other post, I have a machinist friend willing to help me out if I do some research up front. :)
 

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Please see my comments in your other post about the Novak rear sight cut and please, I beg you, have the job done by an established and reputable gunsmith, not an ordinary machinist.

I am being schooled pretty hard around here, that there are no shortcuts. Pay to have the job done right, rather than paying twice - once to have someone "try", and then again to have someone fix the previous mistake and actually do the job properly.

You'll be so much happier in the long run.
 

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Discussion Starter · #3 ·
Kevin,

I appreciate your concern, however my friend has many years experience both as a professional machinist and doing gunsmith work including building a few 1911s and many, many 80% projects. He just has not done the particular cuts mentioned. The last project was to build a pair of 5.45 russian caliber AR-15 uppers out of 5.45 AK barrels, which was no small task, but both uppers run beautifully. In short, I am confident in his abilities as a machinist. The projects *always involve* a pre-planning stage, and there are more than a few projects that have been left behind becuase it did not seem like there was a reasonable chance of success.

Moreover, I would rather have the information in hand and then determine that it is better to go to a 'professional' gunsmith or pursue an alterntive than just give up out of hand.

Most of my best learning has been done by asking questions, digging in, and just trying something. Yes, there is the potential for mistakes, but I don't know of any other way to learn. :)
 

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Ramped barrell

You will find this info. on Clark dvd, Customizing the 1911. Not only do they give the cutting dimensions, but they show how to do it. I don't remember cuts, but he does it in two steps useing a 3/8 endmill on a milling machine. Good luck. Wag
 

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Midway (and probably Brownells) sells a specific end-mill for the Nowlin/Wilson style cut. If you're going to do this, I'd trust the specifically made cutter over a regular end-mill. It runs about $100 and takes around a month to special order. Not sure on the Clark/Para.
 

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kevins garage----please define "ordinary machinist"??? If by ordinary you mean someone that has no schooling or apprenticeship as a machinist then I agree. Other wise see my other response regarding this. Snakeater
 

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A barrel is a hand fitted part with a lot of cut and try. The parts are not consistent enough to just cut to a blueprint dimension and put together.

A friend of mine is a toolroom machinist with 25 years experience. He was totally stymied in his early wishes to adjust his 1911 trigger pull because he could not find blueprints for the hammer and sear. He thought that if he brought them right to spec that he would have a good trigger. A gunsmith taught him about making stuff work in the real world of guns less precise than the stuff he made on the job.

That gunsmith says a ramped barrel is a lot more trouble to fit than standard. Maybe some of the full time gunsmiths who post here will have advice for your machinist.
 

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kevins garage----please define "ordinary machinist"??? If by ordinary you mean someone that has no schooling or apprenticeship as a machinist then I agree. Other wise see my other response regarding this. Snakeater
http://forums.1911forum.com/showthread.php?t=189690

My definition of ordinary machinist, based on the above thread, would be any machinist (apprentice or whatever) that was not a professional gunsmith.

I would have to say that milling a ramp cut in a frame would have to be of a similar difficulty as milling a sight cut in a slide, (maybe slightly more or less, but certainly similar). If you read the above thread, I think you'll see that the consensus there is that some work is simply best left to a true gunsmith, not an ordinary machinist. Further, machine work by a gunsmith is a hell of a bargain even at double or triple the price. Yadda, yadda, yadda. Not my thoughts. :)



A barrel is a hand fitted part with a lot of cut and try. The parts are not consistent enough to just cut to a blueprint dimension and put together.
Hmm, I wonder if a machinist could cut stuff to a consistent blueprint dimension and put it together without a lot of cut and try hand fitting? What do you think snakeater? :)
 

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Cut for ramped barrel

I have cut frames for a ramped barrel without a mill, using a drill press,
hacksaw and files. The major critical point of the cut is the depth of the cut. You want the barrel to bottom out when it unlocks so both sides of the
barrel above the ramp contact the top of the frame while the bottom of the
ramp contacts the cut in the frame all simultaneously.

The gun that I made my own cut is a .38 super commander, and it functions flawlessly.
 

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"He was totally stymied in his early wishes to adjust his 1911 trigger pull because he could not find blueprints for the hammer and sear."

The full set of 1911 armory blue prints is floating around on the web for a little llooking.
It still will not result in anything except an 'armory' trigger pull.

Hand work is required to adjsut the hammer and sear to each other AND the frame hole tolerance.
All those few thousandths add up when the hammer hook is only 0.020 inches deep.

The Nowlin cut can be made with a long flat botom end mill, but a guide that rides on the frame makes the whole thing much safer.
Making precion cuts at the end of a 4-5 inch long ~29/64 end mill does not work very well.
There is a significant chance of flexing the cutting tool and messing up the cut.

You are also going to need a mag well filler and side plates to avoid cruching the frame in the machine vice.

An experienced tool room machinest should be able to do the work.
A production line machinest may have some issues.

Messing it up can mean the frame is scrap.
Mill accordingly.
 

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Midway (and probably Brownells) sells a specific end-mill for the Nowlin/Wilson style cut. If you're going to do this, I'd trust the specifically made cutter over a regular end-mill. It runs about $100 and takes around a month to special order. Not sure on the Clark/Para.
I agree. Regular end mills are not flat on the end. If you move an end mill along a surface, you get a flat cut. But if you plunge straight into a piece of material, the center of the hole will be higher than the edge. And for the W/N barrel, you are plunging straight down (or back, actually) into the frame. Even if you have an end mill long enough to reach that far past the edge of the dust cover, you won't get the flat surface you desire. The cutter designed specifically for this purpose is flat on the end.

The Clark/Para cut is done with regular end mills. It does not matter if the end mill is flat or not, because you're milling a slot, not boring a hole. You can do the entire operation with a 3/8" end mill. However, I do it in two operations, with the first being the milling of the through slot (the portion where the barrel ramp protrudes into the magazine well. This I do with a 5/16 end mill, cutting the center first and then widening the slot to approximately .002" wider than the barrel ramp. The second operation is done with a 3/8" end mill.

I much prefer the Clark/Para configuration, as it requires only one setup on the mill, but that's just my opinion.

In either configuration, you still have to check to make sure the barrel has enough room to link down (and clear the upper slide lugs). And, the barrel needs to come to rest against the frame, instead of it's rearward motion being stopped by the link (the link is not there to stop rearward motion... it's there to pull the barrel down as it unlocks). These conditions may require some changes to the bed. Will Schuemann has a very detailed discussion of this on his website, and he includes instructions with the barrels he sells.
 

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"Regular end mills are not flat on the end."

You need to specify 'center cutting' or 'flat bottom' to get one confugered to plunge and leave a flat bottom hole without translation.
The cutting edge design on the bottom is not strictly radial, but has a tangent offset that allows cutting even at the dead center.

A stock 'end mill' will not leave a flat bottom.
 
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