1911Tuner
Moderator Emeritus
Ahhhh.! The Ramp and Throat job. There have probably been more barrels and frames utterly ruined by this seeming cure-all to feeding problems. How often do we see the advice to "Polish the ramp and throat" whenever a feeding issue rears its head? How often does it fail to meet
expectations?
I'm gonna make another one of my flat statements here. Unless the feed ramp in the frame was machined far out of spec, it's best left alone unless the ramper/throater has a full understanding of the process. Few feeding issues can be resolved by tinkering with the ramp anyway. Concentrate instead on the barrel, assuming that the problem can't be nailed down to the usual culprit...the magazine...and the next suspect...the extractor.
In the beginning, there was only the narrow hardball throat, and it was good...until somebody came up with the semi-wadcutter lead bullet so clean holes could be cut in paper targets. Clean holes have a couple of advantages. They are easier to see from a distance...and they sometimes mean the difference between scoring an X and a measly 10.
Enter the throat job. The barrel throat was flared and widened...polished and fussed over...all in the interest of getting the pistol to feed a bullet shape that it was never intended to feed.
Enter Super-Vel, with the hollowpoint bullet. Now, this one had some merit in that it upped the effectiveness of the .45 Auto as a "Manstopper"...whatever that means. It also recreated some feeding problems that became apparent with the H&G bullet.
The biggest problem with feeding hollowpoints was that the leading edge of the hollow cavity would grab the slightest corner and stop the pistol cold. The other part of the problem was the overall length of the cartridge. The optimum length of the .45 round is somewhere between 1.240 and 1.270 inch overall. When the round is shorter than these parametners, it tends to point skyward at a steeper angle as it tries to break over to horizontal to enter the chamber. The shorter it is...the worse it gets. Of course, there is also a limit as to how LONG it can be...but in general, the closer to the above mentioned lengths, the better.
Flaring the throat accomplished one important thing. It allowed the side of the bullet to move a little farther into the throat before climbing the hill...which caused the nose of the bullet to hit the top of the chamber farther forward, and lowered the angle of entry into the chamber. Shorter rounds had a better chance at chambering.
Colt caught on pretty quickly, and began using the wadcutter throat on all its pistols because it also smoothed out the feeding of hardball somewhat, and a trend was set. It also gave rise to the advice to "Polish the ramp and throat." This sent our friends scurrying over to the hardware store to get a Dremel and some accessories, and thus made a lot of money for the barrel makers when the hobby smiths discovered too late that there was a definite limit to just how far one could go with that throat job. There were a lotta blown case heads in those days. After inspecting some of the throat
jobs that were performed, my response was."I'll stand waaay back here
while you shoot."
Flat statement warning:
On a quality barrel throat, there is little you can do to improve feeding, and even less that you can do to eliminate a failure to return to battery beyond a very narrow amount. In any event, you are better off leaving the Dremel out of the picture. You can get into a dark place double-quick with a Dremel and a grindstone. Refer to it as the Highway of No Return.
About all that's needed is to eliminate the sharp corner at the top of the throat, and this can be done effectively with the tip of a good pocketknife. Just lightly break the edge, and don't cut the throat deeper into the chamber. Scrape it all the way around and stop. Use some 400-grit and 600-grit wet or dry paper on your fingertip to dress the area, and use the knife blade to carefully address any tool marks on the throat itself.
Pretend that you are a sculptor when you do this. Then use the two grits of paper to polish the throat with your fingertip. Some would say to use a dowel rod, but I say NAY! If you want a mirror finish, go get your Dremel and use some red jeweler's rough on a felt buffing head, and keep the buffing head moving. The mirror finish is not necessary. Most smiths do it because: A...It's expected. B...it's visual proof that work was done on the throat, and C...It looks purty. In any event, more than about 5 seconds in the Dremel phase is a waste of time and effort...and over-enthusiasm can royally screw up the throat...even with a felt buffing head.
This goes double for the ramp. Beyond smoothing up any obviously rough tool marks, and a little polish with your finger tip and paper, you risk altering the angle of the ramp. Above all, don't round off the corner at the top. It's purpose is to deflect the incoming round higher into the throat, and rolling the corner defeats the whole purpose of the ramp and throat job...and it's permanent. If the rounds nose-dive into the throat farther down than the top .030 inch, you have a magazine problem. If the rounds
catch at the junction of ramp and throat and don't enter the chamber, you have a barrel problem...Remember the .032 gap.
If the rounds enter the throat part-way and stop, you have a stem-bind problem...and if you've broken the sharp edge at the top of the throat, you've done about all you can do to the barrel without cutting away the case head support. Can anybody say...KABOOM..? Most late-production throats already have that edge broken anyway.
In the event that you have to set the bottom of the throat forward to achieve the required gap, your best tool for reshaping the throat is a small triangular file that has had the teeth removed on a belt sander. This makes a dandy scrape that can be used with care and precision. A file will cost you about 2 dollars and any machine shop will probably turn it into a three-cornered scrape for you for a buck or two...or at no charge. Yes,
you can use a Dremel for the operation, but it's better not to. Dremels cut fast. Scrapes cut slowly, and mistakes can be caught while they can still be fixed. Personally, I think there should be a 3-day waiting period on any
Dremel purchase unless one can prove that he is a licensed gunsmith.
Onward...
Tuner
expectations?
I'm gonna make another one of my flat statements here. Unless the feed ramp in the frame was machined far out of spec, it's best left alone unless the ramper/throater has a full understanding of the process. Few feeding issues can be resolved by tinkering with the ramp anyway. Concentrate instead on the barrel, assuming that the problem can't be nailed down to the usual culprit...the magazine...and the next suspect...the extractor.
In the beginning, there was only the narrow hardball throat, and it was good...until somebody came up with the semi-wadcutter lead bullet so clean holes could be cut in paper targets. Clean holes have a couple of advantages. They are easier to see from a distance...and they sometimes mean the difference between scoring an X and a measly 10.
Enter the throat job. The barrel throat was flared and widened...polished and fussed over...all in the interest of getting the pistol to feed a bullet shape that it was never intended to feed.
Enter Super-Vel, with the hollowpoint bullet. Now, this one had some merit in that it upped the effectiveness of the .45 Auto as a "Manstopper"...whatever that means. It also recreated some feeding problems that became apparent with the H&G bullet.
The biggest problem with feeding hollowpoints was that the leading edge of the hollow cavity would grab the slightest corner and stop the pistol cold. The other part of the problem was the overall length of the cartridge. The optimum length of the .45 round is somewhere between 1.240 and 1.270 inch overall. When the round is shorter than these parametners, it tends to point skyward at a steeper angle as it tries to break over to horizontal to enter the chamber. The shorter it is...the worse it gets. Of course, there is also a limit as to how LONG it can be...but in general, the closer to the above mentioned lengths, the better.
Flaring the throat accomplished one important thing. It allowed the side of the bullet to move a little farther into the throat before climbing the hill...which caused the nose of the bullet to hit the top of the chamber farther forward, and lowered the angle of entry into the chamber. Shorter rounds had a better chance at chambering.
Colt caught on pretty quickly, and began using the wadcutter throat on all its pistols because it also smoothed out the feeding of hardball somewhat, and a trend was set. It also gave rise to the advice to "Polish the ramp and throat." This sent our friends scurrying over to the hardware store to get a Dremel and some accessories, and thus made a lot of money for the barrel makers when the hobby smiths discovered too late that there was a definite limit to just how far one could go with that throat job. There were a lotta blown case heads in those days. After inspecting some of the throat
jobs that were performed, my response was."I'll stand waaay back here
while you shoot."
Flat statement warning:
On a quality barrel throat, there is little you can do to improve feeding, and even less that you can do to eliminate a failure to return to battery beyond a very narrow amount. In any event, you are better off leaving the Dremel out of the picture. You can get into a dark place double-quick with a Dremel and a grindstone. Refer to it as the Highway of No Return.
About all that's needed is to eliminate the sharp corner at the top of the throat, and this can be done effectively with the tip of a good pocketknife. Just lightly break the edge, and don't cut the throat deeper into the chamber. Scrape it all the way around and stop. Use some 400-grit and 600-grit wet or dry paper on your fingertip to dress the area, and use the knife blade to carefully address any tool marks on the throat itself.
Pretend that you are a sculptor when you do this. Then use the two grits of paper to polish the throat with your fingertip. Some would say to use a dowel rod, but I say NAY! If you want a mirror finish, go get your Dremel and use some red jeweler's rough on a felt buffing head, and keep the buffing head moving. The mirror finish is not necessary. Most smiths do it because: A...It's expected. B...it's visual proof that work was done on the throat, and C...It looks purty. In any event, more than about 5 seconds in the Dremel phase is a waste of time and effort...and over-enthusiasm can royally screw up the throat...even with a felt buffing head.
This goes double for the ramp. Beyond smoothing up any obviously rough tool marks, and a little polish with your finger tip and paper, you risk altering the angle of the ramp. Above all, don't round off the corner at the top. It's purpose is to deflect the incoming round higher into the throat, and rolling the corner defeats the whole purpose of the ramp and throat job...and it's permanent. If the rounds nose-dive into the throat farther down than the top .030 inch, you have a magazine problem. If the rounds
catch at the junction of ramp and throat and don't enter the chamber, you have a barrel problem...Remember the .032 gap.
If the rounds enter the throat part-way and stop, you have a stem-bind problem...and if you've broken the sharp edge at the top of the throat, you've done about all you can do to the barrel without cutting away the case head support. Can anybody say...KABOOM..? Most late-production throats already have that edge broken anyway.
In the event that you have to set the bottom of the throat forward to achieve the required gap, your best tool for reshaping the throat is a small triangular file that has had the teeth removed on a belt sander. This makes a dandy scrape that can be used with care and precision. A file will cost you about 2 dollars and any machine shop will probably turn it into a three-cornered scrape for you for a buck or two...or at no charge. Yes,
you can use a Dremel for the operation, but it's better not to. Dremels cut fast. Scrapes cut slowly, and mistakes can be caught while they can still be fixed. Personally, I think there should be a 3-day waiting period on any
Dremel purchase unless one can prove that he is a licensed gunsmith.
Onward...
Tuner
Last edited:
