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 Trouble shooting
wildpower  [Member]
10/19/2010 1:21:05 PM
Hello

What is the most likely cause for failure to return all the way into battery when loading the next rd in a 1911?
It only ac-cures with JHP's . The recoil spring is new and tried to go from 16# to 18 and the same result.

thanks for your help.
dfariswheel  [Member]
10/19/2010 4:59:38 PM
Some possible causes:

Ammo.
Just try a different type/brand of hollow point ammo. Some guns just don't "like" some types. Try something with a more rounded nose shape.

Magazine.
Some mags have problems with the shorter length of many hollow points. Try different mags.

Extractor needs tuning.
The extractor may need to be properly beveled and the tension adjusted.

Breech face may have machine marks or burrs.
DO NOT just assume this and start polishing the face. This ruins more guns than have any actual problem with this.
If you don't see machine marks deep enough to catch a finger nail, don't do anything to it.

Feed ramps may need to be polished.
Again, unless you see machine marks, more guns are ruined than helped. When we say "polish" we actually mean "smooth", not like a mirror. All that's needed are ramps that are smooth. There MUST be a gap of about 3/32" between the frame ramp and the barrel ramp. Virtually all factory guns will be good on this. If there isn't a gap you need either a new barrel or a new frame.

Barrel may need work to eliminate a sharp "corner" where the feed ramp breaks into the chamber.
Again once more, many people just assume it needs work on hearing this and proceed to ruin the barrel "polishing" it.

Much of this depends on WHERE the round is hanging up, just as the round is starting into the barrel, or when the slide is almost closed and the round is almost fully chambered..
wildpower  [Member]
10/19/2010 6:01:59 PM
Originally Posted By dfariswheel:
Some possible causes:

Ammo.
Just try a different type/brand of hollow point ammo. Some guns just don't "like" some types. Try something with a more rounded nose shape.

Magazine.
Some mags have problems with the shorter length of many hollow points. Try different mags.

Extractor needs tuning.
The extractor may need to be properly beveled and the tension adjusted.

Breech face may have machine marks or burrs.
DO NOT just assume this and start polishing the face. This ruins more guns than have any actual problem with this.
If you don't see machine marks deep enough to catch a finger nail, don't do anything to it.

Feed ramps may need to be polished.
Again, unless you see machine marks, more guns are ruined than helped. When we say "polish" we actually mean "smooth", not like a mirror. All that's needed are ramps that are smooth. There MUST be a gap of about 3/32" between the frame ramp and the barrel ramp. Virtually all factory guns will be good on this. If there isn't a gap you need either a new barrel or a new frame.

Barrel may need work to eliminate a sharp "corner" where the feed ramp breaks into the chamber.
Again once more, many people just assume it needs work on hearing this and proceed to ruin the barrel "polishing" it.

Much of this depends on WHERE the round is hanging up, just as the round is starting into the barrel, or when the slide is almost closed and the round is almost fully chambered..


The rd is almost chambered!
hsvhobbit  [Team Member]
10/23/2010 9:52:01 PM
Another possibility that I've seen on Springfields (not sure about other brands) is that the bottom edges of the breachface cut is right at the minimum SAAMI spec (width) for a .45 ACP rim and is often left perfectly square (and thus very sharp). This sharp narrow breachface edge will then dig in to the rim as it's riding up and eat up a lot of the slide energy. Leaving a partial feed jam.

On the rounds where it jams, pull it out and look closely at the rim right around the edge and see if you see any gouge marks. Those can help diagnose this issue.