First, get a new recoil spring installed and see if the gun is cycling properly and if this fixed your forehead brass burns.
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ISMI Gunsprings, Made in the U.S.A.
These are a few things I do to maintain my 1911s in "canebrake" running form. IF YOU ARE NOT COMFORTABLE DOING THIS WORK, DON'T!
And as with any modifications, baby steps, make small changes only. You can take more material off, putting it back on requires an entirely different skill set.
Most extractors sold, come rough and not polished or prepared. The following graphic shows the area to check and tune the extractor hook.
The next tweak takes time and patients to provide you with a successful outcome. DO NOT
take short cuts!
Remove the slide and take out the barrel. Take a LIVE
round and slide it under the extractor hook and into position on the breechface. Make a mental note of the extractor’s tension holding the round against the breechface and if the round slid smoothly into place.
If the appropriate prep has been made to the extractor, (see above) the round should slide up the breechface with a smooth, undisturbed movement. If there is an issue, see above.
The following tests are subjective with respect to terms such as gently, moderately and vigorously shake (the slide).
With the LIVE
round still captured against the breech by the extractor hook, gently shake the slide to see if you can dislodge the round. If it falls out, the extractor tension is too light.
Make sure the round did not move and shake the slide moderately. If it falls out or moves on the breechface your extractor tension is about right.
If it doesn’t move or dislodge, shake the slide vigorously. If the round remains captured your extractor tension is too great.
Depending on the results of this test, you may need to adjust the extractor’s tension. If so continue with the following:
Remove the extractor from the slide and inspect for any visual defects.
For tension adjustment, place ~ 1/2" of the extractor tip into the extractor channel and apply pressure to slightly bend the extractor. Baby steps, a little goes a long way! See below.
After each tweak, run at minimum of two mags and note where the brass lands.
If it falls where you want it to, you're GTG.
If you want it to fall elsewhere, start over and tune to your target LZ.