1911 Drop in Barrel

>> As warned, the bbl is not completely drop in on this 5" stainless Storm Lake ACP. It does go in the series 80 with a loose slide to frame fit. <<

Most so-called "drop in" barrels presume the gun is built to original blueprint dimensions. However this in often not the case with some of the clones and copies being made today.

On better-quality barrels the link pin is press fitted. You need to support the barrel lug on a block with a hole drilled through it, and then drive the pin out with a punch.

Since I can't examine the pistol in question, I'm not going to get into a detailed discussion about how to fit it. However I suspect that the barrel may be standing on the link, or the bottom (link) lug may be pressing on the slide stop pin. Unlatch the slide stop and swing it down so that it is parallel to the front of the trigger guard (more or less). Push the slide into battery and then see if the slide stop swings free, or binds. If it does bind, remove the link, and see if the slide can be pushed into battery without the binding you are having now. Then report back what you find.

I would strongly advise that if you are going to do this kind of work yourself that you purchase a copy of Jerry Kuhnhausen's book, "The Colt .45 Automatic - A Shop Manual" (available from www.brownells.com) or (www.gunbooks.com). If the book saves you from messing up the new barrel it will be well worth its cost.

Good. Now remove the link and see if the bottom lug is riding (pressing) on the slide stop pin.

Refering to the "supplied bushing." Is it finger tight in the slide, or do you need a wrench to assemble and remove it?

Also go to your Shop Manual and read page 125 (Final Fit Match Barrel, Bushing & Slide) and in particular note illustration #174. In addition review information on barrel bushings and barrel swing on pages #44 and #45.

Edited to add: Is the other bushing you're using one of Colt's spring-fingered kind?

"Drop in" usually means drop in to the gunsmith and have it properly fitted

I just recently went through this process with a Springfield .38 Super that I wanted to convert to 9mm. I bought a Nowlin 9mm "drop in" barrel and quickly found that it required more fitting than I was competent to do.

I "dropped in" to the local smith and in 3 days and $60 later had a pistol that quickly converts from one caliber to another and shoots great with either.

I guess that if you have the right skills and the right tools the job would be simple. But most "drop in" barrels don't.

Good luck and good shooting.

Test

Assemble the gun, point it straight up and hand cycle it. If the hangup goes away or is much reduced, there's interference with the front corner(s) of the barrel lug(s) and the rear corner(s) of the slide lug(s). Either the barrel is timing into lockup too early, or there's a tolerance stack issue in the location of the lug or lugs...but likely just one. If the hood is a close fit with the breechface, you may be able to solve the problem by taking a little off the face of the hood. Easy! About .003 inch should tell the tale.

The gap at the leading of the throat and the top of the ramp will require a little filing. Set the lower edge forward on an angle with a smooth mill file.
Use a scrape to reshape the throat, but don't set the top any deeper into the chamber than absolutely necessary.

I should have ask you before, "is the barrel stepped at the muzzle?" I just presumed that it was. Anyway, if it is, then pulling the slide back will reduce the tension and make it "finger-loose."

Tuner is probably right - as he usually is - but I continue to wonder about the bushing fit. I consider the fact that things work O.K. with the Nowlin bushing to be an important "clew." ( )

If you have a pair of dial calipers (everyone should) measure the diameters of the barrel at the muzzle, the I.D. and O.D. of the different bushings, and the I.D. of the slide.

re:

The Ol' Fuff whomped me on this'un, it appears...provin' that even a blind squirrel will find a nut once in a while.

Kiddin'...Fuff knows his stuff.

On the foot contact...Find an old slidestop. Put a dab of lapping compound on the barrel feet, and assemble the gun with the stop arm hanging vertically.
Use the stop crosspin as a lapping tool by rotating it back and forth under recoil spring tension. Add more compound to it periodically. Unless the mismatch is large, you should get even contact pretty soon. Be careful to keep excessive compound off the holes in the frame and check it often.

You can fashion a scrape from a triangular file by using a belt sander to remove the cutting teeth from all sides...or you can use the tip of a good pen knife....slower, but it'll work. Just blend the filed flat on the leading edge of the throat into the throat's angle. You'll have to cut the top part a little deeper into the chamber if you follow the angle perfectly, but shouldn't hurt
anything unless you go hog-wild.

E-mail sent...

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Standin' by...

re:

45Auto said:

This gun is really beat, needs rebuilding. Hammer followed 5 times....
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Info! I need more info!

Hammer follows during live fire or finger off trigger when tripping the slide during a reload? Will it follow with the trigger pulled and held during a reload from slidelock?

Does it follow all the way down...or does it stop on the half-cock?

Oh boy! Stop and take a deep breath. You have a whole bunch of issues, and you shouldn't be shooting that pistol until they are addressed. Tuner can (and likely will) help, but his assistance is only as good as the information you give him.

I believe this pistol is far from worn out, but it does need some attention and T.L.C. Doing what's needed piecemeal is a mistake because these problems are sometimes interrelated with each other. Some parts do more then one job.

So start by posting a list of EVERYTHING you know that isn't working right. Then we can go from there.

Edited to add: For more detailed information on trigger pulls and sear/hammer relationships look at the following thread:

http://www.thehighroad.org/showthread.php?t=132013&highlight=jammer

When it rains, it ...

As Tuner has said, "usually when there is a problem the solution is an easy one that isn't expensive." Let us hope.

I suspect the better part of your trigger pull problem isn't so much the spring, unless it has been bent too much. What you need too do is eyeball the hammer hooks and sear nose, and look at the angles. That's part of the reason I pointed you toward Jammer's thread. Use a strong glass to do the looking. Drop into a real photographic shop that has accessories and see if they might have a cheap (used) enlarger lens that is ideal for this kind of worrk. It shouldn't cost much, and it may turn out to be one of the most valuable tools you have. Eyeballing often tells you a lot, costs little or nothing, and it won't get you into trouble.

The cracked barrel lug(s) concern me. If they were the top lug(s) I would expect damage to the slide. If it was the bottom lug I would question, "why??"

re:

The hammer follow...Will it follow to half-cock with the trigger pulled...or only when your finger is off-trigger? With trigger pulled suggests the trigger is nudging the disconnect and tripping the sear. Lock the slide back...pull the trigger and hold it...and (ouch) trip the slidestop to let the slide slam home.
If the hammer doesn't fall, it's probably the sear spring. Bend the center leaf forward a little to put more tension on the trigger. If it falls with the trigger pulled, you've got a sear/hammer hook problem.

Cracked lugs...Suggests an unlock timing problem. Are the top front corners of the lugs rounded off or peened? How about the slide lugs? Lower barrel lug show any signs of battering at the rear? Is the link's slidestop pin hole stretched or elongated?

If the frame's vertical impact surface is located too far forward, the lugs will round off, batter, crack or shear due to the barrel not unlocking from the slide in time to let it whiz past. Ditto for battering of the lower lug.

If the vertical impact surface is too far to the rear, the link will stretch or break. Stretching delays unlock timing with the same result as above. A broken link prevents the barrel's unlocking, and damages the lugs.

If it's too far forward, it can be corrected by having a smith mill the "Bowtie"
in the VIS just under the top so that the lower lug will hit the surface closer to the top. Setting back the portion that's left a few thousandths may also be required.

The same things as noted above will also occur if the barrel lower lug is mislocated. Too far to the rear will mimic the impact surface being too far forward and vice-versa.

Your new barrel sitting too far rearward indicates that the VIS may be too far to the rear. Check by assembling the gun without the recoil system. Insert the slidestop through the link, but leave the arm hanging down. Push the barrel down and back and hold it firmly. The slidestop should swing freely.
At most, any binding should be very light, and you should be able to move the arm by lightly flicking it with your fingernail. If it's in a tight bind, the frame is out of spec in the barrel's vertical impact surface.

Note that a short or long link will also do the damage that you described.
Short won't unlock the barrel. Long will delay it, maybe to the point that it hits the impact surface while it's still partially locked to the slide.

Whew! Fuff's right. This one's plum fulla gremlins.

While it is not likely, it is possible that the slide stop pin hole in the frame is mis-loacted. I haven't ever come across this in a Colt, but have seen it in some other makes.

No, Colt didn't change the ramp dimensions - at least on the blueprints. But a lot of folks that do "feed ramp & throat jobs" do and then find they've made a serious mistake.

I presume that your hammer is the Series 80 style with a ledge rather then a half-cock notch. The ledge is higher on the hammer face then the old notch, which means that when the hammer does fall it is more likely to batter the sear nose. You may be able to stone the sear nose and correct this, but a new sear will probably be necessary. First though, you have to determine just how much damage has been done.

re:

Quote:

"Link swings freely"

Not the link...The slidestop.

As a final check...if you can arrange for the use of a dial indicator...mount the gun in a vise and zero the indicator on the back of the hammer spur.
Slowly squeeze the trigger and watch the indicator needle. If it moves to the negative side, you've got a hammer/sear problem. If the hooks are worn oversquare, you may be able to correct it by squaring them up and stoning the sear primary angle if they're not too badly worn. If the sear has to be cut a lot shorter to get the engagement angles to agree, toss it and start with a new one. If the hooks are worn badly enough squaring them will also "advance" them too far. The gun will function, but the trigger pull may be unacceptable. Maybe worth a try though...

Once again I am amazed by the ability of Fuff & Tuner to guide someone through a repair via long distance.

Often times fixing a gun over the internet is somewhat akin to tuning a guitar by mail.

Tunin' by Mail

BluesBear sez:

>Often times fixing a gun over the internet is somewhat akin to tuning a guitar by mail.<
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Tougher...Much tougher. :banghead:


'Sides...We ain't got this'un whupped yet.