This post is for gun smiths.  It is not to poke fun at anyone but since many professional gun smith are on this forum, it is to share some the things that was brought to them to repair after the gun owner did the work themself or tried to install something themself.  Anyone reading these post can learn from others mistakes and learn from how the gun smith corrected it.  Here is an example from my shop.

A new custom shotgun was sent to client with a Speed IV-S stock as he requested.  The same day I had shipped it, he called and asked to change to the SpecOps.  As I had already shipped his weapon I sent him the specops and told him to send me the SF IV-s back.  I also told him to read the instuctions on how to install the SpecOps.  He was an FFL dealer and I did not give the normal instruction I would a novice.  I soon leaned that having an ffl does not mean one knows how to do a simple install.   A week later he called to tell me his weapon was locked up and he could not get the bolt forward.  I ran through some things and as nothing worked I told him to ship me the weapon.  when the weapon arrived I also could not get the bolt forward.  It was locked back.  I had a hard time getting the trigger assembly out and when I did I saw a grey coating of stuff all in the trigger assembly.  I then looked and it was inside the receiver.  I had to force the bolt forward by prying with a large screw driver.  What he had done was to squrit Loc-tite into the receiver stud and not simply put one drop on the stock bolt as you should.  He could not see how much was coming out of the tube and man it must have been a bunch as it locked up the weapon by welding the action bars to the receiver, dripped down into the trigger assembly and it was TARFU.  To make all this worst, he used some thread lock that he had on hand and it was not the non permentant type.   I had to completely disassemble the trigger assembly and clean every part.  I had to take the receiver and bead blast the mess off it as it would not even chip off, then reparkerize it.  He caused me over three hours of work on this weapon.  A simple stock install turn into a disaster.  this is not the worst one I have had but the worst result from what we all consider a simple job, installing a stock.....I have many more of these that came to me from a do-it-yourself job gone bad.......but I would like to hear from other gun smiths.........

Not a professional gunsmith, but....

I picked up a S&W 1905 M&P at a pawn shop. It had the loosest lockup I've ever felt on a wheelgun, non functional DA(action bound up, but would just barely cycle), slow timing, and a hitch in the action when cocking the hammer. It was cheap so I bought it. When I got it home and opened it up, I first found out that the hammer stud was loose. Easy fix since this one is old enough to have screw in studs. Fixed that and found out DA no longer worked at all. Started looking at other stuff.. The hand had been broken in half and apparently part of it was lost....it was built up by brazing. Also had a hammer from a later model gun in it with the newer style DA sear...which had also been built up by brazing and then too much taken off when refitting it––the reason DA totally binds up. The cylinder stop had also been narrowed for some reason, which was the reason for the loose lockup...it was literally so bad I was afraid to shoot it.

Some people shouldn't be allowed near anything mechanical, and especially not firearms.

ETA––-I replaced the cylinder stop with one from a later M10, which required a lot of stoning. I still haven't gotten around to the hand or the DA sear...found some original parts and need to get them ordered.

The one thing that sticks in my mind (and a job that I obviously turned down) was this:

A fellow calls about stocking a barreled action. “I've started on it but the actions screws don't exactly line up with the holes” he says. When he brings in the parts I see he has some none descript walnut stock off another rifle. He has tried to alter the inletting, probably with a cold chisel, then bedded the action with something looking like Elmer's Wood Glue. The action is a Remington 710 (no recoil lug...the lug is part of the 710 stock)  and he wants me to drill and tap a blind hole into the barrel about 1” forward of the action for that front action screw. Somewhere along the process the stock wrist had cracked and what looks like a #10 wood screw (no glue this time) was dremeled off flush with the wood...but “don't worry about that crack, I fixed it myself “ he says.

We had  short discussion about inletting, stock repair, glass bedding, and recoil lugs all the while I kept saying “No, I can't fix this for you”  

There is a continuing stream of Nylon 66 rifles, Ruger 22 auto pistols, and such that are brought to me in plastic bags because the owner “loaned them to a brother, cousin, kids, who tried to take it apart for cleaning (the owner never admits to taking the gun apart)

One thing related to your loctite filled action....Fellow brings in a Ruger 10/22 that was working fine until he mounted a scope. The next day it will not fire at all???. The loctite he used on the base screws dripped into the action – right into the firing pin channel on the 10/22

had a guy show up to me one day with a beretta 92FS with a  bunch of random pipe fittings and other junk hanging off it.  he was really proud he had made a replica of the deacons weapon from "waterworld".  his only problem was the slide refused to cycle.  after dremeling off some of the piping parts i discovered he had welded the slide to the barrel.  i handed it back and told him to send it in to beretta and see if they could help.

the other that comes to mind was the guy who was trying to make a double rifle by welding one left handed and one right handed bolt action rifles together.  he needed me to cut the recivers so it would be a break action.

SW

This is the winner so far
CEW

Had a amateur smith who is pretty good bring me a barrel that he tried to install a choke tube in. He had rented a choke tube reamer set from online and miss measured the bore and the outside wall.  So the reamer cut through the wall of the barrel.
Problem was it was a vent rib. He had cut some it off to reduce the length and he brought that with him.  So I ordered a outside tube from Brownells and turned the barrel in the lathe and solder the tube on. I fitted the vent rib on the tube and epoxy  (JB WELD)to the tube and cut rib so as not re solder the  tube.

He learned a lesson and I made  some money
CEW

These are better examples then I had ever hoped for.....keep them coming as there is a reason for this.

I'm not a smith but work in a shop with a couple.
Worst one I have heard of (didn't see) happened earlier this year. A guy brings in a wrecked (blown up) new Colt Gov't Model. Long story short, he had a bunch of .45 Colt ammo at home and couldn't get it to fit in the gun! So he chucked it up in his drill and filed off the rims. He managed to fire three or four of them (single loading) before the gun quit on him.

I have quite a few "Drill and Tap" stories but one that jumps to the front is the guy went to install his own Trijicon GR sights. He went to the local auto parts and they did not have wire sizes and the guy sold him a bit and tap that he said was close to the sizes he wanted. The guy drills the first hole ok ( but of course it was to big )but put the rear one 90 degrees angle from the receiver instead of straight down. He got fustrated and tried to redrill the hole and of course enlongated it. Now niether of the screws that came with his sight would hold so he just use some kind of liquid steel to mount the screws in. The sight kept coming off so he sends it to me with a refinish job on the weapon. I had no idea what to do so I went to a local gun smith and he told me what to do. I over drilled the holes tapped them and put screws in the larger holes, cut the screws off flush with the receiver so they acted like plugs. I then drilled and tapped the cent of plugs to the correct size and after parkerzing the receiver I installed his rear GR sight. I have seen some real mess from guys trying to drill and tap for scope bases and other things. Best advise, learn on flat bar stock before you try it on you weapon. I FUBAR'd some stuff learning so I speak from expirience

Watching and waiting with baited breath.

Rob

This one isn't a frequent repair job.
It is a bang your head against the wall replacement job.

Why do guys continue to insist on firing steel shot loads through older fixed choke shotguns???

My employer will not allow me to post pictures of the boo-boos I have to fix or I would litter the net with more pictures of flower petal muzzles and blown out barrel side walls than most guys would care to look at.

Replacement choke tubed barrels and cheapo Mossberg and Remington pump guns can be found at every discount house.

Replacing the barrel on an original Model 12 Winchester or sending an older over/under back to the manufacturer to have a new set fitted ain't cheap.

Out of curiosity: do you see this with all fixed chokes, or just full chokes? I've never seen or heard of a major problem shooting steel through an old fixed choke gun as long as it was modified or more open than that. Thanks for your thoughts.

Had one guy that had new 500 he had a lil rust on barrel. HEHE. HE went over to the blueing stuff and grabbed the blue and rust remover. later he brought the gun back, HAHA the finished looked like melted plastic. HAHA

I don't recommend shooting the stuff through any fixed choke but modified and full chokes are the ones that flower petal and split.

To add to that, I don't recommend shooting a lot of steel shot through regular choke tubes unless the shooter is willing to pull the choke tube every day and keep it well lubricated.
I recommend extended choke tubes that place the actual choking in front of the barrel muzzle because steel shot can peen the choke tube into the muzzle threads with heavy use and the tubes can become all but impossible to remove.

I have read that a lot of steel shot through a barrel will eventually create a slight swell in it just about where the choke tube begins. Have you noticed this?

Yes I have and it seems to come from steel shells that use heavy shot cups.
Use a load that doesn't have a shot cup you risk scoring the barrel walls.
Use one that does and you risk ringing the barrel.
Somebody clue me in on the real good that steel shot does, a cripple that is shot with steel is going to die just as sure as a cripple hit with lead.
Nobody can conclusively prove massive numbers of scavenger animals die eating lead crippled birds, the lead shot sinks in the bottom mud long before birds have a chance to ingest any great numbers and the fish are already poisoned by the toxic chemicals that are released in the waterways basically unchecked. My personal opinion is so what if the scavengers die off, the place is overrun with coyotes now, no fox, very few rabbits, gamebirds are way down and it isn't because of leaad shot, the stuff has been outlawed on waterways for better than twenty years now.
The ammo is overpriced, still not as effective a killer as lead shot, it leeds to even more cripples and tears up good guns.
Whole steel shot thing is a major joke in my eyes and a bad one at that but the tree hugging, plant eating, herbivores will still think they are making a major contribution to life on planet earth coming up with solutions like steel shot..
I'll step down off the soapbox now.

Yes it's trueaboutsteel shot that's why I recommend extend tubes for steel.
I have first hand expernce , I havemeasured and gauged my brother 870
and heis a heavey duck hunter andshoot steel  in that barrel.
He we to a Nova and retired the 870 to rabbit hunting.
CEW

Here is one that almost caused a major injury and FUBAR to a weapon that I was able to stop. I stated on my web site that if anyone was building their tactical 870 and wanted advice just call as I will be glad to answer any question. a man calls asking about tube extension and which ones are the best. We get to talking and he is telling me about what he has installed on his 870 so far. When he tells me he installed a Knoxx SpecOps and a Vang Comp Dome safety. I then tell him " well that tells me you have not fired it yet" and he ask why. I then explain what will happen and why and that the only over size safety that will work with the SpecOps is the Wilson Combat over size safety......... He understood and thanked me for saving him from a very serious injury and damage to his weapon....He called back a few days later and told me he was able to send the dome safety back and was getting the Wilson. He then told me everything he had done and was intending to do with the weapon to make sure nothing else was unsafe.