Hardening A Screw

[Shotgun Franklin]

I tried to order a 'hardened screw' from Uberti. They only had a regular screw. So how is a screw hardened?
Can it did be that hard to do?

[Fox Creek Kid]

To do it PROPERLY you need an industrial grade oven made to do it. As well, you can buy a can a Kasenit and do a half azzed job that may work well enough.

[Pettifogger]

Once a Uberti screw has been removed for the first time they are usually very serviceable and work fine.  If you bugger up an original screw, even a replacement Uberti screw is fine unless you try to torque it down like an automobile engine head bolt.  Which screw are you looking for?

[Shotgun Franklin]

The side plate screw on a '73. It was buggered up when I got it and has gotten worst. I have a screw coming but not a hardened screw.

[Fox Creek Kid]

There is yet another option:  a screw slot file. Brownell's sells them. They are however not cheap:

http://item.brownells.com/groups/brownells-screw-slot-files/index.htm

[Pettifogger]

The side plate screw on a '73. It was buggered up when I got it and has gotten worst. I have a screw coming but not a hardened screw.

Once you get the new side plate screw you won't have any problem with it.  Mine has been removed hundreds of times and still looks fine.  Uberti screws are notorious for being very difficult to remove.  Most of them are buggered from people using regular rather than hollow ground screwdriver bits on them and trying to remove them the first time.  Hence, the reputation for them being "soft."  Once loosened unless the owner is really ham-handed the screws are fine.  Don't worry about it.

[Shotgun Franklin]

I never had much trouble with it but it was bad when I got it and once a screw has gone bad they are hard to rehabilitate unless you catch'm early.

[Coffinmaker]

What Pettifogger said.  I spent years and years building competition rifles.  Once Uberti screws have been removed for the first time, they are fine.  Again, what Pettifogger said.  Your not truing to torque down a head bolt.  Tight is just fine. 
With fitted screw drivers, they will last indefinitely.

Coffinmaker

[wildman1]

PGW has replacement screws for the 73's. wM1

[Coffinmaker]

Also, if you must have hardened screws for Uberti guns, VTI Gunparts has them, individually and in sets.  Remember as well, if you have screws coming lose when you fire the gun  more torque is NOT your friend. Blue LocTite is.

Coffinmaker

[Shotgun Franklin]

VTI was my source. They were out of hardened screws.
Now if I can figure out how to get the magazine plug screw out I'll be OK.

[Pettifogger]

VTI was my source. They were out of hardened screws.
Now if I can figure out how to get the magazine plug screw out I'll be OK.

This is slightly confusing.  Are you taking about the magazine plug, which is screwed into the magazine tube or an actual magazine plug "screw" that goes through the magazine plug and screws into the bottom of the barrel?

[Coffinmaker]

If we are talking about the end plug in Uberti '73s and '66s, it can be a royal pain.  I personally use a very wide, very thin hollow ground screw driver bit from Brownells and an impact driver with the mag tube held in a padded vice.
There is also a nifty little tool out there but I forget who markets it (old guys forget things)
Usually, the end plug is partially rusted to its threads and was over torqued at the factory.  If you don't have a small impact tool, I would suggest after soaking the join in penetrant, heat the end mag tube the  quickly remove the plug.
What is important is what you do AFTER you get the plug out.  Scour out all the rust (there will be rust), throw away the OEM spring and follower and replace them with stainless steel.  Lube the inside of the mag tube, follower and spring with "Boeshield T-9"

Coffinmaker

[Pettifogger]

The single most useful tool you can have for working on Ubertis is this miniature impact wrench.  It is about as big as a cigar.  Throw away the bits that come with it.  Standard gunsmith screwdriver tips fit it.

http://www.harborfreight.com/7-piece-reversible-impact-driver-set-93481.html

This little gizmo is also very useful.  Hollow ground.  It has a wide blade for the mag plug and a narrower one for the lever and frame screws.

[rifle]

You don't need an industrial grade oven to harden a screw. If it is soft then it must be made from the 12L14 type steel that has lead and low carbon.Used to manufacture screws to make screws.

Being low carbon the screw can be buried in Kasinet type case hardening compound and heated cherry red in a lil cast iron fry pan on a propane burner with a propane torch to hit the pile of Kasinet from the top.

The trick is to heat the part cherry red for awhile like 10-15-20 minutes while buried in the case hardening compound. When the time is up throw the part,while it's cherry red in water. It will be case hardened. Not half azzed cse hardened but nicely case hardened.

The high carbon steel like a screw driver can be done the same way heating fer awhile tolet the carbon encase the part so many .001's in.deep but....being higher carbon the part would need tempered back so to remove the "brittle" from it. If the part has carbon enough it can get brittle. Low csrbon steelnot so much.

Anywhoooo...temper back the part in the home oven using a lead thermometer right in the oven and look thru the window at it if there's a window. Let it cook at about 375 degrees fer a coupla hours and then turn off the oven and let the part cool completely in there.

It's good to temper back when hardening carbon steel since coming out of the quench after the "heat to cherry red buried in the Kasinet" it will be hard as a file. Might make it brittle. Might be alright since files are brittle but don't break easy.

Anywhoooo....metalurgy is compalated so...if the part is soft and files easy and .like screw heads' deform easy they are usually low carbon and don't need tempered back but...tempered back wouldn't hurt them.

The old timers back in the day after they invented case hardening they just ,as a mater of practice, tempered the parts afterwards(after the heating and quenching).

I bet....the hardened screws they sell are just low carbon steel heated red and thrown in water to harden them some saving the cost of the hardening compound and tempering time.

Anywhoooo...ifin using Kasinet case hardening compound is half azzzed then the wedges I just made fer a Belgian Colt 1860 that a file doesn't cut must be just too danged half azzed.    When I hardened them then went to putting the pins in fer the springs I counter sink the holes a lil both sides then obturate the soft steel pin into the counter sinks and it leaves some metal sticking up that I file off. I didn't have to worry bout filing into the wedges themselves since the file wouldn't cut them.I left them as is...hard and not tempered since I figger they were low carbon anyway.

The trick with the Kasinet or any case hadening compound is to leave the parts cherry red buried in the compound fer awhile just to get the part encased in a thin layer of carbon sos they are supported some that way and don't rust easy.

When I do a trigger job and work the trigger and the hammer I reharden the surfaces where the thin carbon has been removed. Reharden the whole parts and leave them cherry red buried in the Kasinet fer 20-30 minutes before I quench them.

Never had a hammer or trigger wear out on the bearing sufaces that I know of. Never tempered them and never had any break from being brittle.

There iis the old way to case harden too. I've redone frames and triggers and hammers the old way. Putthe parts in the wood and bone charcoal in a closed but not real tight closed crucible of steel. Heat in a wood fire fer an hour or two. Set up to open the crucible close to water so there is an inch or two space sos the oxygen doesn't get to the parts much at all. Just a lil so the parts drag down a lil oxygen with them to help with the colors. The drop is important. Close to the water to keep oxygen off the parts and.....the charcoal needs to be in intimate contact with the parts as they drop into the quench water. That is why rails are put to shotgun recievers so there is charcoal trapped next to the steel as it hits the quench.

Anyway...doing the old time method would be a lil much fer a screw or six.

It never hurts to sit next to a nice hardwood fire at night and enjoy it fer awhile while the parts cook getting carbon infused to the surfaces.

Word of caution.......If you case harden frames of cap&baller Colts always do the tempering afterwards because...the arbors can absorb carbon and bet carbonated clean thru and get brittle and snap. Take the arbors out of the frames ifin you want them as is and not hardened.

Triggers and hammers? Cap&baller triggers and hammers don't seem like very high carbon steel but cartridge guns are. Those hammers and triggers need tempered back after the hardening I'd guess.

Example....when a spring is made and heated and then quenched being made of ,say, 1095 steel they can be dropped and break like glass before they are tempered back. Carbon steel gets really brittle when heated cherry red and quenched. It needs tempered afterwards. Same with carbon steel screws. Most are made of a low carbon steel though.

Anywhoooo, people can harden parts themselves without the industrial grade furnace.
Color case hardening and I use a wood fire.  The Kasinet type harden I use a propane burner and lil cast iron fry pan with a lil cast iron pot on top crooked over to leave a space to shoot propane flame inside to help get the parts cherry red.

When  you quench and harden and then temper the parts never temper carbon steel at 500-700 degrees. You'll get the 500 degree embrittlement where the parts get tempered tough and softer up to or just under the 500-700 degrees and then fer some unknown reason the 500-700 degree temps make the parts brittle.

Stay below 500 or above 700 degrees to temper the carbon steel.

[Cliff Fendley]

I don't know but the hard screws may not be made of the same material as the soft ones.

Kasinite will somewhat harden one made of lower carbon steel but you can't really harden lower grade steels in an oven or kiln like you would with a higher quality hardenable steel.