Removing stuck front sight, Steyr LP-10

[m1963]

One of our younger shooters purchased an older Steyr LP-10, and wanted to replace the front sight on their pistol with an adjustable one. They tried to remove the existing front sight (Phillips screw head) and succeeded in stripping the threads. That is how I received it. (By the way, the young persons' parent had already tried WD-40 and heat to remove the screw, with no effect.)

The front sight on a Steyr LP-10 is secured by an M3x5 countersunk screw. (An M3x6 also works- most of the time,...)

From what I could tell someone used red loctite to mount the existing sight.

I used the following procedure to remove it-

After wrapping the barrel shroud in multiple layers of heavy cotton I mounted the pistol in my drill press vise.

Using the other sight location screw mounts on the shroud I determined what the depth was to the barrel and backed off 1/16th of an inch- locking my drill press.

Using a 1/16th bit I drilled directly into the center of the M3x5 screw. I allowed for debris, and used pressurized air to repeatedly clean the debris away.

With the center of the screw relieved I then used a diamond saw bit on my dremel to cut a slot across the full width of the screw.

With almost all internal pressure removed from the screw it broke free and turned out easily, using a normal slotted screwdriver. We cleaned out the existing mounting threads using a quality anti-seize oil, and replaced the front sight using a new- high quality- 10.9 grade steel alloy screw to mount it. (High quality, quenched and tempered, coated steel- not stainless.)

https://www.amazon.com/dp/B0BKSG59LM?ps ... ct_details

Certainly, I would add: if you are unsure about doing this, don't. If you do not have the correct tools, and the skill required to use those tools- don't. If you are unsure whether or not your weapon is loaded, or unloaded- don't.

At the end of the day this was an easy, inexpensive fix. I would suggest to others- loctite is generally not needed on air pistols. Especially, do not use red loctite.


Oh- by the way- Steyr and Morini use the same M3x5 screw to mount their front sights.

[David M]

Not sure how much heat they tried but a high wattage soldering iron directly on the screw until you see fume appear from the thread.
The loctite will usually turn to powder allowing it to be unscrewed.

[m1963]

Armorers often have to find ways to solve problems that someone else created- even decades old problems. Often those solutions are unique to different armorers. But, if it works, it is the right solution.

[Gwhite]

I had to go through this on an LP10 a while back. There wasn't any LockTite, but some gorilla had tightened it to the point that they stripped out the socket. It was a multi-step process, starting with clamping it in my milling machine vise, and making sure the spindle was over the offending screw. Then:

1) Grind the tip on an "Easy Out" down VERY carefully so it will grab the screw socket before it bottoms out in the shallow hole. Also grind down the flutes further up so it will fit in a tapping guide.
2) Soak the screw in Kroil overnight
3) Warm it up with a heat gun (not too hot)
4) Freeze it with aerosol "duster" turned upside down
5) Use a tapping guide to make sure the Easy Out is vertical
6) Mutter your favorite prayer/mystical incantation & turn the Easy Out counterclockwise. It should twist itself down into the screw thread and pop it loose.

Just a couple months ago, I ran into the same size screw with the socket stripped out in a Benelli Kite. I managed to find the Easy-Out, and popped the screw loose with no trouble.

If they really did use Locktite, the soldering iron dodge works well. Make sure you have really good hex keys (I like Bondhus).

Just in case, I also have left-handed drill bits. The heat from drilling will soften any threadlocker, and the left handed force & vibration can help to unscrew it before you have to completely drill it out.