Broken scope base screw

[Killroy]

That one looks like there's enough head left to saw a slot in it. I'd slit the top, hit it with some heat and get right on top of it with a perfect fitting screw driver and put my weight down and give it a twist. Heat being key.

 

[ELR LVR]

That one looks like there's enough head left to saw a slot in it. I'd slit the top, hit it with some heat and get right on top of it with a perfect fitting screw driver and put my weight down and give it a twist. Heat being key.

Good idea, I have found that also tapping with a punch or something on the offending screw can provide some extra wiggle space in the threads before trying to loosen
Some Kroil or ATF soaked in there while heating should also help

 

[JTEX]

Left handed drills often work well too. Heat then drill in,reverse....lots of times they come right put.

 

[Rat Rifle]

Left handed drills often work well too. Heat then drill in,reverse....lots of times they come right put.

^^^Bingo ! You’d make a good Millwright JTEX ! ^^^

 

[ArtinNC]

What is with that scope bases ? I bought a different brand and they are all using T#10 screws . And the star is not very deep in the screw and the T#10 leading edge strip off with 20# inch pounds . like they want you to have trouble .

 

[LVLAaron]

What is with that scope bases ? I bought a different brand and they are all using T#10 screws . And the star is not very deep in the screw and the T#10 leading edge strip off with 20# inch pounds . like they want you to have trouble .

Chinesium fasteners.

 

[SBS]

Done a bunch of them over the years. I'm not much on trying to get a broken screw out after it's been broken off, I just drill it out. I have fixtures that hold actions in line with the bed of the mill. Most modern actions have 2 base screws close together, 2 on the front ring and 2 on the rear bridge. Center perfectly on the nearby empty hole and move the appropriate distance to the broken off screw. Use a carbide center drill to start the hole; #3 for #6 screw and #4 for #8 screw. Go down slightly below the top surface of the receiver. Use a carbide tap drill of original size to drill screw out. Sometimes it will drive the broken part out on a through hole, sometimes not, so just drill through. On a blind hole over the barrel, just drill a little deeper, going all the way thru the broken screw. If you go slightly into the barrel thread -- doesn't hurt a thing -- quite a bit of metal here. If you're leary of the carbide drill breaking on the end as it hits the threads, you may want to use a coated HS drill. So clean the blind hole out a little at a time with proper size plug tap and MolyDee fluid, using air and finishing up with a bottom tap. Through holes are easier done with same fluid and a plug tap. If you don't like drilling slightly into the barrel on a blind hole, you can always pull the barrel. If you have only a single hole by itself (1 pc. bases on some older military actions, usually at the rear), use the carbide center drill again, but only to a very shallow depth, eyeball it and keep adjusting until you're sure it's in the center. If I'm unsure because its been already mangled up so badly that it's hard to tell, I then use a coated high speed tap drill which won't break if it has to give a little, unlike carbide drills. Usually these single holes are on the bridge which is usually fairly thin, which mitigates any serious damage to the threads. If you barely scrape the major dia. threads in the holes -- won't matter, they don't hold much. Never had a hole that was ruined this way, all would hold a base screw tightly again.

 

[AlNyhus]

What is with that scope bases ? I bought a different brand and they are all using T#10 screws . And the star is not very deep in the screw and the T#10 leading edge strip off with 20# inch pounds . like they want you to have trouble .

Art, I've seen some Torx Plus headed screws being used in bases. Make sure the bit you're using is compatable with the fasteners. A standard Torx bit will fit in a Torx Plus fastener but the fit will be sloppy and the edged will want to roll over....especially on the small T10's.

Just last week, I got a set of rings that have Torx Plus fasteners but the included wrench was a standard Torx.

Hope this helps. -Al

 

[ArtinNC]

So now we need a Torx plus Bit ??? but they don't make them . But I'm using the bit that come with the base screws . JUNK !!!

 

[AlNyhus]

So now we need a Torx plus Bit ???

Just if the screws are Torx Plus. Torx Plus bits won't work in standard Torx. The difference is pretty easy to see...assuming quality fasteners.

 

[LVLAaron]

side note... especially for small fasteners... get good tools like Wiha, Wera, something German.

 

[hoz53]

Just if the screws are Torx Plus. Torx Plus bits won't work in standard Torx. The difference is pretty easy to see...assuming quality fasteners.

i didnt know about torxplus Al— thanks—- i try to use t15 if i can instead of t10s— they break to easy for me and the bits dont hold up so well either.