Torx head scope base screws like .60 ea. $2.00 shipping no matter how many you get.
i put it i my favs.for your application,make sure you get the right thread pitch!
when you put the new screws in,put a tiny drop of clear finger nail polish on the threads.it acts as a thread locker that is easier to remove than thread locker.and you dont need to strong arm tighten them either.just tight is all.
I bought a few extra for spares. I got the torx head sockets. They won't cam out like the ones that came with my base. I mic'd the screws that came with my base and they were oversize in diameter. Double edge fuck up, cheap import screws and oversized, they cammed out 3/4 of the way in.
I also have loc-tite thread locker. A little drop will do ya' These pups are in inch lbs of torque. I have a small inch lb torque wrench and a T10 torx bit. Should work fine. I thought these were a good price also.
the measurement was off the top of my head of course,so dont hold it agin' me if it is wrong.and yes,those prices are fair.when i can afford it,i am gonna stock up on a bunch of stuff.
Guns Magazine, June, 2001 by Dave Anderson
12Next ..Long ago, some unknown gunsmith drilled and tapped a rifle receiver ring to attach a sight base. The machine screw size he chose was 6-48. Since then, the 6-48 base screw has become the industry standard.
Why this oddball size was chosen is a mystery. Custom gunmaker Ed Brown commented that if you went into a machine shop to buy a 6-48 tap, they wouldn't have it. The only purpose for which 6-48 screws are used is to attach sights to rifles.
A #6 screw has a diameter of 0.138". The second number denotes threads per inch (tpi), so a 6-48 screw is a #6 with 48 tpi. Industry standards for #6 screws are coarse (32 tpi), fine (40 tpi), and special (36 tpi). The 6-48 size is an oddball.
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Even the description of the Brownells Screw Chek'r (a device for identifying screw size) notes that it "covers all standard sizes, but not 6-48 or the other bastard sizes." Of course, Brownells supplies 6-48 taps and screws to the gunsmithing trade, and scope base manufacturers supply screws with their bases. It's not like we're going to run out. So what's the problem?
It used to be that heavy target scopes were mounted mostly on light-recoiling rifles. Powerful rifles either used iron sights or light 2 1/2x or 4x scopes -- and probably weren't fired often.
Today's shooters want light rifles, powerful cartridges, and bulky, heavy scopes. Keeping over 20 ounces of scope attached to a .338 Ultramag rifle is asking a lot of four small screws. Some gunmakers feel that the #6 size isn't adequate for current needs, and that 8-40 (0.164" diameter, 40 tpi) should become the new standard.
Ed Brown's custom 702 action comes drilled and tapped to accept 8-40 screws, as do other custom actions such as Nesika and Geske. Some custom gunmakers routinely convert factory actions to accept 8-40 screws by redrilling and retapping the holes. Brown believes it's only a matter of time before the major gun manufacturers switch to the larger screws.
What about the millions of rifles already out there? Properly attached, 6-48 screws do quite well. They are specially hardened and heat-treated, and they thread into the tough steel of the receiver. Most makers recommend they be tightened to 20 inch-lbs., which is not that easy to achieve with slotted or Allen-head screws.
Screws with Torx heads are easier to tighten. These come standard on some new bases, and are available from several base manufacturers and from Brownells. The bases, screws and receiver should be degreased with alcohol, and a thread-locking compound should be applied to the screws. Cinched up tight, they are adequately strong for most purposes.
For extra security with heavy scopes or powerful rifles, Brownells sells an 8-40 base conversion kit to assist gunsmiths in adapting factory actions. This is not a job for the home hobbyist. Drilling and tapping the tough steel of a receiver, while keeping the holes straight and aligned, is a task for a good machinist.