Gunsmithing Are 8-40s and 6-48s interchangable?

[glock24]

I have a scope base that is counterbored for 8-40 Torx screws. I want to put it on a receiver that uses 6-48 threads.

Anyone know if the head diameter is the same on 8-40 (T15) and 6-48 (T10) Torx screws? If not, do I have any other options?

Thanks

 

[300sniper]

Re: Are 8-40s and 6-48s interchangable?

if the head sizes are the same as a standard socket head cap screw, like they probably are, they are different sizes. why not open up the receiver to 8-40?

 

[doc76251]

Re: Are 8-40s and 6-48s interchangable?

The 8-40 heads are a "touch" bigger than the 6-48 that's why it is counter bored. You can use the 6-48 in the 8-40 hole but it will not have the same strength as there is less screw head in contact with the base.

Conversely you could drill and tap the rifle for 8-40. I've done it with just the tap and good cutting oil.

Cheers,

Doc

 

[glock24]

Re: Are 8-40s and 6-48s interchangable?

Thanks guys, this info helps me with my decision.