Savage scope base screws 6-48 to 3.5mm fine thread

[griff383]

I recently pulled apart a Savage model 10 rifle to do some maintenance and remembered I had problems with one of the scope base screws on install. I thought I may have stripped the threads in the reciever but it turns out I may have stripped both screw and reciever threads. I brought two of the screws to my boss to see if he had a tap so I could run it through to fix the possibly damaged threads (he has every tool under the sun). He thought the threads were 3.5mm instead of 6-48. He ordered a tap (3.5mm) and some screws to fix it so those should be here on Monday.

If the threads in the reciever are damaged would the 3.5mm be a solution or do I have to go up to a size 8?

 

[Reloadron]

I am thinking that Savage receivers are factory 6-48. I would have used a 6-48 tap and chased the threads. Then see what you have. The next step would be to drill and tap for 8-40.

Years ago I was forever getting stripped out receivers after people messed them up. Brownells had the slickest tap and die set with slightly over sized taps, dies and a screw assortment in all the popular sizes.

<EDIT> I found the oversize set and it is only 6-48. About the most popular common size. </EDIT>

Anyway on a Savage receiver my guess would be 6-48 screws.

Ron

 

[griff383]

I just ordered a 6-48 bottom tap so will try that first.

 

[Reloadron]

Hopefully chasing the threads with that will do it for you.

Ron

 

[Zeke/PA]

3.5 mm is very close dimensionally to the diameter of a #6 screw.
If you have access to a screw pitch gauge, checking the actual thread pitch would help.
My guess is that the screws are 6x48 to start with.