A while ago I posted on here about the Browning Model 71 I had bought. It shoots fine and all, but I have decided to throw out the receiver peep in favor of a FastFire.
Since getting myself one of those Turnbull sights imported would be coupled with an immense financial investment, I'm trying to put together a CAD file so I can have one machined locally.
I've already taken all the measurements I need for the adapter plate and everything, but I still need the specifications on how far the mounting screws on the gun are apart.

The measurement I've taken from the inner edge of one hole to the outer edge of the other comes out at right around .4", the measurements from outer edge to outer edge come in at .5".
Does anyone here know the factory specifications or does anyone have a template for drilling&tapping receivers that might have the numbers?

Thanks!

I have that info at home and will relay it to you this evening if nobody comes along before then

My apologies, last night I wasn't able to find my records on these measurements in the mountain of reference material I have - so i broke out the calipers, a well used 71 and went to measuring/photographing. Once i was finished I posted the measurements and corresponding photos here and realized immediately afterward that I'd forgot to zero my calipers before starting - oops!

Anyhow, I'll repeat the process tonight with zeroed calipers and get it posted.

Wouldn’t one also need to know the exact location of the holes on the receiver?

https://www.turnbullrestoration.com/gun/fastfire-receiver-mount-model-1886-model-71/

Noted above.

"Since getting myself one of those Turnbull sights imported would be coupled with an immense financial investment, I'm trying to put together a CAD file so I can have one machined locally."

Yes, most definitely, I had that info as well (although it was wrong - ha).

Asking others to take measurements and your own ‘right around’ measurements seem to leave too much margin for error. I would just go with the original receiver peep that came on the gun.

^^^^ This. I don't understand asking when the necessary pieces (gun and receiver sight) to get the measurements are at hand.

Thanks for the help. I got a pair of digital calibers now and will try measuring later.