|
|
Post by magnumwheelman on Jul 20, 2021 13:30:57 GMT -5
interestingly, it comes with both #6 & #8 screws... 8-40 screws to be exact... my Browning A Bolt I'm mounting a new scope to, is tapped for #6's... I bought a long range 3-30 X 1st focal plane Osprey & it's a biggun... the mount says use the 8-40's for "today's larger scopes" my local tool & fastener place had to special order me the 8-40 tap, apparently they are not common ... again, assuming on a 338 Winmag, that the #8 screws are substantially stronger than the #6's
... & that I should tap the holes in my receiver to 8-40... no negatives... right???
( the older Leupold base I had on the rifle, only used 3 of the 4 #6 screw holes in the receiver, & didn't have rings available for the 35 mm scope tube )
|
|
WARDOG
.30 Stingray
Retired.....mostly.
Posts: 199
|
Post by WARDOG on Jul 30, 2021 23:17:04 GMT -5
You're asking about negatives and screw strength?
The difference between a #6 and #8 is about .027" o.d. which doesn't sound like much, but it is. I'm surprised to learn that the Browning only uses #6's.
For a heavy Osprey on the magnum the #8 screws will be advantageous. However, do you have the proper equipment to enlarge the holes? A good vise to hold the action, a way of center finding the action so the new holes will be centered? Do you have a solid drill press or milling machine? Don't try to do the hole by eye with a Makita. Personally I would use a reamer to ream out the old threads. Drill bits can bite at the thread entrance and start a new hole off center. If you choose to use a drill bit, you will need the correct size. Don't round up or down to make the hardware store bit work. With 8-40 screws the threads are very fine so they will need a close tolerance hole. Hopefully the holes are through holes and not blind. If you tap the through hole be sure to deburr the inside of the hole before you reinsert the bolt. A poor quality 8-40 tap can easily break in the hole so use lube, take your time, don't force the tap and back off every 180* or less to break the thread chip before advancing.
There is a lot to know just to enlarge some simple holes. If you are not prepared, you will be happy you sought out a gunsmith or machinist to do the work.
|
|
