Screw size info for you
- Thread starter crow#2
- Start date
Now you're thinking like a guy who wants to work on his own guns and do it the right way (no bubbaing)
I have one of these in both SAE and Metric. Have had them for many years. They are indispensable when working on old, odd or foreign firearms.
https://www.brownells.com/tools-cleaning/general-gunsmith-tools/gauges-measuring-tools/screw-chekr/
I have one of these in both SAE and Metric. Have had them for many years. They are indispensable when working on old, odd or foreign firearms.
https://www.brownells.com/tools-cleaning/general-gunsmith-tools/gauges-measuring-tools/screw-chekr/
loaded round
Hunter
The Brownell's Screw Chek'r works perfectly and is a great tool. I've also had mine for over 10 years and it's been a lifesaver more than several times when I've had to replace a lost screw.
It makes things a lot easier when you have a screw or screws that you don't know the size. Way back when, gun makers used some (my opinion) really odd size screws. But they probably weren't odd sized for them. Then as time went on, sizes and threads were standardized (think SAE and such) so it made things easier.
Acorn
Hunter
What do you do if you have a tapped hole but no screw to fit it.
If you have a tap and die set, estimate the size and try putting the tap in it to see it if fits or not. And there are also thread gauges that are made for very small holes to find the size.
Google "Small hole thread gauge" and you'll find them, Amazon has a bunch of different sets/styles
This set ^^^^ has both standard and metric gauges
Last edited:
NikA
Hunter
My method would be to use pin gages to determine the approximate minor diameter and thread pitch gages to determine the pitch. Should be able to work out the correct thread dimensions from there. But then again I have 2+ drawers dedicated to thread measuring and cutting.
Screw checkers are a fine entry level tool but don't cover nearly enough cases to be useful for a pro encountering diverse thread types. They'd be most useful to sort a large number of screws of a limited number of known sizes.
Screw checkers are a fine entry level tool but don't cover nearly enough cases to be useful for a pro encountering diverse thread types. They'd be most useful to sort a large number of screws of a limited number of known sizes.
There are screw sizes and there are thread pitch variations. Common screws for firearms are 6-48. I have seen 6-40, 8-32, 8-40, 5-40. I've even see 1/4-20, and 1/4-28. I have seen a whole passel of metric sizes too.
I have walked into the local Mac's with all sorts of assemblies, large and small, and headed right to the screw aisle.
