I'm doing some work on a No 1 Mk III* Lee Enfield, and looking for some good quality flat blade screwdrivers, as the screw slots are very narrow. Where can I get some good quality fine blade screwdrivers? Thanks.
Finding a set of good quality flat blade screw drivers is very difficult. I gave up on it a long time ago. Most of what is available today, are to soft.
The vast majority of screw drivers are made off shore in Asian plants. They make them up for industrial purposes as that is their largest market. The quality often leaves a lot to be desired.
I go to flea markets and garage sales to cherry pick the boxes of tools for screw drivers with decent steel and proper hardness as well as temper.
They are cheaper than anything I can find that is commercially available and last a long time.
I have stated this before, when it comes to flat blade screw drivers, I am absolutely anal about fit.
It isn't practical to have specific screw drivers for every size of slot. I have a couple that I don't change as they do fit several sizes. For the rest of the slots, very fine, narrow and wide, I will grind the blades to fit snugly and all of the way across the head of the screw/bolt. This almost eliminates slipping and galling. When a screw driver fits the screw head in a sloppy manner you can almost bet on a scratch from slipping or galling of the slot walls. When a screw driver blade is to narrow, galling can also occur. When a blade is to wide, you gall the inlet walls for the screw head.
Be really careful with that SMLE and its screws. They aren't making any more SMLEs and the screws have proprietary threads, as well as being darned expensive.
Stay away from offshore screwdrivers. Even some of the European makes leave a lot to be desired.
If you decide to go the flea market route stay away from the new in box offshore offerings as well. They are mostly garbage.
Look for the old beaters with wood or molded handles. Sometimes they look terrible. If you take a bit of time and have a bench grinder you can make up a set of screw drivers specifically for your SMLE. Be very careful not to pick the screw drivers that have hardened tips on their blades. They are not made for what you are doing. If you have to grind them to fit, that hardened tip will sometimes fall off.
I have a small tool box with a couple of dozen flea market/garage sale screw drivers of all different sizes. Some look like they were dug up in the back yard garden. The steel in them is perfect for your requirements.
By the way, if you are going to grind them to fit, be very careful not to overheat the blade tips and take the temper out of them. Grinding a blade until it is red hot and dipping it causes the tips to be brittle and they will break easily when you least need it to happen.
If you gall the screw slots with a properly fitting screw driver, you are over torqueing the screws.