These days anytime I start to mod one of the 22x guns I drill and tap the hole out bigger usually 6/40, but did the 5/48 for awhile. Then I put the new screw, I am using, in a drill and hold a file to it to make the head the right size for the breech I am using.
Man, Biohazardman, this suggestion was one of the best/most awesomest/most practical suggestions that I would
never have thought of on my own. Again, this was so simple, I applaud you. This is exactly where I am going to go with this problem.
I have only been into 2240 modding for 5 months and am using one of the Chinese 2240 to PCP conversions from "free_outdoor". The picture above of the screws is the stock screw on the bottom and my modified screw on the top. The head on the OEM screw was really small and dropped way into the breech and everything got caught into it, With your suggestion, I was able to just cruise into my local Ace Hardware and make the issue MUCH better.
I chucked the screw up into a Dremel tool, which had a bit "softer" squeeze on the screw, plus you can run it at 20K RPM if you want.
Here is a picture of the "chasm" that was the original drop, where everything would get stuck into it.
Here is a picture of the newly modified breech screw installed
There is still a "catch" in there that is either the bump of the difference in the depth of the screw versus the breech, or it may be getting stuck in the hex head now, but I am still getting snagging. It isn't NEARLY as bad as it was, but I still don't think that there is ever going to be a time that I can use the GravMag system I bought without gnarling a significant number of the pellets that make it in. So, my plan is to get some Torx screws and grind them down to the proper size. I'll get the widest head I can to get the most depth correction once they are ground down as I still need 0.02" or so of thickness at least to make up the gap. If I still get snagging issues, I'll just fill it all with wax, smooth it out and see what happens, but at least with a Torx screw it should always be able to be removed. It would be fun to be able to use my magazine.
Again, I REALLY appreciate your suggestion of grinding the head of a screw down to make it make up for the difference in the depth of the countersink for that hole. That was brilliant!
I hope the 10x's are in your future!
-Jonathan