Sear spring mortise........HOW?
 

I took my .30 Luger 'shooter's' sear spring out to look at how they slotted the receiver. Ever looked at that thing? I can't imagine how they machined it. I'm guessing they used some kind of Woodruff cutter, but where could one get something that small today? BTW, if you guys ever need to make very small flat springs, old band saw blades work well. I needed to make a very small sear spring. I Dremel a piece, gently grind off the teeth..cooling often....and cut small springs out on the band saw......going very slow.

Sounds like a lot of work to me. I still have some original sear springs in stock. TH

The method used to create the sear spring mortise in the upper receiver has always made me wonder too... obtaining tools that small would not be an issue, but the obtaining the correct internal shapes and surfaces to that mortise are a machining operation that escapes my gunsmith and hobby machinist mentality...

All I know for certain is that the Germans and the Swiss did it MILLIONS of time... and it was perfect every time... An engineering miracle IMHO.

Even the Stainless Steel guns that were produced under several marketing names by the same manufacturer never produced this mortise to the same perfection as the original guns.

The company I ordered my dovetail cutter from, Harvey Tool, sent me their catalog...Idly browsing through it, I noticed they have very small Woodruff keyseat cutters... :eek:

I too need to cut a small "T" slot...I'll be ordering one of these cutters shortly... ;)

www.harveytool.com

Necessity....
 

What a Mother! Having little in the way of exotic equipment, I had to figure out how to mill this little slot. Took a small..3/32(?) broken end mill, ground the broken part off, slowly (Boy, is that thing hard!). Chucked it in the lathe and with a Dremel reinforced cut-off wheel, I ground it into a tiny cutter. Put my 'cutter' in my flex shaft Dremel and Voila', cut the slot I needed. Works just fine for a little sear spring slot.