hole in buffer bolt

Jason · Post by **Jason** » Tue Apr 19, 2005 2:34 pm

OK, how do i drill the hole in the buffer bolt for the firing pin

cobalt bit wont even make a mark. any ideas are welcome (bubba style ideas as I have no access to any milling equipment)

Abwehr · Post by **Abwehr** » Tue Apr 19, 2005 4:59 pm

I have not done this, but I have been told that once you break thru the case hardening, you can drill thru the piece. I have planned to use a carbide burr to get thru the first .020-.030 of the hard part, then drill until I hit the hard part on the opposite end. Then take the burr and CAREFULLY try to break thru to the hole. Then use the carbide drill to clean-up the hole.

Does this make sense on how to get thru the part?

Post by **TOM R** » Tue Apr 19, 2005 5:17 pm

when you figure this out

Post by **drooling idiot** » Tue Apr 19, 2005 5:51 pm

be more specific
buffer bolt PN# 99
striker PN# 67
or feed arm stud PN# 68 ?

most builds delete the buffer bolt and leave the firing pin unsupported.
the striker can be drilled with a certain type of bit , I'll look up if thats what you need.
the feed arm gets marked inside the rear circle of the bolt and then removed and cut in 3 pieces , the upper and lower get welded back in to hold the ejector "button" , leaving an open center for the firing pin.

Jason · Post by **Jason** » Tue Apr 19, 2005 9:03 pm

my bad, I should have explained better

I was talking about the bolt that holds the buffer spring into the buffer.

the way I understand it you have to drill a hole in this bolt to allow room for the part of the firing pin that sticks out the back of the bolt body.

Abwehr · Post by **Abwehr** » Wed Apr 20, 2005 7:08 am

Guys,

I was talking about the Item No. 67. This part needs a holed drilled fro the firing pin on my gun. I have a couple of spares, but have not drilled them yet for the firing pin. I did start to drill it and it is HARD! The cobalt drill bit would not bite and I could not start with a punch. This is when I deceided that a carbide burr to break thru the surface hardness would be required. Once broken thru, it shoulod drill fine.

I have just not had the time to complete the part yet!

huntsinmtns · Post by **huntsinmtns** » Wed Apr 20, 2005 11:53 am

Jason,
If you use a carbide bit you can do it very easily in vise and step up your drill size so you don't have to dremel so much, make sure you lead on this due to fp has side movement. I will get pic shortly and send to Steve so he can post it, Ihave not figuered out my camera.

The piece in back of bolt carrier ( feedstud) needs carbide to get thru, same as the striker fully hardned as far as I can tell.

Post by **salt6** » Wed Apr 20, 2005 4:41 pm

Here they are....

Jason · Post by **Jason** » Wed Apr 20, 2005 6:12 pm

thanks, I'll give it a go.

ak47dennis · Post by **ak47dennis** » Wed Apr 20, 2005 10:49 pm

Guys I used a lathe and a tungsten carbide bit and plenty of tap magic oil.
It is very hard but once you get thru the case hardening you’ll be fine.