Opening bolt faces

[Ovenpaa]

A recent job was to open the bolt face of a .223 Tikka T3 to suit the 308 cartridge, the T3 is always a nice bolt to machine and I use a stubby solid carbide micro boring bar so no chatter. This one clocked in with no discernible movement on a 0,01mm lever dial indicator so I was happy. It is one of those jobs where it takes as long to clock the job in as do the machining and I used a .308 Go-Gauge to confirm the fit. Probably the hardest part was fitting the extractor back in place as they either go in first time or you faff around for ages. Luckily having a second pair of hands in the form of the Viking makes life easier. I am always surprised at how many bolts we receive for such work as it is not a particularly difficult job, it just needs some care.

[WelshShooter]

Looks very shiny and smooth!

[flamoudi]

That's all new learning to me. Very interesting....

Could my Barnard S action bolt be converted to take a 6.5 lapua? That done I rebarrel and save a fortune mebe?

Be kind if I got it wrong I'm no machinist or gunsmith.

[Ovenpaa]

That's all new learning to me. Very interesting....

Could my Barnard S action bolt be converted to take a 6.5 lapua? That done I rebarrel and save a fortune mebe?

Be kind if I got it wrong I'm no machinist or gunsmith.

is it a .223 bolt face? If so yes it is easily done, if it is a .308 bolt face it is already capable of accepting the 6,5x47 Lapua cartridge :)

..and yes it would save a lot of money as you are not investing in a new bolt or rifle action.

[Alpha1]

Interesting this kinda stuff facinates me. Would I attempt it myself. I wouldnt dare.

[Ovenpaa]

Dave, this is with exactly the same solid carbide cutters as I sent up to you :)

[Alpha1]

Ah I get it. I was actually using the ones you gave me over the weekend. They work a treat.

Question for you how would you go about milling a square hole in the end of a piece of 20mm aluminium round bar 10mm width and about 12mm deep. I might also need to do it in a piece of 20mm stainless. I have searched youtube and can not find any thing that helps. I don't want to rush into it in case I get it wrong I need to do 35 of them.

[Ovenpaa]

Square hole? Do you mean without radius's in the corners?

[Alpha1]

They can have radius's in the corners but they need to be tight they are going to be sitting on a valve stem. They need to be a snug fit. The other end of the job has an indicator on it to show the valves position.When the valve turns it moves the spindle and indicates the valve position. The drawing was wrong we had 35 of them made at £10 each.

[Ovenpaa]

Dave, I would need to see a drawing to better understand the job. I assume you will need to make a fixture, then drill a pilot and square it off, then move to a smaller slot mill to finish it off however that is a wild guess without knowing more about the job.