Got A Quick Question

[8uck5nort]

Not sure of the proper terminology here, but here is my question.

 

Is there a jig, store bought or home made, that can be used to increase the inside diameter of a bolt face rim(?) to fit a larger cartridge?

 

For example:

 

Let's say I wanted to convert a K31 Schmidt-Rubin bolt whose 7.5 cartricdge has a Rim diameter of 12.65 mm (0.498 in)and rebarrel for lets say .454 Casull which cartidge has a Rim diameter .512 in (13.0 mm). I do realize one is a rimless cartridge while the other is rimmed. The bolt rim would need material removed (roughly .35mm) to fit the larger cartridge. This will increase the sufacee area of the bolt face and in doing so need to be done without comprimising the bolt face thickness nor any possible heat treating of the bolt. I do not know if a bolt is heat treated to begin with. It would sound logical to assume it is since it is in contact with the case of the cartridge that contains the stuff that goes boom.

 

I was thinking of some kinda brass nail looking contraption which I would insert into the firing pin hole of the bolt and using a Felt wheel affixed (somehow to the nail) and using some kind of lapping compund to gently remove material from the inside diameter of the bolt/face rim... Okay you can laugh now.

 

What do you guys think? Do you know of something already out there so I don't go re-inventing the wheel here?

[sonic1]

can"t say i"ve seen one ...most bolts are put in a lathe and cut with a lathe bit to open them up..

sometimes hard to hold because of the bolt shape..mausers chuckup better with the bolt handle removed first..

also can be cut with an end mill,if you have access to one

[ken98k]

http://www.midwayusa.com/viewProduct/?productNumber=156264

[Doble Troble]

When I did my 376 Steyr AI on an M48 I opened the bolt face with a standard 1/2" 4-flute end mill. My plan was to open it up a bit more with a small fly cutter after, but it turned-out that the 1/2" mill was enough.

 

That bolt was hard - it's been a few years and I still remember the ordeal - it was slow going with a lot of lube (Tap-Eze and lots water out of a spray bottle - I'm a Bubba).

 

Grinding it bigger is probably a very feasable approach.

[donmarkey]

PTG makes the tooling, a block the threads in the action and a carbine cutter. Works like a lapping tool. Call Dave Kiff for details. It'll cost about $200 for a set though, so it'll be cheaper to send it out to be done. I charge $50 if I can cut the bolt handle off or $70 if you already replaced it. Bolt only more for extractor fitting.

Don