Round Type 99 bolt knob

[rcathey]

Perhaps it was soldered to achieve that nice flat butt-joint. Once cleaned up and refinished, the two different metal compositions colored differently thus showing us his impeccable work.

[jangle]

The only knob on "modern" Japanese rifles that is even close to this smaller shape is a Kokura 97 sniper, which is a little smaller in roundness than your standard egg shaped knob.
But it is not a Kokura 97 bolt either. Whoever did the modification did a very good job.

[Anzac15]

That's about the only explanation...if it is, it is an impressive piece of work.

[Rusty_Old_F250]

My guess would be everything but the knob itself is original steel. You could put the bolt in a 4 jaw chuck and center it so the handle spins on center, turn the original knob down to the diameter of the shank, and then slip a new knob on and silver solder it in place.

Whatever he did, he did a nice job! I’m not usually a fan of sportered arisakas, but this one is a handsome rifle!

Sam

[Doco overboard]

I'm building an amateur sporter 7.7 rifle now out of some dead parts from past endeavors.
I'm impressed by the way the knob was altered just because of the lack of being able to tell how it was done.
To me it looks like it was somehow manufactured that way from an amateur perspective but does have what looks like a lengthened handle section and has been been bent by having heat applied but not sure. I don't see any tool marks which are hard to hide and the grasping ball looks pretty round.
Hard to make an alteration without evidence of how it was worked from a beginners viewpoint. Interesting for sure.
Attachment 92352