So, how light can a Kimber Hunter be? A build thread.

[mtwarden]

If it’s fluted it would

 

[jpndave]

@jpndave @mtwarden would a Adirondack bolt work for pictures?

It should, I believe they are the same? Here are two 84m bolts, one with the longer extractor and the Coup de grâce showing the backside where the ejector rides. Notice how the track is cut out on the Coup de grâce. My thoughts are if they flute to just before the rear of the extractor and then after that take the track the ejector takes to the same depth as the minor diameter of the flutes, doglegged where it rotates to when closed with a gentle ramp in and out of the track, the bolt would function correctly and not have issues at least from the ejector floating up and down. Hopefully, that makes sense. The other question is how smooth the flutes would be riding over a magazine full of cartridges.



If you look at the 84m bolt in the middle you can see where the previous extractor rode and the new one behind it. There's ~ 1/2" difference.

 

[Wrangler13]

This is one of the new 6.5 cm. I have to grab a picture with the bolt out of the rifle. Karl bedded it, cut the barrel to 18”, added the 5/8x24 flare at the end, and fluted the bolt. Ti knob from Chris on the campfire. Carried it all season this year but never got a shot at a buck.

 

[packgoatguy]

I had a couple minutes this morning. For anyone who needs them, here are pics of a factory mountain ascent barrel and bolt.

Flutes on barrel begin 3 inches from the end of the action and are 8 inches long, about .22 inches wide. There are 3 flutes.
Barrel diameter at the muzzle end of the flutes is about .64 inches

There are also 3 flutes on the bolt. They extend about 2.675 long. About .335 inches wide, in a spiral.

 

[jpndave]

I had a couple minutes this morning. For anyone who needs them, here are pics of a factory mountain ascent barrel and bolt.

Flutes on barrel begin 3 inches from the end of the action and are 8 inches long, about .22 inches wide. There are 3 flutes.
Barrel diameter at the muzzle end of the flutes is about .64 inches

There are also 3 flutes on the bolt. They extend about 2.675 long. About .335 inches wide, in a spiral.

Any chance you can get a photo of the track the ejector takes?

Like these here. You can see where it is riding and rotating out on the Kimber on the left.

 

[jpndave]

Another thought, LRI has done group buys on their bolt fluting in the past. Would we have enough interest here to pull something like that off? I have at least half a dozen I could send in if need be. I also have a short and a long 8400. I suspect they will be much more willing to write a program for a dozen bolts than one and the setup time is less significant if they can run a batch.

 

[packgoatguy]

Any chance you can get a photo of the track the ejector takes?

Like these here. You can see where it is riding and rotating out on the Kimber on the left.

View attachment 664600

 

[packgoatguy]

Another thought, LRI has done group buys on their bolt fluting in the past. Would we have enough interest here to pull something like that off? I have at least half a dozen I could send in if need be. I also have a short and a long 8400. I suspect they will be much more willing to write a program for a dozen bolts than one and the setup time is less significant if they can run a batch.

LRI has a couple of my tikka bolts right now. Caleb their fluting guy said they wont do kimber bolts.

 

[mtwarden]

@packgoatguy - thanks for posting those!

@jpndave - I have two bolts I'd consider having done

 

[mtwarden]

LRI has a couple of my tikka bolts right now. Caleb their fluting guy said they wont do kimber bolts.

funny someone posted (maybe in this thread?) that LRI would/could do a Kimber bolt- hmmmm

 

[mtwarden]

@packgoatguy - anyway to approximate the depth on those barrel flutes?

Thanks!

 

[packgoatguy]

funny someone posted (maybe in this thread?) that LRI would/could do a Kimber bolt- hmmmm

I believe the poster had said that kampfield could flute a kimber bolt, not LRI.

 

[jpndave]

LRI has a couple of my tikka bolts right now. Caleb their fluting guy said they wont do kimber bolts.

Thanks for posting that pic. I wonder if that's just because of the hassle of setting it up or if there is some other reason? I may have to call in and see. Maybe they would reconsider if there were a dozen or more to do.

I may have to set up my mill to do it if we can't get someone else on board.

 

[packgoatguy]

@packgoatguy - anyway to approximate the depth on those barrel flutes?

Thanks!

Maybe 75 thousandths?

 

[jpndave]

Keep in mind that the weakest point in a barrel is ~6" forward of the chamber where the pressure peaks as the bullet hits that point (a little before that on fast powders and a little after on slow). The wall thickness vs pressure is most critical at that point so those flutes are compromising the barrel the most there. Further down the barrel as the bullet travels pressure drops and the wall thickness isn't as crucial. That's why Bartlein and others won't do the lightweight sporters in SS.

 

[Wrangler13]

Here are some pics of my kampfeld fluted bolt.

 

[mtwarden]

^ nice any issues at all, smooth?

Thanks

 

[ssimo]

How light can it be? Definitely too light

 

[Wrangler13]

^ nice any issues at all, smooth?

Thanks

Nice and smooth, same as my unfluted Montana’s.

 

[mtwarden]

^ thanks!