Splitting a barrel block

[Switchbarrel]

A buddy bought a rifle that has a round barrel block bedded to the stock.
It's a solid, round block. Pressing the barrel into the block is not conducive to changing very often.

We were talking and he'd like to have it cut in half and set up to be a clamp type block. While I still have one local lead to check with, it seems like most of our local machine shops don't want to do 1 piece jobs. In case it doesn't pan out, any ideas who I can lead him to that could split the block, mill some flats into it and then drill/tap 3-4 holes per side for clamping down the top?
What would a reasonable price be?

Due to the mounting set-up of this current block, re-doing the block seems like an easier option vs. buying a new split block and then having to re-do the stock.

Thank you.
-Rick

 

[mikegaiz]

I have done this and there is a problem. say your block is for a 1.45 heavy barrel, the boar diameter of a glue in is greater (filled by glue) , so if you split it it will not fit a 1.45 barrel, 1/2 the diameter will be like 1.65. when clamped in it will only contact top and bottom at the center of the 1.45 diameter. I had to use bedding to hold the barrel tight. I don't think the outcome was accurate enough. that is my opinion.

 

[noload]

I have a alum stock with the bottom block integrated with the stock, the top half is held with 8 or 10 SS allen head cap screws. I have bedded different contour barrels in the block system. I have done it several ways using Devcon titaium . I've concluded the best way to bed a barrel in the block is to do it in 2 stages bed barrel to bottom block first, then do top cap last. Doing the bedding in 1 step is a sleepless night. That said, I thing a machine shop could cut your block in half with a slitting saw in a mill. Pat

 

[Gundoktr]

You don't say what size the block and barrel are. Is there enough material between the OD and ID to fit clamp screws?

 

[Switchbarrel]

You don't say what size the block and barrel are. Is there enough material between the OD and ID to fit clamp screws?

Good question, not sure why I didn't think to include that info...

Barrel is 1.250" straight. The block is circular, 6" long and .424/.425" thick on each side. Thank you.


(his artwork )



-Rick

 

[mikegaiz]

This is mine after. it will work, if you use bedding to fit barrel.

 

[Gundoktr]

What material is the block? Steel or Aluminun? . How long is it? What is the diameter of the block and is it bored 1.250 for the barrel. I am not getting all the info needed for this project.

 

[Switchbarrel]

What material is the block? Steel or Aluminun?

Appears to be Stainless (def. not aluminum).

How long is it?

As stated above, 6" long

What is the diameter of the block and is it bored 1.250 for the barrel.

Both of these measurements are +/- .002 or so, best as I could get them. As I rotated around the block, they would change slightly as well.
Yes, the barrel that was in there was stated to be a 1.250 barrel. I don't have it in hand and my friend is out of town, can't measure it right now for exact dimension. There is some white material inside the block, whether it's some type of glue or rosin, I don't know. My friend had to use his hydraulic press to get the barrel out. I'm thinking one was heated and the other was frozen and the barrel pressed in originally...?

2.0945"

1.2415"

I am not getting all the info needed for this project.

Sorry, I'm trying.
-Rick

 

[dkhunt14]

Sounds to me like a glue in. We always used marine tech. You need to heat it and press them to get them out. I like a glue in over a clamp block. There is no stress on a glue in. If it is a glue in you have extra room for glue and it will be too big inside to split. A split block has to fit right or it will not take the recoil. I have seen split blocks shoot really good and then they take it out and put them back in and they don't shoot as good. Even torqueing the screws didn't help. That's why I don't like a clamp block. Calfee wrote an article in Precision shooting about a clamp on rimfire tuner and when you slugged the barrel it got tighter after the tuner was tightened to the barrel. If two little 4/40 screws close the bore, what happens when you use 6 or 8 1/4-20 or so bolts? We use a hole in the bottom near one end and force the glue in with a plastic syringe. We have recess on each end to hold an o ring. We remove the front o ring a little and squeeze the glue in to fill it. Then we clean the excess glue and push the O ring in. We also have set screws at 3, 6. 9. and 12 oclock at each end to center barrel and make sure it is straight in stock before gluing. After glue is dry we loosen or take the set screws out. Matt

 

[EWaugh]

Good reply. Thanks Matt, for sharing.

 

[dkhunt14]

We also clean the block and barrel with brake clean to make sure it bonds. The block is always rough from being bored with a boring bar. We turn a slight thread on the barrel in the block area. Not very deep and real coarse. It not a file and a few marks will work. You need something to help bond and hold so it doesn't fly out from recoil. Matt

 

[dbramley]

What about slitting it, drill and install clamping screws, then clamp it together and bore the center in the lathe to true up the hole. Maybe go .010 larger for glue? Would that make it easier to bed the barrel in the block but give enough room for stress free bedding?

Dan