Info needed on re-pinning Remington RB action

[bufflernickl]

I have an original Remington rolling block action with a .45-70 barrel; I've no idea what the original cartridge/caliber was, but I'm told that it is a military action.
 
The pins and holes that the block and hammer pivot on are a bit sloppy, that is, you can feel minute movement if you twist and push them just right. I'm sure this can't be good for the action or the shooting. Recognizing that there are gunsmiths who do this sort of work well, still, I want to have a go at it myself. I have a lathe and mill available and can use them well.
 
At first I thought just to ream out the holes a bit and turn up new pins from drill rod, but having put some thought into the requirememts, I realize that the parts and their respective holes will have to be align-bored to do the job right. That is, the block, e.g. will have to be jigged into its correct location and the receiver and block bored simultaneously. Otherwise, the hole centers might (would likely) be somewhat off location. I also recognize the problem of getting those new holes in the original correct positions.
 
Does anyone know a website that has information on this process, or better, has a picture of the fixture used to hold parts? I've invented one mentally, but would like to see what others use.
 
TIA/buffler

[John Traveler]

Buffler,

I've used the method described by the late, great Frank De Haas ("Mr. Single Shot") to refurbish Rolling Block pins/actions.

1.  Install block and clamp frame in place on drill press table.

2.  Turn up slip-fit pins from cold rolled rod, and split them almost completely lengthwise.  Spread split slightly, and use it in a drill press with fine Clover valve-lapping compound to lap out the block and frame holes simultaneously.  Use regular up-and-down motion to make the holes uniform.  A couple minutes each hole is enough.  Repeat for the hammer pin holes.

3.  Turn oversize pins from tool steel rod, and using the same method, lap the pins to a perfect fit.  Spin polish.  Heat treat (harden and draw) pins before use.

Reaming likely removes too much material, but you certainly can do that if you wish.  I've no doubt that the factory used fixtures to originally drill and ream the holes in alignment, but that is not needed to properly fit tighter pins.

HTH
John

[bufflernickl]

Thanks, John, sounds like a winner. I'm a bit perplexed as to how you get the oversize pins in the newly lapped holes to do the final lapping, but if it takes turning two sets of pins, that's not much work, especially if the results are good

Cheers/buffler

 

[John Traveler]

Buffler,

There should only be 0.001" diameter difference between the "lap" pins and the "finish" pins.  

True, it's a tight fit at first (actually a light "press" fit), but the second lapping will give you a perfect "slip" fit..

Only the breech block and hammer need to pivot on the pins.  The pins can remain a "press" fit on the frame.

HTH
John

[bufflernickl]

got it!!! I'll likely make two identical sets of pins; finish and HT the "users" and leave the lap pins soft. Take out .001" with the soft ones.

I'm an amateur telescope maker and have grit from 3 micron up to 40 grit (small gravel:-) Any idea what grit tht Fine Clover is? I'd reckon about 400 or 600, eh?

Cheers/buffler