What's your favorite way to bush firing pin hole?

[Nightraider]

Indicate bolt in two places
Drill .230" deep
Ream hole to specific diameter .250" deep
Use hardened ejector pin and press fit
Spot drill/ drill/ face/ ream
Gage pin new hole
Grind pin on surface grinder with Harig

 

[carlsbad]

Nightrider,
I find most of the bushing jobs I receive for rework were press fit. It appears that thousands of high g accelerations can eventually cause a pressed in bushing to move.

Of course I'm sure it can be made to work.

--Jerry

 

[swd]

The ones I’ve seen that were soft soldered or pressed failed. Threads are by far the best method.

 

[boltman223]

Indicate bolt in two places
Drill .230" deep
Ream hole to specific diameter .250" deep
Use hardened ejector pin and press fit
Spot drill/ drill/ face/ ream
Gage pin new hole
Grind pin on surface grinder with Harig

How are you holding the bolt to be able to dial it in in two places?

 

[Nightraider]

How are you holding the bolt to be able to dial it in in two places?

I follow Bordens instructions

 

[Nightraider]

Nightrider,
I find most of the bushing jobs I receive for rework were press fit. It appears that thousands of high g accelerations can eventually cause a pressed in bushing to move.

Of course I'm sure it can be made to work.

--Jerry

You're correct, but most aren't made with an ejector pin. When testing the insert, we blew a Raptor(think howa) apart, the insert wasn't phased. I have one in my trainer that has about 18k rds on it without issues. I think and what I've seen is the seating of the insert is what matters the most. My reamer creates a 90° pocket, when that pin is set the only way it can move back is if the bolt is destroyed. I did one with a grade 8 bolt that I pressed in and the pin was recessed by 10k rounds.

 

[boltman223]

I follow Bordens instructions

You use the labounty to hold the bolt then? Just to see if i understand this, you are counting on the chuck and the labounty fixture to hold the whole bolt true to the one spot you dialed it in then? I suppose if you're only going .575 deep its close enough?

 

[carlsbad]

You use the labounty to hold the bolt then? Just to see if i understand this, you are counting on the chuck and the labounty fixture to hold the whole bolt true to the one spot you dialed it in then? I suppose if you're only going .575 deep its close enough.

Close enough is not close enough. You do not want to change the face to be skewed from perpendicular to the boltway. If you use a La bounty, you need to be able to get it true in 3 dimensions. To confirm that, use a long mandrel and confirm it runs true in 2 places 3" apart. --Jerry

 

[boltman223]

Close enough is not close enough. You do not want to change the face to be skewed from perpendicular to the boltway. If you use a La bounty, you need to be able to get it true in 3 dimensions. To confirm that, use a long mandrel and confirm it runs true in 2 places 3" apart. --Jerry

Yeah, i couldn't agree with you more, thats my concern. With the labounty I'm not sure how people are doing that.

Use a mandrel? Like put it in the fixture, check it, take the mandrel out and put the bolt back in?

 

[Nightraider]

You use the labounty to hold the bolt then? Just to see if i understand this, you are counting on the chuck and the labounty fixture to hold the whole bolt true to the one spot you dialed it in then? I suppose if you're only going .575 deep its close enough?

I use two chucks and indicate directly behind the lugs and directly ahead of the handle.

 

[Rich S]

I made something similar to what others on here have used. I use a small stub on the back end. The bolt extends out far enough to indicate in 2 locations. Machining operations are light enough that the bolt is adequately supported. My 1st attempt, I could not extend the bolt far enough to indicate it in as well. I modifed based on recommendation from members on this site. I use the same fixture to true actions.

 

[boltman223]

I use two chucks and indicate directly behind the lugs and directly ahead of the handle.

Two chucks? Interesting. Can you post a picture of that?

 

[Bamban]

Two chucks? Interesting. Can you post a picture of that?

Not Nightraider, here is a rookie rendition of 2 chuck set up. You can touch up the back of the lugs in this set up, or wait till the steady is set up. With the steady in place, the bolt face is ready for any work.

The mini spider on the rotating TS chuck allows the bolt behind the lugs to be dialed in, the 6 inch 6J set thru clamped down on ball turned 1/2 x 13 bolt hex head dials the area forward of the handle. The ball head allows the workpiece to gimbal.

Not my original, built on Mike Bryant's set up when I visited him to school me on how to work on 700 receivers.

 

[Alex Wheeler]

Direct measurements are the way to go. Bamban's type of setup is about as good as it get for truing lugs.

 

[Will Henry]

Large rifle primers can blank too. I bushed one of my Model 70's when I ran into blanking issues. Bushed and turned pin to .062. The bushing was pressed in and loc-tited and has been in use for 23 years and three barrels. WH

 

[boltfluter]

Thanks for all the replies and great ideas, some real thinkers, on my favorite forum.

Paul

 

[Alex Wheeler]

Are you doing this service now Paul?

 

[boltfluter]

Are you doing this service now Paul?

Alex,

Still in the planning stages. I did manage to get a bolt to section in half to make sure when I do, it it is done correctly.

Paul

 

[Dusty Stevens]

Alex,

Still in the planning stages. I did manage to get a bolt to section in half to make sure when I do, it it is done correctly.

Paul

You can remove the bolt head from the body if you wanted to section one. You can see the solder line if you look real close. We used to take them off and install savage bolt heads. What fun.