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

[boltfluter]

Getting quite a few requests for this service lately. Considering offering it. What is your favorite method of doing this? Any and all methods considered and appreciated.

Thanks guys,

Paul

 

[GenePoole]

I've been meaning to try this too. I've got a couple of bolts from my personal F-Class guns with some pitting from primer blowby. I'm leaning toward drilling/reaming and soft-soldering as it just seems more permanent than threading, loctite, press-fit, etc. I figure I'll fixture it in the lathe with a 5C collet like I do for cleaning up lugs/face. That requires removing the bolt handle, but I'd like to replace the handles with PTG handles anyway (those will get silver-brazed).

 

[TAJ45]

Loctite not permanent enough?
When working elex motors for pulp paper plant use, 35 - 1000 hp, I would bore the end bell bearing area out to a sleeve spec, Loctite a new sleeve in then bore sleeve to bearing spec.
We did a LOT of these for pulp as well as power generating plants, all w a year warranty against defect/failure. NEVER a prob w sleeves failing.
Soldering may mentally seem to be superior, but personally doubt benefit other than being able to "mention" it when telling the Buds. The extra time has to be $$.

 

[Ggmac]

When I use to do it I threaded ( usually 1/4-28 ) used grade 5 or 8 bolts .
I've tried press ( hot -cold ) and lock tite , still think the thread is easier and can be easily redone if needed ( pitting )

 

[dolek]

Loctite not permanent enough?
When working elex motors for pulp paper plant use, 35 - 1000 hp, I would bore the end bell bearing area out to a sleeve spec, Loctite a new sleeve in then bore sleeve to bearing spec.
We did a LOT of these for pulp as well as power generating plants, all w a year warranty against defect/failure. NEVER a prob w sleeves failing.
Soldering may mentally seem to be superior, but personally doubt benefit other than being able to "mention" it when telling the Buds. The extra time has to be $$.

Now that is interesting, I wonder if the difference in forces would effect the integrity of the loctite bond ? No clue on this end,just curious .

I will give a shout out to Carlsbad here on the forum,whatever method he uses is a winner in my book. Happy customer here.

 

[TAJ45]

Integrity of bond? I've seen motors come in w the previous sleeve eaten through and still had to bore out remainder of the sleeve.....

 

[Dusty Stevens]

A good end mill in your lathe chuck cuts a nice square bottom hole, just sayin

 

[Alex Wheeler]

Heres how I do it.
Indicate the bolt body in 2 places. Get it running true.
plunge a 9/64 carbide end mill
plunge a piloted counter sink, its about .228 diameter about .050 deep
8-40 gun tap under power
chamfer the thread start or bore out a thread
square up and cut to size with a mini boring bar to fit the 8/40 screw head, use a slotted screw and make sure the slot cleans up ( dont sink the head too deep)
Install 3/8" long screw with red loctite
face with end mill in tool holder until slot is gone
center drill, drill with # drill just under reamer size, ream, in my case .062
cut remaining head flush to the rest of the face with boring bar
Turn firing pin to fit, make sure it bottoms out on its collar, or better yet order a run of pins to your specs.

The biggest issue with bushed pins I come across is care not taken to really get the bolt running true, the firing pin hole is now a source of firing pin drag because its not straight to the center of the bolt. Indicating a bolt in 2 places takes longer especially on a fluted bolt but I feel its necessary to do it right.

Hopefully you can make sense of that...

Jim Borden wrote an article as well, similar, but he uses a larger screw.
https://bordenrifles.com/wp-content/uploads/2015/12/firing_pin_bush.pdf

 

[dolek]

Integrity of bond? I've seen motors come in w the previous sleeve eaten through and still had to bore out remainder of the sleeve.....

I was asking about the different forces,not about your vast experience with sleeves. I guess you can't answer my question.

 

[TAJ45]

I was asking about the different forces,not about your vast experience with sleeves. I guess you can't answer my question.

There may not be an answer to your intended question of "difference in forces". What forces are you questioning? Lateral, centripetal, centrifugal?
It would seem rudimentarily obvious that a failed bearing of, say a 250 hp motor, under load, would exert not only "different" forces but tending toward extreme forces - besides heat.
So I ask again, could you be more specific re Extreme Forces.....

 

[Ledd Slinger]

Would it make sense, or are there any advantages to be had by bushing and reducing the firing pin diameter to .062" on a rifle shooting cartridges with Large Rifle Primers? Or is the .062" bushed FP only used with SRPs? Ive only ever experienced cratered primers in my SRP varmint rounds, but not sure if eliminating craters/gas leaks is the only advantage of a bushed/reduced dia FP? Thanks.

 

[Bc'z]

^^^^ I've wondered about the same thing.

 

[Dhahn]

^^^^ I've wondered about the same thing.

Hey gentlemen / women.

Look at this GEM manufactured by "Sinclair" it removes the carbon and sets the depth to SAAMI spec's. "Brownells" and other sporting supply's offer this Primer pocket uniformer. You can just purchase the tool as a stand a lone or purchase a holder that will give you more control when doing the cleaning by hand. The holder can also be chucked in a drill motor. I would not use it with a drill motor... don't ask me why.
This text below was copied and pasted.

The Sinclair primer pocket uniformers are precision ground from one solid piece of tungsten carbide, so there is no need to worry about changing the depth of cut. These cutters are designed to be used every time you reload. They cut the depth of primer pockets to the correct SAAMI specification and also clean the carbon out of the primer pocket after each firing. Available in 4 sizes: Large Rifle, Small Rifle/Pistol, Large Pistol, and a PPC/BR uniformer.

UP date.... Wow sorry guys, wrong info. I just noticed you are working on the firing pin hole. Sorry

 

[Ledd Slinger]

Hey gentlemen / women.

Look at this GEM manufactured by "Sinclair" it removes the carbon and sets the depth to SAAMI spec's. "Brownells" and other sporting supply's offer this Primer pocket uniformer. You can just purchase the tool as a stand a lone or purchase a holder that will give you more control when doing the cleaning by hand. The holder can also be chucked in a drill motor. I would not use it with a drill motor... don't ask me why.
This text below was copied and pasted.

The Sinclair primer pocket uniformers are precision ground from one solid piece of tungsten carbide, so there is no need to worry about changing the depth of cut. These cutters are designed to be used every time you reload. They cut the depth of primer pockets to the correct SAAMI specification and also clean the carbon out of the primer pocket after each firing. Available in 4 sizes: Large Rifle, Small Rifle/Pistol, Large Pistol, and a PPC/BR uniformer.

UP date.... Wow sorry guys, wrong info. I just noticed you are working on the firing pin hole. Sorry

Lol! I was really scratching my head the whole way through your post trying to figure out why you were talking about primer pockets until I read the "update" at the end. No worries

 

[Bc'z]

Hey gentlemen / women.

Look at this GEM manufactured by "Sinclair" it removes the carbon and sets the depth to SAAMI spec's. "Brownells" and other sporting supply's offer this Primer pocket uniformer. You can just purchase the tool as a stand a lone or purchase a holder that will give you more control when doing the cleaning by hand. The holder can also be chucked in a drill motor. I would not use it with a drill motor... don't ask me why.
This text below was copied and pasted.

The Sinclair primer pocket uniformers are precision ground from one solid piece of tungsten carbide, so there is no need to worry about changing the depth of cut. These cutters are designed to be used every time you reload. They cut the depth of primer pockets to the correct SAAMI specification and also clean the carbon out of the primer pocket after each firing. Available in 4 sizes: Large Rifle, Small Rifle/Pistol, Large Pistol, and a PPC/BR uniformer.

UP date.... Wow sorry guys, wrong info. I just noticed you are working on the firing pin hole. Sorry

Quality info for another current thread on main board.

 

[carlsbad]

I've been bushing quite a few lately that were previously bushed by others. Be careful what advice you take. --Jerry

 

[carlsbad]

Would it make sense, or are there any advantages to be had by bushing and reducing the firing pin diameter to .062" on a rifle shooting cartridges with Large Rifle Primers? Or is the .062" bushed FP only used with SRPs? Ive only ever experienced cratered primers in my SRP varmint rounds, but not sure if eliminating craters/gas leaks is the only advantage of a bushed/reduced dia FP? Thanks.

While it seems there are more problems with pierced primers with SRPs, you can get a lot of cratering with high pressure in LRPs too. I get Magnums in to bush from time to time. On my personal rifles, I shoot nothing that is larger than .070" and that is only because most customs come with .070. I sometimes bush them as well. Including my 338 LM.

As for other advantages, less energy is required to put a smaller diameter dent in a primer. This should result in more consistent ignition. That's the physics behind it but I don't have any test data to back it up.

--jerry

 

[boltfluter]

That's a good article written by Jim Borden. Food for thought. Keep the ideas coming. Thanks guys.

Paul

 

[Cloudrepair]

I have thread milled my savage bolt head to a 10-32 and counterbored it to a .0005 press for a 10-32 x.25 shoulder bolt instaled a
10-32x.25shoulder bolt with red threadlock then trued bolt head face with endmill and drilled and reamed to .063 in same setup dialed in tight with great results.
This sounded right first time

 

[Pawnee Bill]

My favorite way is to send the bolt to Greg Tannell.