Long Gage Pins

[Jud96]

So I had a thought, it might not be practical, of using 6" long gage pins to dial barrels in. The idea would be to dial in 3" of the barrel using the gage pin with 3" outside the barrel for indicating vs using a long reach indicator to dial in the throat. The range rods are easy to use, but aren't repeatable. The long reach Interapid is very repeatable, but it's not the easiest or fastest to use. I got the idea from using solid ground mandrels for indicating actions. These mandrels are in .0005 increments and they're very repeatable, and can be removed and reinserted and be within .0002-.0003 of what they were before being removed. I thought using long gage pins/mandrels in .0002 steps could speed up and make indicating barrels easier but not sacrifice precision. I also was looking at the Straight Shot Gunsmithing range rods that use x2 bushings 3" apart on a 7" overall length rod. The 2 bushings seem like they'd be more repeatable than just one, but there's still the slop between the rod and bushing and bushing and bore. Thoughts? Thank you

 

[LVLAaron]

Personally I don't like pins for the purpose. I found gordy rods to be repeatable, if you hang a little weight off of them to take up any slop in the set up.

I think you'll find the best results if you're working with the groove, not the bore (lands)

 

[gunsandgunsmithing]

Are you currently dialing in the lands or the grooves. I think most prefer grooves but I do think both ways can produce winning barrels. I'd lean toward the groove being of most significance, if for no other reason than it's roughly 80% of the bore.

 

[RussellJ]

So I had a thought, it might not be practical, of using 6" long gage pins to dial barrels in. The idea would be to dial in 3" of the barrel using the gage pin with 3" outside the barrel for indicating vs using a long reach indicator to dial in the throat. The range rods are easy to use, but aren't repeatable. The long reach Interapid is very repeatable, but it's not the easiest or fastest to use. I got the idea from using solid ground mandrels for indicating actions. These mandrels are in .0005 increments and they're very repeatable, and can be removed and reinserted and be within .0002-.0003 of what they were before being removed. I thought using long gage pins/mandrels in .0002 steps could speed up and make indicating barrels easier but not sacrifice precision. I also was looking at the Straight Shot Gunsmithing range rods that use x2 bushings 3" apart on a 7" overall length rod. The 2 bushings seem like they'd be more repeatable than just one, but there's still the slop between the rod and bushing and bushing and bore. Thoughts? Thank you

Vermont Gage offers Individual Long Pin Gages.
Up to 6" long, .1801" to .2810" diameters Class ZZ are $62.00/each
Up to 9" long, .1801" to .2810" diameters Class ZZ are $72.00/each

 

[Jud96]

Personally I don't like pins for the purpose. I found gordy rods to be repeatable, if you hang a little weight off of them to take up any slop in the set up.

I think you'll find the best results if you're working with the groove, not the bore (lands)

I have measured off the grooves with the Interapid. It’s just slow and not the easiest thing to do. I use tenths indicators everyday to dial in parts, check runout, inspect, etc but using the long reach inside the bore is tricky. I’ll get use to it eventually, but I feel the long gage pins would be interesting to try.

 

[LVLAaron]

You'll get used to it. I switched to the interapid, it was an adjustment, mainly because the dial goes the wrong way... but I can dial a barrel in maybe 5 minutes with it.

 

[Jud96]

Vermont Gage offers Individual Long Pin Gages.
Up to 6" long, .1801" to .2810" diameters Class ZZ are $62.00/each
Up to 9" long, .1801" to .2810" diameters Class ZZ are $72.00/each

Yeah I saw that. I’m getting some quotes from other sources as well. Looks like it would get very expensive to have a range of pins for each caliber

 

[Jud96]

You'll get used to it. I switched to the interapid, it was an adjustment, mainly because the dial goes the wrong way... but I can dial a barrel in maybe 5 minutes with it.

Yeah that’s fast. It took me an hour to dial the barrel in, when I usually take 5-10 mins with range rods. But I dislike range rods because they’re not repeatable.

 

[LVLAaron]

I load the barrel with 1.5 inches sticking out of the chuck... I'll indicate on the breech end and close to the chuck on the OUTSIDE of the barrel first... it's really quick that way to get things roughed in... then go to the bore and things aren't usually too far off.

 

[DaveTooley]

Yeah I saw that. I’m getting some quotes from other sources as well. Looks like it would get very expensive to have a range of pins for each caliber

If you use button rifled barrels you'd spend a LOT of money. I have and have used a .238" bushing on 6 MM barrels before. If I knew then what I know now I would have saved a lot of money buying bushings.

 

[Jud96]

If you use button rifled barrels you'd spend a LOT of money. I have and have used a .238" bushing on 6 MM barrels before. If I knew then what I know now I would have saved a lot of money buying bushings.

Most of the cut barrels I’ve inspected/used were all within .0002-.0004 of what they should be. I was thinking of having a nominal size ( ex. 0.237) with -.0004 and +.0004 in .0002 increments for a total of 5 pins per “set”. But with them being $75+ EACH, it doesn’t sound practical at all. A whole 25 piece set of Deltronic pin gages is $250-275. Just 5 of these will be $375. It was mainly just an idea I had that seemed like it would work.

 

[gunsandgunsmithing]

It's pretty amazing how much straighter and better centered most bbls are now than just a few years ago. Better drilling/reaming but I think most makers have gone to hones too, which can help as well. I've seen some pretty crooked bbls over the years but all the big makers are doing much straighter bbls now than even then. Sure makes it easier getting things dialed in is about all I'll say because I've alse seen some crooked bbls shoot as well as any bbl out there. We're blessed to have a plethora of great bbls but ABC Barrels are still the best I've ever seen. Hope they are back up and running soon.

 

[paperpuncher]

Here is an option to look at
SSG rods
Scroll down below the TBAS

 

[Jud96]

Here is an option to look at
SSG rods
Scroll down below the TBAS

Yeah I’ve looked at those. They show out of stock, and I called and emailed him but haven’t heard back. I’d like to get one to try one out. If he doesn’t offer them anymore, I could always get one made

 

[mikecockcroft]

Thinking the same as Aaron I made this to go in the tool post and one for the outboard to get roughed In quickly with thou indicators. Starting with a tenth indicator made my head spin and led to a drinking problem