Machinist Question: What's Best Way To Reduce A .450" Forster Pilot To .447"?

[Liberty1776]

I need a Forster pilot to fit .45 Colt so I can trim the brass in the Forster Case Trimmer.

A #452 pilot is on indefinite backorder from Forster. No idea when it will arrive.

Midway had a #455 pilot and it arrived and is here on the bench. But it won't fit into sized .45 Colt, though. I assume the pilot is hardened.

I have a drill press, files, a Dremel and various stones for the Dremel (i.e., no lathe or mill).

A machinist question:

Idea #1 -- poor man's surface grinding

- Chuck the #455 pilot (published diameter is .450) in my drill press
- Insert a cylindrical grinding stone in the Dremel
- Turn on the drill press so the pilot spins
- Turn on the Dremel with its stone spinning
- Hold the Dremel vertically so the side of the stone is parallel to the pilot
- VERY CAREFULLY touch the spinning stone to the spinning pilot

Is that an acceptable way to get the #455 pilot from .450 to .447 (which is the published diameter of the Forster 452 pilot).

I need to remove .0015 to reduce diameter by .003, right?

https://www.forsterproducts.com/product/pilots-for-trimmers-case-inspectors-power/

Is there a better way to do it?

I don't think holding a fine file against the spinning pilot will work if it's hardened.

Times are truly dark when everybody -- including Forster -- is out of #452 Forster pilots. :wink:

[pworley1]

you should be correct

[ndnchf]

How about using it before sizing the brass? Or expand the brass after sizing.

[Der Gebirgsjager]

You're not talking about removing that much material. I'd try the file first. Measure often. Finish with some W&D paper on a flat surface, such as wrapped around the file.

DG

[CastingFool]

I think I would try a strip of fine emery cloth. Mike it first, apply the emery cloth for a few seconds, and mike again.

[M-Tecs]

Try a file first if too hard use abrasive paper on sanding block spinning it in the drill chuck or the Dremel. The hand held Dremel with an underdressed stone generally will not leave the finish you are looking for.

[Scrounge]

I think I would try a strip of fine emery cloth. Mike it first, apply the emery cloth for a few seconds, and mike again.

What he said! Fine emery cloth will not take off that much material at one time. Makes it easier to sneak up on what you want. If you had a mini-lathe, fine emery cloth would still be the best way to do it. Unless you have a very fine file, the only thing I'd use the file for would be backing for the emery cloth once you get close to where you want it, and to break the corner once you get the dimensions you want.

Bill

[country gent]

I would also recommend the fine emery cloth or wet dry paper. start in the fine side and work slowly checking often. .0015 on a side isnt much to take off. A small strip if soft flannel or cotton cloth backed by a fine file and some rouge flitz or simichrome will give a chrome like finish. Wrap around file so no loose edges to grab. A coiple drops of oil on the paper will help it cut cleaner.

As mentioned break sharp edges also polishing the lead angle makes a neater looking smoother pilot. A light 45 on the back shoulder helps it to get past small burrs from trimming.

[wilecoyote]

ok about chucking the pilot into the drill_
ok a flat file and some sanding paper to wrap flat around the file_
the sanding paper must be wet by oil, any oil, oil mixed w. water, wd40, singer oil... anything.
the oil will boost the work of the abrasive paper, washing away the particles that, whithout oil, would clog the grain of the paper.
oil will help to keep low the working temperature, even more at high speed_

[jim147]

If it stars getting hot let it cool before you mic it.

[Liberty1776]

Excellent suggestions, all.

After I posted it dawned on me that removing that small amount of material, I could probably hold an oiled flat knife-sharpening stone against the tiny bit of pilot metal.

But I'll try the oiled wet or dry paper, or emery, wrapped on a flat file. And mic often. Or do a fit check with sized brass. It's not heart surgery. I just want a pilot that fits.

That #455 pilot did not fit even fired (unsized) 45 Colt brass, by the way.

[wilecoyote]

you can use 2 flat files w. paper, each on the opposite side, balancing the pressure of both w. both your hands, so your drill press, if flimsy as mine, won't flex under one-side-only push. leather gloves welcome, of course.

[M-Tecs]

you can use 2 flat files w. paper, each on the opposite side, balancing the pressure of both w. both your hands, so your drill press, if flimsy as mine, won't flex under one-side-only push. leather gloves welcome, of course.

Never ever wear gloves around turning spindles. If the glove catches you will have serious problems. Watched a guy lose an arm when his glove caught.

[wilecoyote]

Never ever wear gloves around turning spindles. If the glove catches you will have serious problems. Watched a guy lose an arm when his glove caught.

I stand corrected, thanks.
maybe I should have explained myself better.
I refer to drill presses of somewhat reduced size, price, quality and power, like the one I use. this also assuming similar limits in the mechanical equipment by the OP.
side plays on mine are certainly excessive for true precision work, but I try to make do, although with a solution in this case already in itself unsafe and probably questionable.
approaching bare fingers to a little drill spindle holding a file, even wrapped in sandpaper, and oiled, or worse two of these, is certainly an improper and potentially risky activity. sturdy gloves saved me from nasty scratches due to involuntary contacts with some kind of improvised grinding tools, performing task like this.
hence my post, on which I share your observation, even more about operating more serious pieces of machinery.
(any your advise will be welcomed by someone, as me, with background such as to justify a nickname like mine.)
thanks again

[1hole]

A file is useless on anything case hardened; a file will slide over cased metal like glass. And a lathe won't do any better. Your cased expander will have to be ground down, not filed.

An improvised "grinding" system can be as simple as a postage stamp bit of medium grit carborundum paper glued to a popsicle stick and handheld at modest pressure against a rapidly spinning part. Your drill press will make a great spinner.

[rockrat]

If you have one of the diamond impregnated sharpening stone, that should work I would think.

[jim147]

Another option that just popped to mind is a machine I used to use all the time. Do you have an engine shop around you? The grinding wheel for valves can be set to do this with a constant flow of lubricant.

Not sure if they would stop to do a little one off but worth a shot.

[Liberty1776]

Well, I tried a fine-tooth file and indeed, the little pilot is case hardened. File totally ineffective.

Next I tried 400 grit wet/dry paper wrapped around the file. It polished it, but didn't really take any material off.

284985

I have a large selection of 2x72 sanding belts in all kinds of grits.
I tried progressively larger grits by hand-holding stiff belts against the pilot in the drill press, then realized I needed to move to my 2x72 belt sander.

I chucked the pilot into a battery drill.

284986
Spinning the pilot while running the belt sander

I spun the pilot against the running belt sander and finally got some sparks.

I stopped and checked with a sized .45 Colt shell until it fit. Then polished with a fine grit (220 or so; yeah, it could have been much finer, but it seemed to work.)

My grinding sort of angled the pilot a bit, so it's more of a slight cone now, instead of parallel sides, but it's the correct dimension where the brass meets the cutter, and the pilot centers the brass okay and allows successful trimming in the Forster Trimmer. This .45 brass is right at the limit of the cutter on the Forster. There is just enough of the cutter exposed to trim the brass. (500 S&W Mag would be bigger than the cutter diameter.)

284987

I trimmed my oddball .45 Colt brass to 1.106" (Schofield spec), then loaded some Lyman 452389 180gr button slugs into the brass using a set of Lee .45 Colt dies.

Unfortunately, the Lee Colt expander/powder-thru die didn't go short enough to work, so I used my Lee Universal Expander die to bell the mouths.

The Colt Sizer and Colt Seater/Crimper worked fine on the shorter brass.
I'd have tried a Lee Factory Crimp Die, but they are out of stock everywhere, so I seated and crimped with the one Seater/Crimp die. It closed the bell and seated to proper depth, so appears to work fine. They plunk fine in both my Lyman 45 Colt Case Checker and a revolver chamber.

And I'm not entirely sure the FCD would work on shortened brass.

284988
1.106" Schofield-length .45 Colt vs Normal Full Colt Case

Loaded them with WLP primers and 3.5 grains of Trail Boss.

Now for chronograph testing out of a Pietta Great Western II Single Action.

Lot of work to salvage some old brass, but fun, too. Why do we any of this reloading stuff, if not for fun?

[rondog]

People - as I read this, he's wanting to from LARGER to SMALLER! Maybe I'm reading this wrong, but going from larger to smaller is much tougher than smaller to larger......

[Liberty1776]

After all this, I discovered that the Redding pilots have the same 3/16" diameter shaft as the Forster, and Midway has them in stock. $7.99 for the .45 model.

[jim147]

After all this, I discovered that the Redding pilots have the same 3/16" diameter shaft as the Forster, and Midway has them in stock. $7.99 for the .45 model.

Story of my life.

[Baltimoreed]

My 1x42 inch bench belt sander is the most used tool in my shop.

[paul edward]

You could also crimp with a 45 Auto crimping die.

[Liberty1776]

My 1x42 inch bench belt sander is the most used tool in my shop.

After longing for a good belt sander for many years, I bit the bullet and bought the Shop Fox 2x72, 1 HP model. Like you, I use it almost daily for deburring, grinding and whatever. The quick-change belts allow rapid grit selection and it runs very stably and smoothly. A joy to use.

[Liberty1776]

You could also crimp with a 45 Auto crimping die.

Dang. Didn't think of that. Good idea.