Forster case trimmer pilot diameters

Pistolero

Well-Known Member
I will be making a few new pilots for my Forster case trimmer. I wonder if anyone
has a .224, 7mm, 8mm and .358 caliber pilots handy to measure the diameter of
the large part of the pilot?

Based on one that I have, I am estimating standard jacketed bullet diameter minus
0.005 should be about right, but if folks have them handy to get the correct diameter
one one, or a few, that would be helpful.

I think I can fake it if necessary, but other folks may have this info readily available.

Thanks.

Bill
 

Rick

Moderator
Staff member
Eating dinner right now but I should have the 22, 7 & 35. I know I don't have the 8. Will check in a bit.
 

Ian

Well-Known Member
Eyeball must be on the mend, Bill, good to hear.

If I were making my own from scratch, and I have, I would make them larger than the originals. Basically, figure out if you're going to be trimming before or after sizing, measure your case neck IDs, and deduct perhaps .001" from that. You get a more square and cleaner cut the less slop there is.
 
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Rick

Moderator
Staff member
Ian is correct. I have both standard sizes and custom diameters for neck turned/NK sized brass. In addition Forster makes two distinct types of pilots, one for bottle neck cases and one for straight wall pistol cases. The 22 and 7 are bottle neck and my 35 is the other straight wall style.

Good news bad news. I do have the 22, 7 & 35. Bad news is . . . I ain't measuring nuttin until I can find a battery for my micrometer. Might have to order online. :( Also have the standard pilots in .243 and .277 and 308.
 

Pistolero

Well-Known Member
I have had trouble with them being too large, as I usually trim after sizing, and occasionally have
difficulty pulling the cutter and pilot out of the case due to tight fit and the newly created
burr. Can pull the pilot out of the cutter, a PITA. The extremely small out of square possible,
doesn't worry me. In my experience a few thousandths loose works better than too tight.
I want to know what the factory is, and will try one, and see if I want to deviate one way or
the other.

Eye is semifunctional, still cannot lift more than 20 lbs, no dust (can't mow, and need to,
no wood working) can't bend over at all, no shocks - (no shooting), and debris from the surgery stirs up
inside the front chamber if I move around much, vision goes from kinda OK to extremely cloudy, will
clear up with an hour of sitting still, like reading.
Beats being blind, but this is a long term fight, losing ground slowly but steadily, unfortunately.

Bill
 

Pistolero

Well-Known Member
Rick does not own an actual mechanical, micrometer.....:headscratch:

How will you reload 'after the fall"? ;)

Thanks, no rush.
 
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Rick

Moderator
Staff member
A mechanical mike would do me little good, cannot see the lines on one well enough to read it. :( Would need to set up a magnifying glass to use it. Need the reading glasses to see the digital. I've had this Mitutoyo for 25-30 years, first time I've ever had it fail and no backup battery. ;)
 

Ian

Well-Known Member
I gotta raise the question.....are we talking Forster-made trimming, or neck-turning pilots being too tight? I've found the trimming pilots to be frustratingly small. Sometimes the long, cylindrical turning pilots are too large, but they can be bought in specific sizes for some calibers.
 

Rick

Moderator
Staff member
I gotta raise the question.....are we talking Forster-made trimming, or neck-turning pilots being too tight? I've found the trimming pilots to be frustratingly small. Sometimes the long, cylindrical turning pilots are too large, but they can be bought in specific sizes for some calibers.
^^^^^^ This is correct, I didn't explain that well.

Length trim pilot.jpg neck turn pilot.jpg

The pilot on the left is the length trim pilot. The right picture is the outside neck turning pilot.
 

Brad

Administrator
Staff member
A mechanical mike would do me little good, cannot see the lines on one well enough to read it. :( Would need to set up a magnifying glass to use it. Need the reading glasses to see the digital. I've had this Mitutoyo for 25-30 years, first time I've ever had it fail and no backup battery. ;)
Probably an easy to find battery locally. Mine uses a 357 size I believe.
Look at numbers on battery and look online for equivalents.
 

Rick

Moderator
Staff member
Walgreen's has the best battery selection around here, last time maybe 2-3 years ago they were out of this one. Might have it now. This Mitutoyo is really easy on batteries, paper that came with it says it will last in a shop for 8 hours a day for a year. I don't of course use it nearly that much and it lasts for several years.
 

Pistolero

Well-Known Member
Length trim pilots. I've been using two of the Forsters for decades, happy with the stock one,
but took them out to the cabin with my other one, figured on making more, but did not remember
to measure them. I have a .30 cal one, .005 smaller than groove diam of .308.

I have the neck turner, but only used if a few times on 7x57, only one 7mm pilot for that rig.

This is the little hand crank lathe-like thing on the gold anodized base.

Often the watch section of Walmart has more batteries than you would expect. You have to
find someone at the jewelry/watch counter, PITA, but the usually have what I need.

Bill
 
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Rick

Moderator
Staff member
Well no wonder the battery is dead . . . I went and put a bunny battery in it. I've never gotten any battery life out of a bunny battery in anything, put one in a wall clock a few months ago and it lasted 2 days. Yes Brad, it's the 357/303. I'll see if I can find a copper top.
 

Rick

Moderator
Staff member
Well dang . . . Bought another bunny battery. :mad: They had the bunny batteries in a single pack for $6. They only had copper Tops in a 3 pack for $16. That's most likely how I ended up with a bunny battery in it. :(

Factory stock length trim pilots measure . . .

6mm .2732"
35 caliber .3541"
41 caliber .4058"
44 caliber .4248"
45 caliber .4473"

All have about a .001" taper to them.

All of my additional pilots are outside neck turning pilots.

22 caliber .2212"
6mm .2400"
27 caliber .2745"
7mm .2800"
30 caliber .3055"

All measurements powered by the bunny. :)
 

JSH

Active Member
Bill, my Forster trimmer has also served me well. I have swayed from my CB shooting some the past year and a half. I got started on 17's and 20's no adult supervision,lol. It would not take much of a push to get me over the edge and try a .14.

My trimmer troubles me with the burr that gets between the cutter and the pilot. I have tried trimming before and after sizing with no noticeable difference.
I know when I was messing with 22BR and 6BR years back I had no such issues. The only thing I did different was to run the neck over a sizing mandrel that probably trued them up some? Though I was using carbide button dies on both, no expander on decap pin.

Want to test ones nerves,eyes and patience? Neck turn some 17's
Jeff
 
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