Can you accurately measure the ID of a redding bushing....to .0005".... with a top of the line caliper, like a Starrett or Mitutoyo, or do you need a special tool? Using calipers, NONE of my bushing are within .0015"......they are all UNDERSIZED! On the other hand, my Wilson bushings are ALL within .0005"- .001".
Redding Bushing Diameters
- Thread starter PMA3
- Start date
As mentioned above a pin guage set is the most accurate way to measure the id of a bushing. Also it's fairly common to see variations in the id of Redding bushings. If you want a high quality bushing with correct dimensions I highly recommend the neck bushings that Whidden Gunworks produce. www.whiddengunworks.com
Ned Ludd
Silver $$ Contributor
How does the sized neck O.D. of your cases compare when using the bushings from either manufacturer? If the measurements do not mirror your caliper measurements of the bushings, it should be obvious which one was off. I have a fair number of Redding bushings and they give me the neck O.D. that measures exactly as advertised based on the bushing size to within .0005", which is at the limit of readability of the calipers anyhow. Never tried to measure the inside of the bushing, just checked to make sure they're giving me what I expect on the neck O.D. If your bushings from the two manufacturers are really that different, one of them should be giving you a noticeably different neck O.D. reading than the other after sizing.
I've measured my Redding bushings ID with calipers and mine also run undersized. More pertinent is that the ID of the bushing is not necessarily the ID you will obtain on your final sized brass neck OD. Variations in brass hardness as well as the total amount of sizing taking place from fired to bushing size can cause the brass to be smaller than the bushing ID that sized it. For example, my 308 bushing is a .337, measures around .3365 on the ID but I get an actual sized brass OD of .336.
I've just moved to measuring the net results on the brass and adjusting bushing choice based on that.
I've just moved to measuring the net results on the brass and adjusting bushing choice based on that.
Before there were dial and digital calipers there were vernier calipers. They were called "very nears" for good reason.
You can measure a 1" or larger inside diameters with some accuracy if your inside jaws are good. They are never very trustworthy for smaller diameters.
With many cheap 6" calipers the inside jaws are nearly worthless. Bushings are best measured with gage pins or you can simply size a case and measure the resulting case neck for a truly functional measurement.
You can measure a 1" or larger inside diameters with some accuracy if your inside jaws are good. They are never very trustworthy for smaller diameters.
With many cheap 6" calipers the inside jaws are nearly worthless. Bushings are best measured with gage pins or you can simply size a case and measure the resulting case neck for a truly functional measurement.
All calipers with internal measuring jaws have a small flat on the measuring surface, not a true knife edge.
This gives a false small reading.
As mentioned, gage pins are a good alternative as are small hole gages.
Small hole gages will be more accurate once you develop the feel needed to use them.
This gives a false small reading.
As mentioned, gage pins are a good alternative as are small hole gages.
Small hole gages will be more accurate once you develop the feel needed to use them.
Agree. The bushing does not size the neck to a specific diameter. The hardness and springback of the brass and the bushing all determine the final dimension. Just measure the neck o.d. before and after seating a bullet to get the tension you want.
Lone Hunter
Silver $$ Contributor
Agree with Webster and others on this. I would measure neck o.d. before and after to get the tension you want.
jepp2
Gold $$ Contributor
I have a set of minus pin gages and have checked many Redding bushings. You can depend the pin gage at the stamped diameter will NOT pass but the next one lower will pass. Every time I have checked.
But as others have mentioned, I spend more focus on the sized neck OD after passing through a specific bushing. Lots of things will affect that, but that is the ultimate goal, to have a neck OD that provides the neck tension you desire.
But as others have mentioned, I spend more focus on the sized neck OD after passing through a specific bushing. Lots of things will affect that, but that is the ultimate goal, to have a neck OD that provides the neck tension you desire.
Brians356
Silver $$ Contributor
When I pin gage them, I read from both ends. The amount of taper varies, and I'm not sure it's by design, but I'm sure you'll assure me it is. Also, the TiN ones usually run slightly smaller than the plain ones, but even the latter can be smaller than nominal.
-
Thank you all for the useful information. Sometimes the figures taken individually do not add up to the real world results. Seems the "trial & error" procedure still is the best way to solve a problem that doesn't make sense initially.
Paul
Phil
Gold $$ Contributor
butchlambert
Site $$ Sponsor
Brians356
Silver $$ Contributor
You're making this waaay too complicated, and you're not answering the OP's simple original question, to wit:
Can you accurately measure the ID of a redding bushing ... to .0005" ...
He did not ask how to decide which bushing will produce a desired neck tension, or the like.
-
butchlambert
Site $$ Sponsor
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.