Redding Type S bushing question

[Thumper580]

I have a Redding 332 bushing..... I would assume that means the ID is .332. However when I measure it with my dial indicator it reads .330. Off spec bushing?? Or does it mean the 332 would equal a loaded OD and it is machined to be .002 smaller. Wanted some clarification before I order more bushings. Thanks.

 

[mdmp5]

The margin of error on the Redding bushings is about .0005. I forgot if they undersize them or oversize them. I have had the conversation with them on the phone in the past. .002 is off. Check your calipers again. If you are getting the same reading, I would drop Redding a line.

 

[wirehand]

All of my Ti bushings ID measure .004 less than the size indicated on the bushing.
I think it would be safe to assume that this is what the neck would measure after running them thru, including the brass spring back.

 

[milo 2.0]

.332" should be the outside diameter of the neck, seated bullet should go .334". I'm not in agreement with thumper on .0005 tolerances, I've seen way worse. Before you order, seat a bullet and measure OD, then add .002", that should get you.

 

[No1]

If you mean you are measureing with a dial caliper you will not get a true ID reading especially on a part that small. You need bore gauge and micrometer. Without a bore gauge, best bet is to run a case in it and measure the neck after.

 

[Aeon1]

You are using the wrong measuring tool for the job. Standard dial calipers are typically not used for precision measurement of internal diameter holes especially small internal holes. The reason is simple, the measuring surfaces of your calipers are flat. Now how do you expect the flat surface to touch the outermost diameter of the surface of the ID you are trying to measure? It can't! If you would use a proper tool or precision pin guages I think you'd find your bushings are within .0005" of the stamped diameter.

 

[milo 2.0]

For the last 2 posters, he really needs to be measuring the od of the sized brass to come up with neck tension numbers. Measuring ID, the number should come in just under the diameter of the bullet used??

 

[Thumper580]

Thanks for the responses. I just want to be sure I'm ordering the correct size bushings. If a loaded round measures .330 then I need to order a 329 bushing for use in a bolt gun and not get hung up with the ID measurement of the bushing?

 

[milo 2.0]

Thanks for the responses. I just want to be sure I'm ordering the correct size bushings. If a loaded round measures .330 then I need to order a 329 bushing for use in a bolt gun and not get hung up with the ID measurement of the bushing?

Correct, but I'd go .328" for .002" tension, the more you shoot the brass, the more springback you'll get.

 

[Thumper580]

Correct, but I'd go .328" for .002" tension, the more you shoot the brass, the more springback you'll get.

Thanks....

 

[mdmp5]

You are using the wrong measuring tool for the job. Standard dial calipers are typically not used for precision measurement of internal diameter holes especially small internal holes. The reason is simple, the measuring surfaces of your calipers are flat. Now how do you expect the flat surface to touch the outermost diameter of the surface of the ID you are trying to measure? It can't! If you would use a proper tool or precision pin guages I think you'd find your bushings are within .0005" of the stamped diameter.

YESSSS!!! This is what I knew, but forgot about. Redding told me this on the phone a few years ago. The inner claws on a caliper will always read less than the actual internal diameter. There is still room in there, and only if you open the calipers forcibly against the inside of the bushing will you get close to the actual inside diameter. But I wouldn't do this, because there is no sense in possibly damaging your calipers. Just take Redding's measurements on the bushings as true, unless the OD of your sized necks are far out of spec. Just make sure you deburr before you size the necks or the edges will radius off the bushing and create a smaller OD.

 

[Aeon1]

For the last 2 posters, he really needs to be measuring the od of the sized brass to come up with neck tension numbers. Measuring ID, the number should come in just under the diameter of the bullet used??

The measurement that matters is the measurement of the neck OD with the case you intend to use with the bullet you intend to use seated in the case. Find the average OD of the neck (with seated bullet) and for most a bushing .002" to .003" smaller than the neck (with seated bullet) OD measuement will do just fine. If you don't anneal and as the brass work hardens the smaller bushing (like a .003") may be needed to keep effective neck tension consistent. Most will never notice this and will never need to use different neck bushings.

 

[milo 2.0]

The measurement that matters is the measurement of the neck OD with the case you intend to use with the bullet you intend to use seated in the case. Find the average OD of the neck (with seated bullet) and for most a bushing .002" to .003" smaller than the neck (with seated bullet) OD measuement will do just fine. If you don't anneal and as the brass work hardens the smaller bushing (like a .003") may be needed to keep effective neck tension consistent. Most will never notice this and will never need to use different neck bushings.

I thought that is what I was trying to convey to the op. Sized brass will usually measure .002" under that of a loaded round. If done correctly.

 

[blackfoot]

I can't remember if Redding bushing are this way, but if you put a Wilson bushing in upside down you'll get about 1/2 thousands smaller. Remember .002 neck tension is kind of the standard for precision single shot rifles, etc. You MAY need .003 in a magazine fed bolt gun, and you may have to adjust bushing sizes depending on the condition of the case neck, etc. You normally won't get away with just owning one bushing. Too many variables.

 

[Gary Smith]

Reddings are the same way, blackfoot spot on correct.

 

[mdmp5]

I can't remember if Redding bushing are this way, but if you put a Wilson bushing in upside down you'll get about 1/2 thousands smaller. Remember .002 neck tension is kind of the standard for precision single shot rifles, etc. You MAY need .003 in a magazine fed bolt gun, and you may have to adjust bushing sizes depending on the condition of the case neck, etc. You normally won't get away with just owning one bushing. Too many variables.

The standard recommendation used to be .002 for neck tension, then redding changed their recommendation to .001 a few years back. To me, it makes no difference. .001 or .002 is all the same, and I see no difference in accuracy with less neck tension. In fact, over time I probably have done better with a bit more neck tension than with less.

But yes, you probably want to own about 3 bushings per caliber. 1 for step down & neck sizing, and the other 2 for final sizing, taking into account difference thickness of brass