cherry reloader....

[AaronSDMF82]

First post, ive been lurking this site for about a year, very helpful.

My question, Im reloading (just started) a 6BR, with lapua brass loaded with a 105 berger I have a 269 neck, so I use a 268 bushing in my redding comp seater die, however with a loaded case i can pull out the bullet with my hands with not to much trouble.

Now, you might ask why were you trying to pull bullets out of a loaded cartridge in the first place, when I was seating my bullets, SOME of the bullets would seat super low, almost sinking into the case. These are once fired cases sized 268 3/4s down the neck, just started happening. What im thinking is to use a smaller bushing like a 267 or 266 but that goes agaisnt want Redding says...

I know this sounds this is newbie question, and I tryed searching didnt find my answers, thanks.

 

[RonAKA]

I agree with what Rich says about neck tension. If your neck OD in a loaded round is 0.269, then you need a bushing which is 0.002" smaller, to get a 0.001" fit (or tension). The reason is that the brass springs back about 0.001". So when you put it in a 0.267 bushing, then it springs back to 0.268" when you take it out. Then when you load it, the OD grows to 0.269", confirming you have 0.001" fit.

Surprised that Redding does not explain it more clearly. Forster's instructions are very good. See bottom right of page 1 at link below. Also note this is for target loads. If used in a magazine then you need 0.001" tighter still, or if you use moly bullets you may also need to go 0.001" tighter.

http://www.forsterproducts.com/client_images/catalog19938/pages/files/Bushing_Bump_Neck_Sizing_Die_DIE-0008.pdf

My loads measure 0.269" loaded and I use a 0.267" bushing. Works fine.

 

[AaronSDMF82]

Ok good deal, thanks rich and ron.

 

[fdshuster]

And do not count on the neck bushing you are using to give you the exact sizing diameter as the stamping ident on the bushing. A lot of my bushings, both Redding & Wilson will size down the neck diameters to .001" to .002" smaller than "advertised". Some are so far off I have to keep a correction chart with each set of bushings, and caliber does not matter, 22, 6mm or 30.

 

[bozo699]

Frank,
Why do you think that is? I mean you pay premium price for redding ,forester,and wilson and the bushings are never perfectly cirmetrical or the exact size listed. Anymore I use the bushing dies to play with seating depth once found I buy a regular redding die and have a machinist grinde it to specs, or I have him turn me out a carbide bushing on his brown & sharp. They are allways perfectly cirmetrical and exactly the correct size.
Wayne.

 

[RonAKA]

I don't have an inside mic to properly measure my bushings to a tenth of a thou, but to as close as I can measure with my vernier my two Forster bushings are the same size as they are stamped.

One possible explanation for variance may be the manufacturing process, and when they are hardened. If they harden after final machining then the dimension can change. You would think in a premium product they would hone with a grinding compound to get the exact size and a good finish. But, that can be time consuming.

I noticed that my Forster bushings say they are Cryo treated, which I assume means cooled to a very low temperature. Not familiar with the method and what effect it has on dimensions.

 

[fdshuster]

Ron: I'm not attempting to measure the I.D. of the bushings, since I also do not have a proper tool to measure an inside diameter. I base my measurements on what the case neck O.D. is after proper sizing, and the majority of times the case diameters are smaller than they should be, some as little as .001" but a very few as much as .0025". Can't be springback because I would think that would be a larger size. Using Imperial Die Sizing Wax, the least amount possible, so it can't be too much lube. This is the main reason I will not buy the very expensive titanium or carbide, whatever they are made of. It's bad enough to have a collection of bushings gathering dust that cost $11 each and even at that my "collection" is well over $100.

 

[bozo699]

Frank,
I don't have the proper measuring tools to measure that close of tolerances either.
One time I was having some trouble getting a gun to group, My machinist/gunsmith
friend of mine started checking things, one thing he noticed that my sized brass necks wern't concentric and were tapered,not a gross amount but it was there. So he measured my bushings and mandrels, neither of which were perfectly true. I ask why @ the hijacked prices were they not perfect? his answer was to get quantity they are mass made by whatever machines they use. He grindes the tooling he makes for me, he said it is much more precise than turning and according to his way's of measuring it is. ( The main problem ended up being a bench problem) But in the process of elimitations we found these inconsistancies with my redding and sinclair tooling. I now buy over sized mandrels and he grindes them down to exact size I want on a Brown&Sharp precision grinder and makes my bushings from scratch.They are now near to perfect, I don't know if they make me shoot any better but it makes me feel better knowing they are closer in tolerance.I also have him hone out regular $30 redding n/k and f/l sizing dies once I find the neck tension I want with the bushing dies. Anyway that is part of my process for whatever it is worth.I am constantly learning new techniques and trying different things on the way, the same as the rest of you I guess. Most of the more precise methods of reloading and shooting techniques I have learned came from you all right here on 6br and continue to learn daily, please continue teaching Thanks
Wayne.