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preventing runout
Posted: Wed Dec 12, 2007 12:40 pm
by brokeasajoke
From some reading of old posts it seems a forster CoAx press will minimize runout. Lets assume we dont have a CoAx and the norm "C" type presses. I,ve always been told to press the bullet halfway pull it back down twist the shell a half turn then fully seat the bullet. Is this standard practice? Are there any other tips and tricks to prevent runout? thanx
Re: preventing runout
Posted: Fri Dec 14, 2007 4:28 am
by skipper
brokeasajoke
For me, controlling runout starts with the case. If there's runout between the case shoulder and neck, it will still be present when you start seating and can give the appearance that the seating die is defective. You have to start with concentric cases. Here are the steps I use to control runout:
1) I start by neck turning just enough to take the high spots off. If the necks aren't a consistent thickness they can induce runout noticable after seating.
2) After I fire form my brass, I check for runout at the neck of my empty cases. I check because I want to know if my chamber is inducing runout.
3) After neck sizing I check again to make sure the die isn't inducing runout. If it is, I would just get rid of it. There's no sense in trying to work with equipment that's out of round.
4) After seating I check again to see if the seating die is inducing runout.
If you're really serious about controlling runout, you need to check each step where you could possibly induce runout. If there is no runout just before you neck size and then there is afterward, then you have found the culprit. Once you find where the runout is coming from, it's easier to solve the problem. If you just check for runout after seating you're not going to solve the problem by turning the case and pressing again. If you start the seating process with concentric cases you'll have much better results.
Re: preventing runout
Posted: Fri Dec 14, 2007 7:17 am
by brokeasajoke
Is there an acceptable amount of runout? Does the CoAx really help or is that a marketing gimmick?
Re: preventing runout
Posted: Fri Dec 14, 2007 7:55 am
by skipper
Acceptable runout depends on the application. Generally speaking, for hunting runout should be kept to about .004, for target shooting and long distance work about .002, for competition shooting .001 or less if possible.
I have noticed that keeping runout to a minimum helped me reduce the amount fliers and reduced the distance the fliers were from the main group.
The Forster Coaxil press is definately a step up from a conventional press like an RCBS Rockchucker due to design. A "C" type press can suffer from flex. An "O" type press suffers less flex. If you want the ultimate press for seating, try an arbor press with Wilson dies. That's about as good as it gets. You can even have the dies cut to match your rifle chamber. If you add the strain gauge to the press you can actually measure seating force and use that information to help get neck tension more consistent. Just be aware that an arbor press is just used for seating. They weren't designed for sizing operations.
Re: preventing runout
Posted: Fri Dec 14, 2007 4:50 pm
by Silverfox
skipper-- When you stated:
Just be aware that an arbor press is just used for seating. They weren't designed for sizing operations.
Are you including
JUST full-length resizing in there or neck sizing too?
I would think that an arbor press is fully capable of handling the neck sizing operation, but that's JMHO.
Re: preventing runout
Posted: Fri Dec 14, 2007 8:56 pm
by skipper
I can't speak for other arbor presses that I haven't used but the K&M press isn't threaded to accept a die to begin with and it doesn't have provisions for a shell holder to pull the case out of a die. I don't think there is any way to use it to size, period. I'm still new to the arbor press thing, though.
I use a Wilson bushing neck sizing die. All you need is a plastic faced hammer. You slide a case in the die, then turn it over on a flat surface, cover the die with the base and hammer. That forces the case fully into the die performing the neck sizing operation. Then you remove the base, flip the die over and hit the decapping pin on the reloading bench to pop the primer, if present, and eject the case. There's no need for a press. You can actually do this whole process without the hammer by just slamming the die down on a flat surface, like the bench for both operations.
Re: preventing runout
Posted: Fri Dec 14, 2007 10:47 pm
by Phasor
I use a Sinclair arbor press with Wilson bushing dies and seating dies. There is an included base to use with the sizing die that elevates the die and traps the spent primers under the base. It doesn't take much force to neck size the brass. And Skipper is quite correct in that runout is held to minimum with these hand dies. I use it for several different calibers and it works fine until you have to full lenth size and then I use my Rockchucker for that with a screw in die.
Phasor
Re: preventing runout
Posted: Sat Dec 15, 2007 1:36 pm
by Silverfox
Here's a link to a discussion on arbor presses that took place on this board back in August of this year.
http://rugerhunting.com/forum/viewtopic.php?f=4&t=3800
skipper-- you posted the exact same photo of your arbor press setup in that thread as you did in this one. I posted photos of my Haydon arbor press and had photos of my Wilson bushing neck sizing dies right in that same thread!!! The arbor press I have works just GREAT for neck sizing and, like was mentioned by another poster above, with the accessory base you don't need a shell holder like a normal press where you have to thread the die into the press.
I'm not sure I would take on full-length resizing with my arbor press though
Re: preventing runout
Posted: Sat Dec 15, 2007 3:21 pm
by skipper
Silverfox
I remember that thread. Looking at your press again I can see where yours is well suited for neck sizing. I'm not so sure about the K&M though. It has a stack of Bellville washers that are flexible. I dohn't have any information as to how long these washers will hold up to repeated use. I would hate to wear them out sizing when I don't really need to. The hammer method is really pretty quick anyhow.
Another thing I noticed is that it seems you only have one set screw to loosten to adjust the height of your press. Mine requires loostening four screws on the back of the support arm. I would hate to have to reset the height every time I switched from sizing to seating since the dies are different sizes.
Re: preventing runout
Posted: Sat Dec 15, 2007 6:40 pm
by Silverfox
skipper--You are correct in assuming there is only one big Allen screw that has to be loosened to make vertical adjustments on my arbor press. I can see that yours would take a considerable amount of tinkering to adjust vertically. You could buy two arbor presses and use one for seating and one for sizing.
Sorry, I couldn't resist throwing that two-arbor press idea
How much did the K&M press cost, if you don't mind my asking?
Also, I'd hate to see you ruin your arbor press by taking on neck sizing and putting too much stress on the press. Have you checked with the owner of K&M to get his take on whether he feels his brand of arbor press could handle neck sizing with Wilson type bushing neck sizing dies?
When I use my Haydon arbor press it sure doesn't feel like it take much force to neck size my casings, but then I imagine there is a pretty good leverage advantage going here too so it is probably hard to really tell how much pressure it is taking. I only neck size my .17 Remington and .204 Ruger casings in this arbor press.
Re: preventing runout
Posted: Sun Dec 16, 2007 4:42 am
by skipper
I can't find the receipt, but I think it was right around $125 without the gauge. I got him to throw in the Mitutoyo gauge for another $50. I think I've seen that same gauge reatil for $90.
I haven't asked about neck sizing using the press. I'll probably give them a call tomorrow and see what they say.
Is my memory correct that I thought you had sprung for a Ken Light Annealing machine??? If so, how is it working out?
Re: preventing runout
Posted: Sun Dec 16, 2007 9:57 am
by Guy M
My arbor press is by RWH, nice piece of gear. I use it with Wilson dies for the .204, .25-06 and .308 Winchester. Use it for both neck sizing and seating. Those Wilson dies are great for minimizing runout!
Re: preventing runout
Posted: Sun Dec 16, 2007 2:35 pm
by Silverfox
skipper--Sorry to report this, but I haven't even set up the Ken Light annealing machine yet and I have had it for over 1½ years
My supply of brass for my .204 Ruger and my Pac-Nor barreled .17 Remington is such that I still haven't fire formed all the .17 Remington casings I neck turned. I think I had something like 650 of those casings and still have at least 100 of them yet to fire form. I have fired some of them three times and might try some annealing after the fourth firing.
Same story for my .204 Ruger brass. I have about 700 casings that I have fire formed and some of those 700 have been fired up to three times. I don't think I'll anneal any of those until the next firing or so.
It's a different story with the brass for my Lilja barreled .17 Remington that my son shoots. Most of the brass for that rifle has been fired at least 6 times minimum and many casings on on their 8th or 9th firing. All of these casings have been neck sized with my Lee collet die each time, except after about the 5th firing, I used my full length die to set the shoulder back a wee bit. I think these casings are going to be the ones I do my "test annealing" on. However, I will take some throw-away casings to do the initial testing to get the torches set up and find the correct temperature.
I think I'll probably wait until summer comes and set up the annealing machine in my garage. Before that time, I might set up the annealing machine in my basement just to see how it operates.
Re: preventing runout
Posted: Sun Dec 16, 2007 4:58 pm
by skipper
I hope you take some videos. I'd like to see it in action.
Re: preventing runout
Posted: Mon Dec 17, 2007 2:41 am
by Lee C.
Skipper I have the K&M press and you don't have to change the height on it. Going from neck sizeing to seating your bullets. And it takes vary little force to neck size a case at all.