Neck Sizing, how far
- Thread starter Bobr
- Start date
I use Redding Competition Neck Sizing Dies for my 260 Rem with bushings. With 0.002 springback tension, I size the top 1/2 of the neck. Checking case and bullet runout concentricity has shown to be within 0.002" at most. All of that adds up to a load that shoots 140 SMK's in the 0.1" s at 100 m.
Jason
Jason
Bobr said:
"I set my die so that it does not size the full length of the neck. I size approximately 70 percent of the neck, leaving a small part at the neck/shoulder junction unsized to improve the alignment of the case in the chamber. In order to do this I set the neck bushing so that it is not locked down in the die body. When you shake a die, you should be able to hear the bushing rattle (assuming it is not bound up with wax and grease." ... Tony Boyer
Source: THE BOOK OF RIFLE ACCURACY pages 116 & 117.
There's your answer from the "B"enchrest Legend. In stead of saying "I have heard", get a copy of his book and then you "will know" how the benchrest guys do it. It's excellent. Many BR shooters waited a couple decades for it to arrive.
Wish I understood what you guys are talking about. New to reloading and reading only goes so far. It would be great to see this done in person. I have a Lee collet neck sizing die for a 308 win and have loaded a few rounds that actually fired. But measuring neck tension (I couldn't pull bullet out), shoulder set back (my measurement is will it chamber). It's not really as bad as this but it is frustrating to be so uncertain at proper setup of dies, what die will do what, collet vs expander ball, bushing or no bushing, measure from what to what to determine what and why? sooner or later reading this forum is going to turn my light switch on. . Thanks for all the good stuff.
IMHO the lee collet die is great for neck sizing.
Other respondents have been describing bushing type neck sizing dies.
The Redding bushing die is adjustable, by the way of it's construction, for the amount of the neck you want to size.
To achieve partial neck sizing with the lee collet die, one just needs a washer or two.
After the die is properly setup, the shim(washer) is placed over the case, between the shell holder and die. This will allow you to compress the collet, while the shell case is only part ways up into the die. The size of your shims(washers) will determine the amount of the neck that will be sized.
Hope that makes sense, and is at least partially helpful. ;D
Maybe I can take some pics later(if you are interested), they say they are worth a thousand words.
Other respondents have been describing bushing type neck sizing dies.
The Redding bushing die is adjustable, by the way of it's construction, for the amount of the neck you want to size.
To achieve partial neck sizing with the lee collet die, one just needs a washer or two.
After the die is properly setup, the shim(washer) is placed over the case, between the shell holder and die. This will allow you to compress the collet, while the shell case is only part ways up into the die. The size of your shims(washers) will determine the amount of the neck that will be sized.
Hope that makes sense, and is at least partially helpful. ;D
Maybe I can take some pics later(if you are interested), they say they are worth a thousand words.
Bushing dies left (pic )essentially allows you to change the neck tension of the brass you are resizing, by simply changing out the bushing inside the die.
The Redding competition die allows complete resizing of the neck. The non-Bushing die (right) is what ever the factory hones it to.
The competition bushing set has 3 dies one bullet seater one neck size and one body die… Essentially a full length size die…. with out touching the neck. Just the shoulder and body of the case.
The Redding competition die allows complete resizing of the neck. The non-Bushing die (right) is what ever the factory hones it to.
The competition bushing set has 3 dies one bullet seater one neck size and one body die… Essentially a full length size die…. with out touching the neck. Just the shoulder and body of the case.
Attachments
Shynloco
You can lead a horse to water, but ........
Outdoorsman said:
Excellent advice! I might also suggest folks truly interested in ACCURACY read "Extreme Rifle Accuracy" by Mike Ratigan as well. I believe readers need to take from these books what you will, but then you must apply whatever method excites you to YOUR PARTICULAR RIFLE to find out what works best in her. I've found some methods work in one rifle (6mmbr), while other work better in a different ones (.308 - 6.5mm).
Anyone use the Lee collet neck sizing die? I'm not sue how much of the neck is being sized. As far as I know there is no adjustment for this. what is the best way to take the measurement of the tension?
bushwacker_hock said:
To understand how most folks describe neck tension, you need to measure outside diameter of the case neck after sizing, then measure the loaded round. The difference in the neck outside diameters is what folks are describing as neck tension.
There is no way of adjusting the lee collet die for neck tension without modifying the center mandrel. The way it come from the factory usually gives about .0015 - .002" tension on the bullet.
You can increase tension by taking the center mandrel out, chucking it into a drill and polishing down the center mandrel a bit. This will allow the neck to get squeezed smaller by the collets. Lee will also sell the center in other sizes that might be desired, or you can get an oversize mandrel and turn it to the dimension that you desire.
In my experience the way it comes from Lee is totally sufficient. I let the brass 'rest' a few days after I use the Lee collet neck sizer, so that the neck tension eases up a bit before loading. The brass tends to spring back slightly from the compression, and the seating force seems to feel more consistent by letting the case rest a few days.
BoydAllen
Gold $$ Contributor
Accuracy is one of those "weakest link" things, and it is easy to become distracted by some detail that does not matter very much. The issue of how much of the neck to size would be an example. Tell us about your rifle, rest setup, whether you are shooting over some sort of sticks with ribbons, or flags, how you work up loads, and what level of accuracy you can consistently achieve. By looking at the entire package, we may be able to identify areas where you can make some gains.
Atta boy Boyd....
I've played around with this years ago and found one thing to be true, consistency. 25%, 50%, 75%, its all up to you but the important thing is what ever you decide on, do the same every time. Bench shooting is all about repeating the same conditions shot after shot. An old-timer once told me "you can shoot a match while standing on your head and a finger in your bum if you want, just make sure you do it the same way every time." I found this to be true. Try a way you like, then stick with it.
Outdoorsman said:
I will agree that when using a bushing die neck tension seems to increase with time, However, I have found that with the Lee collet neck sizer the opposite occurs.
If you seat immediately after sizing there is noticeably more force required, while if the brass rests 3 or more days less force is needed.
I have no type of gauge or measuring equipment to test this and I have no numerical data, but this has been my experience with using the Lee collet in .308 and .30-06. ;D
Actually, it happens opposite the last action, with ALL sizing.
Necks, body, shoulders, primer seating, bullet seating.
With collet sizing the last action is inward. The brass relieves itself of some of this stress outward, most initially(springback), then continually less with time.
Same with shoulders, body & primer pockets.
With bushings, expansion should follow, setting up for initial and then this chronic springback inward.
With bullet seating the last action is outward & actual neck up sizing if you set neck IDs more than ~1.5thou under cal. This, I feel is a bad idea because the inward springback(your tension) continues over time if you set up that much stress. But with collet die use this could work to counter the observed 'problem'.
None of this matters for quick range ammo. Just what you're keeping in the safe for use down the road.
Necks, body, shoulders, primer seating, bullet seating.
With collet sizing the last action is inward. The brass relieves itself of some of this stress outward, most initially(springback), then continually less with time.
Same with shoulders, body & primer pockets.
With bushings, expansion should follow, setting up for initial and then this chronic springback inward.
With bullet seating the last action is outward & actual neck up sizing if you set neck IDs more than ~1.5thou under cal. This, I feel is a bad idea because the inward springback(your tension) continues over time if you set up that much stress. But with collet die use this could work to counter the observed 'problem'.
None of this matters for quick range ammo. Just what you're keeping in the safe for use down the road.
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