Take the expander ball out of a full length die and size your brass. Now try and seat a bullet. It will be extremely hard due to how much a full length die sizes the neck down. Kind of like an extremely small bushing. Now how is this not more neck tension than using a bushing .002 more than a loaded round? As I said earlier I've had such light tension with a lee collet die you could push the bullets in easily. I guess my pea brain cant understand these higher level concepts.
Neck tension
- Thread starter BrentM
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Mike Matteson
Well-Known Member
I believe you have the cart before the horse. Annealing before sizing, not after sizing. Interesting!
Deputy819
Well-Known Member
Pay particular attention at the 54:20 mark where Jeff Siewert begins to explain the difference between "interference fit" and actual "neck tension".
Orange Dust
Well-Known Member
Backwards from what I do too.
Carey Farmer
Well-Known Member
Yep. Backwards from the way I started out annealing, too. But seems to give a little lower muzzle velocity Es.
Shootin4fun
Well-Known Member
Start annealing asap! It was the #1 thing in improving my ES/SDs. It's reassuring when the resistance of seating a bullet is light and consistent. I started annealing 1:3 firings, but tests showed me that ES begins to increase by then. So now i just anneal after every firing.
Orange Dust
Well-Known Member
IME HBN has a greater effect on ES/SD than neck tension. Not saying neck tension isn't important, just that HBN seems to cover up some of the inconsistencies. I have shot strings where I thought the chrono was broke. Also, cold bore lands in the group with most of my rifles.
Precision loading is a humbling sport. I use .001-.004 depending on what the targets say. It seems that you will not know till you experiment a little. There are few basic "rules of thumb", but trial and error will get you your best results. Only takes a few shots to verify. Some long range shooters use more than .004. Some powders spike pressures more than others, thus the variations in bushing sizes.
Whatever the load ends up liking, it will be night and day from other sizes.
Wilson bushings, when flipped upside down with the number down, will size .0005 more than stamped size on the bushing.
I control the ID with mandrels and annealing to uniform bullet grip.
A general rule of thumb I have found to go buy would be like this:
Medium burning powders like ~.002 tension as a good place to start.
Slow buring powders Like ~ ..003-.004 as a place to start.
You would not think that neck tension of .002 compared to .003 could make much difference, but it is amazing at times.
Whatever the load ends up liking, it will be night and day from other sizes.
Wilson bushings, when flipped upside down with the number down, will size .0005 more than stamped size on the bushing.
I control the ID with mandrels and annealing to uniform bullet grip.
A general rule of thumb I have found to go buy would be like this:
Medium burning powders like ~.002 tension as a good place to start.
Slow buring powders Like ~ ..003-.004 as a place to start.
You would not think that neck tension of .002 compared to .003 could make much difference, but it is amazing at times.
Mikecr
Well-Known Member
When you guys talk about interference of 3-4thou, is that for FL of necks, or partial length sizing? For what cal?
Given the differences to tension I don't see how you can broadly declare anything without these qualifiers.
Then of course there is the alloy & worked hardness, which is mostly unknown, and then we can't even measure neck tension.
Seems like it could be said that we should experiment.
I don't know what phase of load development to include that in. Is it tuning or prerequisite to tuning?
Given the differences to tension I don't see how you can broadly declare anything without these qualifiers.
Then of course there is the alloy & worked hardness, which is mostly unknown, and then we can't even measure neck tension.
Seems like it could be said that we should experiment.
I don't know what phase of load development to include that in. Is it tuning or prerequisite to tuning?
Orange Dust
Well-Known Member
I use mandrels and turned necks. some use bushings. In load development it is after bullet jump for me. Don't know about others.
I don't clean I don't anneal I don't get any cracked necks even after 12 firings. When I develop a load the last thing I check is different neck tensions and there is always a clear winner between 1-5. I am sure this is gonna torque up the ocd in the bunch. And I will bet my ammo is just as accurate as the guy who does every step I have tried in the past that didn't do anything for accuracy. If it doesn't increase accuracy U don't do it. I don't have the time or patience to sit there dilly dallying with brass if there is no return on investment. I would rather be shooting or scouting. JMO
yeah that cleaning and annealing is just for the guys that want that consistent precision stuff.
I have tried not cleaning, not annealing, not using bushings and mandrels, etc. Break in? That was for engines.
Did it for about 25 years that way. It was the best i knew at the time, and wasn't ever shooting beyond about 400yds.
inconsistent was the general rule.
small target hits were an exception, and heck I didn't even use a good chronograph until 15yrs ago or so.
it was a tail chasing marathon mainly. Got my first full custom in 2007, and since then I've strived for consistency. I've added a lot of equipment along the way, but for Me, it's part of the sacrifice to achieve the goal.
Having a close friend that builds customs helps too. We split a lot of large equipment costs and get to play with a lot of cartridges and equipment. Broadens the scope so to speak.
Did it for about 25 years that way. It was the best i knew at the time, and wasn't ever shooting beyond about 400yds.
inconsistent was the general rule.
small target hits were an exception, and heck I didn't even use a good chronograph until 15yrs ago or so.
it was a tail chasing marathon mainly. Got my first full custom in 2007, and since then I've strived for consistency. I've added a lot of equipment along the way, but for Me, it's part of the sacrifice to achieve the goal.
Having a close friend that builds customs helps too. We split a lot of large equipment costs and get to play with a lot of cartridges and equipment. Broadens the scope so to speak.
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