Choosing the right bushing?

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Shrinkmd

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I was using my new micrometer to measure the case necks on my 223 factory ammo which I plan on reloading. I have some Winchester which runs .249 on average, and some PPU which was less consistent and seemed a bit larger, more around .249-250. I was trying to measure the middle of the neck, and only enough tension to pick up the cartridge, but not mashing the micrometer until it doesn't turn anymore. Does this sound like the correct technique? Should I be turning each cartridge and averaging multiple measurents?

According to the Redding directions, I should choose a bushing 0.001 smaller than the smallest case. That would yield a 247 or 248.

Does this sound correct? I am likely using mostly fmjbt bullets, which I have read can act as their own expander if the fit is close enough.

For now these will be shot through a standard 20" bushmaster target model, but at some point I want to get a nice bolt gun. So I'm trying to learn techniques and use the tools which may bring more accuracy and better brass life later.
 
I would try a .247 to start, but you will surely end up with more than one bushing. It will be a waste of time with FMJ bullets. Get any cup and core bullet with a solid base (soft point, hollow point etc.) and the results will be much much better.

The best way to practice with a micrometer is to get a standard and practice on it. It's a feel thing, not too light, not too heavy, with consistency being the biggest part.
 
Walkalong is correct, you are wasting your time with FMJBT bullets and you will indeed end up having more than one bushing, as you will no doubt be using more than one make of brass which will require more or less neck tension. Also, one thing about bushings that not everyone knows, the amount of neck reduction can be influenced by the amount of neck reduction that is necessary. What I am saying is, let us assume that you want to resize your necks to .247" and your fired brass comes out of your rifle measuring .253". So, you buy a .247" bushing, resize your necks, and you will likely find them measuring .246". What happens is when you have to reduce your necks by .005" or more, then the brass is sized smaller than the bushing die. This is why many of us run our brass through an intermediate size bushing first (say .250") before using the .247" bushing to get true .247" necks. Conversely, you can take the additional .001" of sizing into consideration and order a bushing .001" larger than the size you want to end up with. Hope that helps.

Don
 
Neck Tension

I have the same problem with my 260 rem reloads the lapua brass has thicker necks than remington. You will probably find the overall case capacity is different as well. Buy 2 bushings or 3 expieriment with neck tension once you find a load that works. Some firearms like more.
 
I'll go one step farther, and say that you are wasting your time using a bushing die with a Bushmaster. In my opinion, bushing dies should be used on brass that has been neck turned. Semi-autos also perform better with full length resized brass. I would use a full length sizing die and not look back. When you get a bolt gun, I still would not worry with a bushing die unless I was turning necks. Even Lapua has enough inconsistency to cause your neck tension to be all over the place. Now, if you have a custom barrel with a match grade chamber, a bushing die is great. Lightman
 
This is all good advice. test it if you want to, but out of an AR, you probably won't notice much for all of your efforts. But let's face we all do some things that aren't much help, superstition maybe?
 
From the OP:
For now these will be shot through a standard 20" bushmaster target model, but at some point I want to get a nice bolt gun. So I'm trying to learn techniques and use the tools which may bring more accuracy and better brass life later.
But yes, for the AR light neck tension could be problematic. If I was going to use a bushing die for an AR, it would be a full length die, and I would not go so light on the neck tension.

I do not agree that bushing dies should only be used with turned necks, but yes, that is best. The next best is good brass with consistent neck thickness.

There are several ways to load very accurate ammo. Most times the limiting factor is the gun and the shooter.
 
I guess I'm a sucker for Redding products sometimes. It feels like the quality might rub off on your targets.

I bought the full length resizing bushing die, as well as the carbide ball. I guess I'm trying to maximize whatever accuracy I can squeeze out of what I have, but avoiding processes like neck turning or annealing which are inappropriate for an AR chamber.

I can also try making up the same loads in brass from the same batch and just vary the extra stuff, such as x-die vs redding bushing s die. I also want to try crimped vs not crimped. I've seen lots of info on how to make the most obsessively perfect match ammo for super target guns. It seems more unclear what advanced techniques offer anything of value for lesser components.

Of course, it's always fun having new reloading tools and trying out something new
 
I'll go one step farther, and say that you are wasting your time using a bushing die with a Bushmaster. In my opinion, bushing dies should be used on brass that has been neck turned. Semi-autos also perform better with full length resized brass. I would use a full length sizing die and not look back. When you get a bolt gun, I still would not worry with a bushing die unless I was turning necks. Even Lapua has enough inconsistency to cause your neck tension to be all over the place. Now, if you have a custom barrel with a match grade chamber, a bushing die is great. Lightman

Lightman,

This a myth on the internet perpetuated by people who have never used bushing dies. First, you seem to be under the impression that when you use bushing dies you are not full length resizing your brass. You can either just neck size the brass or full length resize it when using bushing dies. Secondly, there is simply no reason not to use bushing dies with brass that has not been neck turned. I used bushing dies with un-turned brass for 6 years in 1,000 yard F Class competition, and most of the guys on the firing line with me did so as well. And finally, you should never use the word "inconsistency" and Lapua in the same sentence; it's that good.:D

Don
 
Well Don,
You made a lot of good points. I guess we both have our opinions. I have also shot F Class and long range benchrest in competition. I also own and use a few sets of bushing dies, so my opinion is not just internet hype. There is at least a little experience there.
You made at least a couple of points that I failed on, and that was about full length bushing dies. I have never used them, and tend to forget about them. I tend to think neck die, when I hear about bushing dies. My bad! I still feel that you are not getting the most benefit from them without neck turning, but to each his own. I also agree that while not perfect, Lapua is about as good as it gets. I know, I said it again! I'm sorry!:)
Shrinkmd,
I hope I did not come across too harsh, and if so, I'm sorry. I hear you about having new tools! Back to your question, with a semi-auto, or unturned case necks, I would look at more that .001. Probably .002 or .003. Most bushing die users start with about 3 different size bushing. And I agree, Redding is very good! Lightman
 
I am using a Redding FL bushing die for my F Class ammo, and it shoots extremely well. Will it out shoot my 6PPC Bench gun with a .262 neck, with case necks turned to the nearest .0001, using a custom FL bushing die? Nope, but there is more to it than the sizing.
 
No worries. That's what I enjoy about THR, that we can discuss interesting and sometimes controversial topics in a positive manner. It's always fun trying to game the equipment + money + skill + obsessiveness = accuracy equation. Maybe someday I'll get some souped up target rifle compete. For now, I'd be happy shooting well at the 200 and 300 yd line with my AR and the military surplus bolt guns.
 
Walkalong, I clicked on the link that you posted. Is that something like a lock-in-load bushing with your die set? Lightman
 
Yes, I am loading it on my LNL, and getting .0025 to .001 run out. That is with light neck tension, or as some like to say, bullet pull. Heavy neck tension ruined the concentricity.

Using a Wilson hand die and Arbor press for seating gave the same results. Notice the multiple bushings Shrinkmd. You never end up with only one.
 
Bushings For Auto Loading Rifle

a standard 20" bushmaster
Find the loaded round neck with the smallest diameter. Pick a bushing .002" under that diameter, as the brass will spring out after sizing. Even better .003" as chambering a round in an auto can move the bullets. http://www.exteriorballistics.com/reloadbasics/gasgunreload.cfm The 223 neck gets over worked because of large chambers & thin brass neck walls. Sizing down more than .008" of the fired brass in one step, may not work well with bushings. Plus you should use the expander, if not neck turning. An expander at .222" will tell you if you have enough neck tension/bullet pull. You want a very light drag as its pulled thru the necks.
 
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The exterior ballistics article is great, thank you for the pointer. It really answers a lot of questions for the semi auto rifle loader looking for accuracy in a safe and relatively sane manner.

Luckily, I have a decent amount of single headstamp brass, so I guess I will try and find the right bushing size to create enough neck tension that I don't need to crimp the finished product? That seems to be the goal, not working the neck more than necessary but also avoiding crimping?
 
Correct, with the right neck tension, no crimp is needed. The neck should be expanded about .002" on seating the bullet into a sized neck. This gives about 35 to 45 lbs bullet pull. Using a Redding die, the bushing should float inside the die. It may or may not size the complete neck fully to the shoulder.
 
I did some more careful measuring of my PPU07 5.56 brass. Unfired cartridges measured from .24745 up to .25050, but most were around .24950. Then I dug out the fired brass, same lot, all fired in my rifle. Those were .25450 to .25530

So, it looks like there is a difference of .006", so I guess I need a bushing .001" larger than normal since I am only planning on sizing once for my service type rifle. So I want my necks to be about .246 or .247 to give me a finished size of the .248-.249 I measured in fresh ammo.

If I only want to buy 2 bushings (yeah right I know they multiply) would the 247 and 248 be the best place to start? Or should I just get 246, 247, and 248?

Also, I'm assuming that I'm trying to avoid the expander ball. I had ordered the Redding carbide ball in .224, but I guess that would lower the neck tension I'm trying to create, no? Would that be better for a run of mixed range brass for more plinking rounds? The PPU07 brass may not be super consistent, but at least it's all the same headstamp and lot.

So much to learn.
 
I use a carbide expander ball in a FL sizer for mixed brass for plinking rounds. I have a load worked up for brass up to "XYZ" weight. I scrap the few extra heavy ones.

I think I would still start with the .247 and see how neck tension is on the thinner walled brass. Go from there. The math doesn't always work out just right when sizing that much.
 
Redding Bushings

The stamp(.247") on the bushing should be facing down, towards the case mouth. About every third case, a tiny amount of lube on the case neck is a good idea, with the titanium bushing. A boatail bullet may not need an expander.
 
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