How many reloads for your AR brass?

Originally Posted By: SfsmedicOriginally Posted By: CatShooterOriginally Posted By: SfsmedicOriginally Posted By: CatShooterOriginally Posted By: K_V_VHow much setback in headspace are you guys going for on your gas guns? I was planning on bumping the shoulder .001" but I also want them to cycle reliably. Not new to reloading, just new to reloading AR's. 223 Wylde chamber and standard rcbs dies btw.

Headspace will not affect feeding - but it can affect the final lock-up.

There is nothing about 0.004" that has any meaning.

Neck size until you have lock-up problems, and then move the headspace back 0.001" at a time until there is no lock-up drag. Then lock the die setting.



Let me clarify then. Get a hornady or Sinclair headspace gage so you can measure the fire formed brass. Use the fire formed brass as your chamber size and bump the shoulder back .004 from that chamber size.

If you don't bump it back enough it may fully close on your round but you will have one heck of a time manually opening the chamber. See the thread on mortaring your AR.

Let me clarify then.

A fired case does not give you the headspace - it may need several firings until it is "chamber length".

Only then, can you use it as a starting point - and if you size 0.004" shorter for each firing, you will have very short case life, cuz the cases will stretch 0.004" on each firing.

Five firings at 0.004" equal 0.020" stretch - very badd!

And Higgie, Dude... you know - I mean you KNOW - that you need to be using small base dies. Don'cha??



I disagree and an easy way to find out. Fire a few cases. Load them in the gun and then manually extract them. See if lock up isn't extremely tight.

I never said I bump back .004 each time. I said I bump .004 from chamber size. In my manual it says my chamber size for each gun and the desired shoulder measurement for that gun. That is how I achieve the measurement. If 8 loads on my 6.8 isn't a lot then I guess I'm happy. Because that's where I am and so far the brass is still fine.

My rifle has a 1.350 chamber size and I bump back to 1.346 which is where my Dillon tool head is now set up for that gun. I check it but never need to adjust. I am not measuring and readjusting every time. Because my chamber size doesn't change. I can check the brass on its 1st fire or 5th and it will be right at 1.350 after being fired from that gun.

Also five firings from 1.350 resized to 1.346 each time equals .004 each time it's not accumulated math. These are both bolt guns that get neck sized multiple times until the bolt is hard to operate than needs a .002 shoulder bump to start over. You have to bump them back or they will not get proper lock up and then the firing pin might just go tap instead of bang and you will be wrestling it trying to get it to come unlocked to load a different round.

The most common issue we see with ARs is people not bumping the shoulder back far enough on their resized brass and then wondering why they can't manually extract the unfired round.

This is addressed in Dave Brennan's book Precision Shooting: Reloading Guide and my technique I'm discussing is from his pages addressing shooting the AR

This is the tool I use to measure fired brass and determine chamber size. I measure several cases to determine initial length to test with on a new rifle. http://www.hornady.com/store/Headspace-Gauge-Kits/

So all chambers are cut to the exact same dimensions??
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i should read more books.
 
That was never stated. The technique I'm discussing was stated in the book.

I stated find your chamber size whatever way you choose. I use the hornady headspace gage linked above to measure a few pieces of fired brass that are now fire formed to my chamber. That allows me to find my chamber size and right it down in my reloading book for that rifle. When reloading that rifle I go off that measurement as the chamber size and bump .004 smaller than my rifles chamber.

I have a book for each rifle because they all are slightly different.
 
The hornady tool is fine IMO. They key is being able to take a repeatable measurement off the shoulder of the cartridge. If I take a fired piece is brass and measure the shoulder headspace at X" then size that brass and measure again at the same point on the shoulder I can see that I have moved the shoulder back by .00X". I don't see how a bevel on the gauge opening would affect your measurement when measuring a case at the same place every time. I understand your point that the actual measurement from the base of the tool is effected by the bevel instead of reading from the opening of the hole. But again the actual number reading is irrelevant so long as you are using it to determine the amount of set back you have achieved. If I am wrong about this I am sure I am about to get told what's up. But I have never had a problem correctly adjusting headspace with the hornady tool.
For what it's worth I plan to use standard dies and am sure they will be fine. I guess I can revisit the issue if it causes a problem in my gun. As stated I am shooting a barrel with a Wylde chamber. My plan for this gun is to keep it simple. FL size every time for reliable feeding and function.
 
Kyle, unless I'm mistaken the chamber in your gun has a different THROAT to allow for more leade. I might be wrong there. It shouldn't change the shoulder measurement.
 
Ok I think I know the answer to this question/statement but that's no reason not to pose it.
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Let's say you have 100 pieces of AR 223/5.56 (whatever caliber) "MISC" brass and its all been fired 3-4-5 times thru your AR. You have set your die to size (pick any number).004 shoulder bump.How many pieces are going to measure out .004?
I use a RCBS Precision Micrometer for .223 and it measures very exact from what I can ascertain and I would say that 80% would be .004 but a good number of cases would be not set back at all and some would be too "long" to chamber.
I have also found that using Small Base dies makes this issue even worse.
 
Originally Posted By: venaticOk I think I know the answer to this question/statement but that's no reason not to pose it.
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Let's say you have 100 pieces of AR 223/5.56 (whatever caliber) "MISC" brass and its all been fired 3-4-5 times thru your AR. You have set your die to size (pick any number).004 shoulder bump.How many pieces are going to measure out .004?
I use a RCBS Precision Micrometer for .223 and it measures very exact from what I can ascertain and I would say that 80% would be .004 but a good number of cases would be not set back at all and some would be too "long" to chamber.
I have also found that using Small Base dies makes this issue even worse.


I have both tools. Kyle up above has it figured out for his use. I do the same process. No matter what the book says any measurement on that shoulder will give us what we need. The Hornady insert of 350 works perfectly fine on a 360 diameter data line shoulder.

The RCBS is one fast tool for checking things. I use mine for rapid sorting on loaded ammunition as a double check if I am concerned about 100% reliability like in a 3Gun match. Using a hodge podge of brass I too note the variation of shoulder movement. I haven't seen any that stayed at zero movement that were too long but I am sure it could happen.

Greg
 
Originally Posted By: HidalgoKyle, unless I'm mistaken the chamber in your gun has a different THROAT to allow for more leade. I might be wrong there. It shouldn't change the shoulder measurement.

Right you are. I was providing that info for a basis of comparison. Still curious how much shoulder bump I need when I FL size my brass... I will prob just size it and shoot it and see how I do. If I require more bump I will tackle it at that point. I don't however feel the need to be using small base dies.

As for variations in shoulder bump in a given lot of brass like Venatic spoke of, my theory is it is dependent upon how many reloads you have on each piece of brass, i.e. how much has that piece been work hardened through reloading/ shooting cycles. The more work hardened the brass the less likely it will want to be moved by your die. Therein lies the need for annealing to achieve consistency in sizing and neck tension. But hey, these are gas guns not bolt rifles and were talking minute of coyote not bench rest.

Greg, the Wilson case gauges are also another fast effective way to check headspace and sort brass. Pop the brass in and visually see if something is way out, but you can measure off of it too with calipers to the base of the brass.
 
For general stuff I run 0.004. For loading them singly I am down to 0.002. If I am dead set it has to run no matter what I'd set up for 0.005 - 0.006. On that ammunition I won't be shooting it over and over again.

Greg
 
Originally Posted By: GLShooterFor general stuff I run 0.004. For loading them singly I am down to 0.002. If I am dead set it has to run no matter what I'd set up for 0.005 - 0.006. On that ammunition I won't be shooting it over and over again.

Greg

Greg thank you for chiming in and with the same or similar numbers what I was stating earlier.
 
Originally Posted By: K_V_VOriginally Posted By: HidalgoKyle, unless I'm mistaken the chamber in your gun has a different THROAT to allow for more leade. I might be wrong there. It shouldn't change the shoulder measurement.

Right you are. I was providing that info for a basis of comparison. Still curious how much shoulder bump I need when I FL size my brass... I will prob just size it and shoot it and see how I do. If I require more bump I will tackle it at that point. I don't however feel the need to be using small base dies.

As for variations in shoulder bump in a given lot of brass like Venatic spoke of, my theory is it is dependent upon how many reloads you have on each piece of brass, i.e. how much has that piece been work hardened through reloading/ shooting cycles. The more work hardened the brass the less likely it will want to be moved by your die. Therein lies the need for annealing to achieve consistency in sizing and neck tension. But hey, these are gas guns not bolt rifles and were talking minute of coyote not bench rest.

Greg, the Wilson case gauges are also another fast effective way to check headspace and sort brass. Pop the brass in and visually see if something is way out, but you can measure off of it too with calipers to the base of the brass.

That's exactly where I was going. If you have all your brass the same as in same brand, same age, same reload time etc then you MAY be able to get a constant but I have thousands and thousands of pieces and I am loading for volume shooting (3 Gun)so I size as much as the die and press will do(that varies)
and I get a few pieces per hundred that running thru 3 times still they are too long for an AR as they are work hardened. these are the ones I thought a Small base die might help...nope made it worse. It just forces more brass up.
Just my experience.
Anybody need almost new Small base Dies?
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Originally Posted By: venaticOriginally Posted By: K_V_V
Hidalgo said:
Kyle, unless I'm mistaken the chamber in your gun has a different THROAT to allow for more leade. I might be wrong there. It shouldn't change the shoulder measurement.

That's exactly where I was going. If you have all your brass the same as in same brand, same age, same reload time etc then you MAY be able to get a constant but I have thousands and thousands of pieces and I am loading for volume shooting (3 Gun)so I size as much as the die and press will do(that varies)
and I get a few pieces per hundred that running thru 3 times still they are too long for an AR as they are work hardened. these are the ones I thought a Small base die might help...nope made it worse. It just forces more brass up.
Just my experience.
Anybody need almost new Small base Dies?
lol.gif


I've never run thousands of pieces of brass in 3GUN. Maybe 500 in rotation or so. I shoot a 6X45 and pretty much reuse it if I can get it. I usualy won't run range pick up in the mix in that chambering as I like to know the history. Of course I have acess to once fired stuff pretty easily so I am blessed there.

Those work hardened ones are a pain. I've hit a few of those over the years. OL They go in the scrap as I don't want to anneal onsey twoseys.

Greg
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I can see annealing something like 260AI brass that you put some time and money into. That makes pefect sense. But taking the time to anneal 223 seems like a giant waste of time. Just buy another 1000 lake city and keep on rolling. Venatic I think your right about the SB dies. They will work the brass even more. They are designed for match chambers (read tight). I would think a body die would do the trick for those hard to bump shoulders so long as it were shorter than standard length dies. Then again just pitch them like you said and don't waste the time.
 
Originally Posted By: K_V_VI can see annealing something like 260AI brass that you put some time and money into. That makes pefect sense. But taking the time to anneal 223 seems like a giant waste of time. Just buy another 1000 lake city and keep on rolling. Venatic I think your right about the SB dies. They will work the brass even more. They are designed for match chambers (read tight). I would think a body die would do the trick for those hard to bump shoulders so long as it were shorter than standard length dies. Then again just pitch them like you said and don't waste the time.

None of my AR's require small based dies. When I load for my match BHW, OLY UM's and Shilen AR's none of mine require the SB. YMMV

If I had a batch that just wouldn't size down and I really wanted to use them I'd just trim the top of a shell holder and get more shoulder movement that way. It is a common practice with a set of dies that yielda minimal sizing and a very short chamber. Sometimes you just can't bump the shoulders enough even trying various shell holders and the grinder on the SH is much easier than sending the die back to the manufacturer or chucking it up and taking the bottom off the die in a lathe or milling machine.

Greg

PS: You are certinaly right on those AI guns. That fire forming etc. is not cheap nor is it time saving...LOL

 
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