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12/23/2014 8:40:57 AM EDT
Just getting into reloading. I was wondering if I should use full length dies or not. I picked up some rcbs dies made specifically for AR. What is the difference if any than the full length dies.
12/22/2014 11:11:03 PM EDT
[#1]
I've never experienced a benefit from Small Base dies over Full Length dies.

12/22/2014 11:20:52 PM EDT
[#2]
Full length resizing is required for semi-auto and lever action rifles.  If a neck resized cartridge is inserted in a bolt action, the camming action of closing the bolt will force fit the cartridge.  In a semi-auto or lever action, the force used to feed the cartridge is less, which means an oversized case may not chamber properly.
12/22/2014 11:29:11 PM EDT
[#3]
Quoted:
Full length resizing is required for semi-auto and lever action rifles.  If a neck resized cartridge is inserted in a bolt action, the camming action of closing the bolt will force fit the cartridge.  In a semi-auto or lever action, the force used to feed the cartridge is less, which means an oversized case may not chamber properly.
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Also, the shell is being extracted while still hot, elongating it. Depending on how hot the case is, it is possible that a spent shell casing won't fit back into the chamber that it just fired out of.
12/22/2014 11:59:38 PM EDT
[#4]
thank you. What load do you recommend I start with?  I got some hornady 55 gr vmax and some Sierra 55 gr spitzer boat tail bullets. I will be reloading using H335 powder. Hornady has 20.8 gr of powder for 2800fps using a rem 700 26", 1 in 12 twist barrel. Then I go to the AR section of the book and it says to use 24.3gr load for 2800 fps with Sierra 55gr bullet. There seems to be a big difference in data for a 55 gr bullet. I realize the hornady bullets tested were out of a longer barrel so the fps will be greater. The Sierra bullets tested were out of a colt ar 20" 1 in 7 twist.
My ar is a 1 in 7 twist 16" barrel.
12/23/2014 12:47:35 AM EDT
[#5]
Start here:

http://www.ar15.com/forums/f_6/42_Reloading.html
12/23/2014 1:52:13 AM EDT
[#6]
I have loaded 10's of thousands of rounds of AR ammo and have always used only standard full length dies.  Never had a need to use small base dies nor had any extraction problems.  IMHO small base dies contribute to work harden the brass and case cracks.
12/23/2014 9:45:42 AM EDT
[#7]
Quote History
Quoted:
thank you. What load do you recommend I start with?  I got some hornady 55 gr vmax and some Sierra 55 gr spitzer boat tail bullets. I will be reloading using H335 powder. Hornady has 20.8 gr of powder for 2800fps using a rem 700 26", 1 in 12 twist barrel. Then I go to the AR section of the book and it says to use 24.3gr load for 2800 fps with Sierra 55gr bullet. There seems to be a big difference in data for a 55 gr bullet. I realize the hornady bullets tested were out of a longer barrel so the fps will be greater. The Sierra bullets tested were out of a colt ar 20" 1 in 7 twist.
My ar is a 1 in 7 twist 16" barrel.
View Quote


Hodgdon has 23.0-25.3grs on their website for a 55gr projectile.

My rifle likes 24grs H335 with Hornady 55gr fmjbt for a soft plinking load,

25grs behind same bullet is a very common "everyday" load.

As always, start low and work your way up, every rifle is different.
12/23/2014 10:28:27 AM EDT
[#8]
Quote History
Quoted:
thank you. What load do you recommend I start with?  I got some hornady 55 gr vmax and some Sierra 55 gr spitzer boat tail bullets. I will be reloading using H335 powder. Hornady has 20.8 gr of powder for 2800fps using a rem 700 26", 1 in 12 twist barrel. Then I go to the AR section of the book and it says to use 24.3gr load for 2800 fps with Sierra 55gr bullet. There seems to be a big difference in data for a 55 gr bullet. I realize the hornady bullets tested were out of a longer barrel so the fps will be greater. The Sierra bullets tested were out of a colt ar 20" 1 in 7 twist.
My ar is a 1 in 7 twist 16" barrel.
View Quote



 A couple things.

You have referred to "The Book", What book or books are you talking about?  If they are loading manuals, have you read them?  Not just the data section, the whole manual?  If not I would suggest you do so before you load any ammo.

Next, read this.

http://www.exteriorballistics.com/reloadbasics/gasgunreload.cfm

Last, forget Sierra load data. It has not been Pressure tested.  Sierra load data is the only published data I know of that is not pressure tested.  Use reputable pressure tested data and don't forget to check ou the free data from the Powder manufactures/distributors.

http://www.hodgdonreloading.com/data/rifle
12/23/2014 12:04:58 PM EDT
[#9]
Your 16" barrel will be 200 fps slower when that ammo is fired form a 20" barrel, 300 fps slower than a 24" barrel. If you have a chronograph keep this in mind. .223 velocity gains are not linear based on barrel length. Shorter barrels lose more than expected.  

Lots of people are loading 25.0 grains of H335 in .223 when using various 55 grain bullets. This is very close to a maximum load so work up to it. Start no higher than 24.0 grains, increasing the charges in .3 grain increments will help you find the most accurate load in your rifle and allow you to monitor primers and cases for pressure signs.

Never jump right to maximum published data, either online suggestions or in a manual, without cross referencing several sources and starting safely below and easing upwards a little at a time. Good Luck on and welcome to probably the most interesting hobby on Earth.

You will need some type of headspace gage. Drop in gages are the worse, they're better than nothing at all. Buy Hornady's Lock-N-Load, RCBS's micrometer or Mo DeFina's micrometer headspace gage if you want the best tool for the job. .223 shoulders must be set back an absolute minimum of .-003" shorter than there fired measurement for use in a semi-auto. My equipment is set up to move the shoulder back -.004" as an added measure of clearance.
12/26/2014 10:33:50 AM EDT
[#10]
Quoted:
Just getting into reloading. I was wondering if I should use full length dies or not. I picked up some rcbs dies made specifically for AR. What is the difference if any than the full length dies.
View Quote
 Tazmon:  The RCBS die set you bought includes a full length sizer.  You are good to go in that regard.  Full length sizing, while bumping the shoulder back .003 to .004" from the as-fired dimension, is standard procedure for autoloading rifles like the AR-15.  I suggest you pick up a Hornady headspace gage so you can measure the amount of bump-back precisely.  Good luck and keep asking questions as you go. - CW

http://www.midwayusa.com/product/479704/hornady-lock-n-load-headspace-gage-5-bushing-set-with-comparator?cm_vc=ProductFinding
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