Reloading questions from an AR newbie

[Stevenvalleyky]

Been handloading for more than 20 years, almost 40 if you count me pulling the handle with my grandpa at 4 or 5 years old. But I just bought my first AR15 and I know very little about them.
#1, should I expect to have to buy a small base FL sizing die or will the standard .223 dies I bought when they were on sale years ago generally be expected to work?
#2 I never use a cartridge checker and alway plunk test with my barrel. Is plunking a round in the barrel even possible with an AR or is the barrel extension in the way?
#3 I generally cut 1 case mouth vertically for every rifle caliber I load for so I can find the distance to the lands. (Im adding a pic of this so people understand what Im talking about with this one)
#4 What is generally the heaviest and longest bullet I can expect to shoot that will run through Pmags instead of having to single load? Several of the bullets I have looked at over 80 grains say they are too long to run through mags. Can the 75 and 77 grain bullets run through mags or do I have to go lighter? My gun is a 1/7 twist and seems to shoot the 69 gr factory rounds very well but I want to try as heavy as I can go while still feeding through mags.
Any help or advice would be appreciated.

 

[DustyRusty]

I started reloading with 223 and an AR service rifle.

#1 If you have a Wylde or other generous chamber, SB dies most likely not needed.
If it's a match chamber or tight chamber, you might.
#2 It's more difficult with the smaller calibers but I used to do it.
#3 There are many ways to measure distance to the lands. More info on request.
#4 68/69 gn and 75 gn will work in AR15 mags. The 80gn bullets won't and are loaded singularly using a sled.

Your 1/7 will stabilize the 80 grain bullets. just fine. I'd use 68 gn and above.

 

[Blue68f100]

Been handloading for more than 20 years, almost 40 if you count me pulling the handle with my grandpa at 4 or 5 years old. But I just bought my first AR15 and I know very little about them.
#1, should I expect to have to buy a small base FL sizing die or will the standard .223 dies I bought when they were on sale years ago generally be expected to work?
#2 I never use a cartridge checker and alway plunk test with my barrel. Is plunking a round in the barrel even possible with an AR or is the barrel extension in the way?
#3 I generally cut 1 case mouth vertically for every rifle caliber I load for so I can find the distance to the lands. (Im adding a pic of this so people understand what Im talking about with this one)
#4 What is generally the heaviest and longest bullet I can expect to shoot that will run through Pmags instead of having to single load? Several of the bullets I have looked at over 80 grains say they are too long to run through mags. Can the 75 and 77 grain bullets run through mags or do I have to go lighter? My gun is a 1/7 twist and seems to shoot the 69 gr factory rounds very well but I want to try as heavy as I can go while still feeding through mags.
Any help or advice would be appreciated.

Every gun barrel is different, so the only way to know is try sizing one and see if it fits. All my AR's have match grade chambers and I get alone with STD dies, but I anneal every time.

You can use your rifle as a chamber gauge but you will need to strip the bolt to do it. This requires removing the extractor and ejector, a special tool makes this easy but a pita to every time you want to load.

There a many ways to find the max OAL, your mag will restrict you to 2.260" so allow 2.270". Load a dummy round and find out what yours will take. I suggest using the spec max of 2.260"

Depending on what chamber spec you have on your gun will restrict you to 5.56 or 223R pressures. Your 1:7 twist will allow you to shoot heavier bullets and your gun may prefer them over the lighter 55gr and less.

 

[sugarmaker]

75,77 non-VLD bullets will seat correctly at mag length. Must be single loaded if seated out near the lands. The VLD styles will need single loading as the ogive is inside of the case when seated to mag length.

 

[Reloadron]

I really have nothing to add. Loading .223 and .308 for match chambers I have SB dies and over all the rifles I load for I have yet to have any need for the SB dies. I would just start by loading to known published loading data. The Hornady 9th Handbook of Cartridge Reloading has some good dope for loading for service rifle. Bullet weights verse barrel twist has been well covered. That's important and while I have no clue how it might play out for you when I loaded bullets like the Hornady #2249 52 grain Match and ran them in my 1:7 barrel I shot keyhole groups at 25 yards.

Ron

 

[cfullgraf]

If a small base die is available for the cartridge a particular semi-auto rifle is chambered in, that is what I use. I found no downside and it is good insurance against champering problems.

But, if you are resizing cases shot in your rifle, a standard sizing die should work just fine.

If your sizing cases shot in someone else's rifle, you could run into chambering problems. It all comes down to tolerances of the chambers and the sizing die.

 

[AJC1]

The 77 smk was designed as the heavy weight in 223/556. The 77 nossler also works. The 75 Hornaday hpbt works but the 75 eld doesn't. If one wanted a standard for an AR 68/69 grains is good. ...

 

[jmorris]

I use regular dies, not small base and I’m not even sure how many AR’s I have that all run with them.

You can set dies up using this method, however, it’s really a method for a given rifle barrel. If I am loading ammo for use in any/all of them, I use a Case gauge.

Setting size die for AR type rifle.

www.youtube.com

In AR’s, often the distance to the lands will be over mag length.

 

[243winxb]

my first AR15 and I know very little about them.

Good info above. More from SIERRA.

 

[Steve in PA]

I’ve been reloading 223 for both of my ARs for years. All loaded using regular RCBS FL dies. Never once encountered an issue.

 

[JohnMc]

1 - I bought a Lee .223 Rem die set before hearing of the Small base dies. Ammo produced with it has been run trouble free through 4 or 5 different AR-15s and an AR-180b. I don't know what the AR-180b chamber is, but the AR-15s had one Wylde and the rest 5.56 chambers. If the sizing die falls off a boat or some such thing, it'll most likely be replaced with a small base die.
2 - It's easier to plunk with the upper off the lower and visual checking is hard, fingers are good sensory tools.
3 - others have answered this one nicely. My 20-inch 1:8 barreled upper loves 77-gr Sierra Match Kings, FWIW.

 

[41 Mag]

I load for 3 different firearms in .223, and found that if using fired factory ammo cases from each and keeping them separate they work fine.

However, range brass and purchased once fired all go through a SB die due to the varied chambers they might have initially gone through. Trust me when I say, the bolt slamming one into the chamber that is a tad fat, CAN make for a short range day. It is amazing how well they will wedge.

I use the SB for 223 and 308 and 30-06 just out of caution due to having had a locked up round in both semi and bolt actions using surplus or range brass.

As for the bullet weights, I run up to 72gr to 75gr depending upon the bullets. I seat to a functional mag length and that's my determining factor for the 1-7 semi auto. The others have a 1-12 and 1-14 so they get 35 to 55gr bullets and work just fine.

 

[GHinNH]

Regular die will likely be fine, no need to spend money unless it's found a necessity, and why overwork the brass unnecessarily.

There is no definitive answer about cartridge oal, your mags will determine that and likely be different from each other, maybe too much depending on how close you're cutting it. Don't know much about p-mags for 5.56 don't think I've ever had one, I go straight for Lancers.
If you want more, I've found much more wiggle room with steel or aluminum mags than fat overmolded plastic.

Initial "plunk test" and case gauge check are performed, then forgotten in the bottom of a box somewhere. There on out, CBTO of cartridge and bullet ogive is what's important.

 

[Stevenvalleyky]

I appreciate all the responses. I loaded up some range pickup 223 brass with 25.5 gr of BLC-2 with a 68 gr BTHP hornady match bullet loaded to just under mag length. The std dies worked just fine and the rifle seems to be very accurate with that load. Thanks for all the help.