The Accurate Reloading Forums
To crimp or not for AR15 ?
18 September 2015, 22:18
Michael b FreemanTo crimp or not for AR15 ?
I am looking at buying dies to handload for my AR15 in 5.56. Redding recommends the set with a crimp function made specifically for the AR15, Forster recommends a die with no crimp function. what do you guys think?
"I will not raise taxes on those making more than 250k"
18 September 2015, 23:34
ted thornI've loaded buckets of ammo for the AR15 rifles
It does not require a crimp.....nor do I use small base dies
I do however collet crimp in station #5 on my progressive because I skip the trimming these past couple years with the AR
10k or more with no issues
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18 September 2015, 23:43
McKayquote:
, Forster recommends a die with no crimp function. what do you guys think?
I personally crimp them in a separate station. But I pretty much crimp everything I load for now. Never use to, always would seat bullets close the the lands and lots of other BS. Now I just seat to the cannelure and crimp on almost everything I load for. I personally feel accuracy of my loads have improved overall.
Mac
18 September 2015, 23:50
Michael b Freemanquote:
Originally posted by ted thorn:
I've loaded buckets of ammo for the AR15 rifles
It does not require a crimp.....nor do I use small base dies
I do however collet crimp in station #5 on my progressive because I skip the trimming these past couple years with the AR
10k or more with no issues
what is the difference with a small base die?
"I will not raise taxes on those making more than 250k"
18 September 2015, 23:56
bigrdp51RCBS makes AR series dies that have a taper crimp and a light crimp can be applied to prevent bullet movment "if needed". That being said I do not crimp my .223/5.56 cases for my AR15 rifles and never had a problem.
If you plan on buying any once fired military brass I would advise getting a small base die to size these type cases back to minimum dimensions.
I like Forster dies with the high mounted expander because they produce the least amount of neck runout.
I'm using the RCBS AR series die for loading my AR15s but I have replaced the expander and spindle assemblies with the Forster unit for reduced neck runout.
Also remember neck tension is governed by neck thickness and the expander diameter and brands of cases can vary in neck thickness.
19 September 2015, 00:24
bigrdp51quote:
Originally posted by Michael b Freeman:
what is the difference with a small base die?
I use a small base die on all once fired brass I buy. My RCBS small base die only makes the case .0005 smaller in diameter than my standard RCBS die but it also sizes a little further down the case.
We live in a plus and minus manufacturing world and chambers and dies vary in size. I have a standard Lee full length die that reduces the base diameter .001 "more" than my RCBS small base die does.
Bottom line, after sizing the case should be .003 to .005 smaller in diameter than its fired size for reliable functioning in a semi-auto rifle. And if buying once fired Lake City brass the cases wants to spring back to its fired size after resizing. Also commercial .223 brass is softer than Lake City and with any type case you want reliable extraction.
I have two AR15 rifles and a Savage .223 bolt action and have five .223/5.56 dies and each die reduces the base diameter a different amount. My recommendation would be to start with a standard .223 die and if needed buy a small base die.
And as you can see below I have all my bases covered.
19 September 2015, 00:48
Michael b Freemanthe Forster looks good
"I will not raise taxes on those making more than 250k"
19 September 2015, 02:03
ted thornBuy what you want but know this.....the AR is easy to load for
Also if you plan on running several thousands of rounds a year through as many AR as we do you will try to cut out extra steps and streamline things
Just a note......I circulate my loads through about 20,000 pcs of
mainly LC brass but also have many othey headstamps that I load
Most all of it is once fired pick up free brass
I load all of my AR rounds on 2 presses that are dedicated to the my families AR rifle shooting habit
Light tumble
Heavy spray lube
Regular SR primmers.....in the hopper
Regular dies.....in the press head
No trim
Lee collet crimp station #5.....because I won't trim AR brass
WC844 powder.....25 grains thrown
55 FMJBT bullets
Tumble to remove lube
By the thousands.....no failures
BTW.....swagging primmer pockets sux but Dillon 600 is the fastest at this task you will ever find
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Maker of The Frankenstud Sling Keeper
Proudly made in the USA
Acepting all forms of payment
19 September 2015, 03:24
dpcdSmall base dies were invented by die makers for those who don't know how to re-load. I have never found them necessary and I didn't start reloading for ARs yesterday.
Crimp? I do, for ARs, slightly, but it ain't necessary. What it does do is turn the mouth into the bullet so it feeds smoothly which is the most important thing it does.
19 September 2015, 07:11
TexKDI pretty much use Redding across the board. So in spite of the excellent quality of Forster I can't comment on that other than to say if the manufacturer recommends it then it probably is good advise on their particular die set.
In the Redding I use the FL die with the Redding carbide buttons in them with excellent results. I also have the small base dies around as you may indeed run in to some cases to use it on.
For the ARs a mild taper crimp helps to keep things feeding smoothly as dpcd offered above. It certainly doesn't hurt anything. Again I use the Redding taper crimp and it works well.
19 September 2015, 08:01
ted thornThe problem with a taper crimp is you must trim to length
If you shoot AR rifles much (1k +) you will abandon trimming
I also DONT full resize
I partial resize for the shortest chamber of all of our rifles....5.56 Nato and Wylde chambers
Never a FTF in our steel bangin
.
.
.
I have one AR that I put together for long range varmints....P-dogs....less than 500 rounds per year here
I use RP brass in it for ease of seperation and only bump the shouler .005 on this rifles rounds
In this rifle I use a single station press and I trim my brass to -.020 1× and never again
Aneal after the first forming then never again
A far cry from a full resize in this rifle and still no FTF
Extraction marks out of this rifle as I run a 27 grn load of Varget under a Nosler 55 grn Varmagedon
We load for the AR by the thousands
+P.....you bet
________________________________________________
Maker of The Frankenstud Sling Keeper
Proudly made in the USA
Acepting all forms of payment
19 September 2015, 08:31
ted thornAbout 5k
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Maker of The Frankenstud Sling Keeper
Proudly made in the USA
Acepting all forms of payment
19 September 2015, 09:39
TexKDI dont disagree with Teds method at all. ^^ And it obviously works.

It is just about how you are set up really.
We just use the Giraud trimmer and it is set to go. It can do a 1000 cases in a fairly short time. I also have the Giraud 223 specific one for a hand drill too. I have the Lee die in the cabinet, just in case, but it has never been used.
Once you have the cases you are going to load cleaned and sized and trimmed then you can just store them until you make a run of what ever volume you choose. Once you get a volume of brass built up then you will have some cases ready to load, some fired, and some loaded in the quanities you choose to work in a batch.
That is just how my set up is.
At the range kids were picking up brass while I was shooting which was fine as they were having a good time. But when I started shooting my best loads, I told them I would give them $5 plus a coke out of my cooler - but all of my Lapua 223 cases go back home with me. The kids got a kick out of it and the Dads understood it too.
20 September 2015, 00:49
df06I've loaded many 1000s for AR 15s, never crimped a single one.
NRA Patron member
20 September 2015, 21:00
SamI've never crimped a rifle round. I haven't been able to pull a 52 to 55 grain .223/5.56 bullet with an inertial puller on my reloads. 77's will pull in an inertial puller but I havent had one move in a magazine.
A bad day at the range is better than a good day at work.
24 October 2015, 05:08
steve4102quote:
Originally posted by Michael b Freeman:
I am looking at buying dies to handload for my AR15 in 5.56. Redding recommends the set with a crimp function made specifically for the AR15, Forster recommends a die with no crimp function. what do you guys think?
I crimp all my Semi-Auto ammo with the Lee factory crimp die.
It not only secures the bullet, it improves accuracy.
This is from Sierra.
Neck Tension When we stop to consider the vigorous (read, downright violent) chambering cycle a loaded round endures in a Service Rifle, it becomes pretty clear it suffers abuse that would never happen in a bolt-action. This is simply the nature of the beast. It needs to be dealt with since there is no way around it. There are two distinctly different forces that need to be considered: those that force the bullet deeper into the case, and those that pull it out of the case. When the round is stripped from the magazine and launched up the feed ramp, any resistance encountered by the bullet risks having it set back deeper into the case. Due to the abrupt stop the cartridge makes when the shoulder slams to a halt against the chamber, inertia dictates that the bullet will continue to move forward. This is exactly the same principle a kinetic bullet puller operates on, and it works within a chamber as well. When the round is stripped from the magazine and launched up the feed ramp, any resistance encountered by the bullet risks having it set back deeper into the case. Due to the abrupt stop the cartridge makes when the shoulder slams to a halt against the chamber, inertia dictates that the bullet will continue to move forward. This is exactly the same principle a kinetic bullet puller operates on, and it works within a chamber as well. Some years ago, we decided to examine this phenomenon more closely. During tests here at Sierra’s range, we chambered a variety of factory Match ammunition in an AR-15 rifle. This ammunition was from one of the most popular brands in use today, loaded with Sierra’s 69 grain MatchKing bullet. To conduct the test, we chambered individual rounds by inserting them into the magazines and manually releasing the bolt. We then repeated the tests by loading two rounds into the magazine, chambering and firing the first, and then extracting and measuring the second round. This eliminated any potential variation caused by the difference between a bolt that had been released from an open position (first round in the magazine) and those subsequent rounds that were chambered by the normal semi-automatic operation of the rifle. Measuring the rounds before chambering and then re-measuring after they were carefully extracted resulted in an average increase of three thousandths (0.003") of forward bullet movement. Some individual rounds showed up to seven thousandths (0.007") movement. Please bear in mind that these results were with factory ammunition, normally having a higher bullet pull than handloaded ammunition. To counteract this tendency, the semi-auto shooter is left with basically two options: applying a crimp or increasing neck tension.Here is an accuracy test, in case you missed it.
http://www.accuratereloading.com/crimping.html24 October 2015, 08:08
tsturmquote:
Originally posted by Michael b Freeman:
I am looking at buying dies to handload for my AR15 in 5.56. Redding recommends the set with a crimp function made specifically for the AR15, Forster recommends a die with no crimp function. what do you guys think?
RCBS dies & a lee factory crimp die.
