UGH, another help with primers question

[DMTJAGER]

My apologies as I know this question has likely been asked here multiple times previously and answered, but multiple searches here didn't turn up any helpful info so I am going to ask for the help of those more knowledgeable at reloading for 223/556 AR's than myself.

A little background about myself. Been reloading for over 30 years and in that time have made 1k's of HG and rifle loads. Although I have owned AR-15's for almost 10 years now I've never reloaded for them or any semi-auto rifle. There were quite informative sections in several of my manuals about reloading for semi-auto hunting rifles and I thought that information was good enough if applied to reloading for my AR-15's. I did reload for my friend who owned a 223 16" T/C Contender years ago and have several thousand CCI 400 small rifle primers. I knew one day I most likely would have to reload for my AR's so I gradually built up my stores of 55 and 62 grain FMJ bullets along with great metering 223 powders like TAC, CFE 223, AA2230 and a few others.

Like any good reloader before I bought any primers or powder to reload 223, I consulted all seven of my reloading manuals (Hornady, Speer, Sierra, Lyman, Hodgdon, Nosler and Lee) to compile data and reach a consensus on what powder and primers best suited my needs to reload for 223. Based on my manuals suggestions over the last 5-6 years I stockpiled CCI 400 primers, Winchester and Federal non-magnum, small rifle primers and Federal magnum small rifle primers.

I also have and use the newest version of the Hornady LNL AP progressive press and have enjoyed excellent success reloading 9mm with it. Now that I wish to start reloading strictly plinking range fun ammo I again consulted my manuals. Then it occurred to me that all of the reloading information for 223 was strictly for bolt action rifles and no semi-auto hunting rifles and none of my manuals even so much as mentioned reloading for the AR-15 platform of rifles. This might be due to the fact none of them had a print date any newer than 2004. I then remembered an EIGHTH reloading manual I owned titled "Precision Shooting Reloading Guide" by Davis Brennan and it had an entire section dedicated to precision reloading for high powered gas operated service rifle competitive shooters.

While reading through that manual I came across a problem for semi-auto service rifles like the M1 and M14 and although rare compared to M1's and M14's also the AR-15 platform called a "slam fire" that could have disastrous results for the rifle and possibly the shooter as well. The manual said no conclusive cause for slam fires in in service rifles had ever been determined. It also never suggested strictly using magnum small rifle to reload for AR-15's and said both regular and magnum SM rifle primers worked well. It did mention that there was thought that Federal primers had to thin a cap and that was likely the cause because most of the hang fires were occurring with federal primers. But Federal published data in an issue of the magazine "Precision Shooting that refuted the notion their cups were any thinner or weaker than anyone elses, and cited the fact federal primers were by far the most common primers in use by people reloading for service rifle comp shoots as why thier primers were experiencing most of the hang fire incidents.

I felt considering this manual was written in 1995 the internet might offer me a better explanation for the cause of "slam fires" in semi-auto service rifles. So I did a search and what I found was people stating that using non-magnum small rifle primers like CCI 400 non mag SRP have thinner cups VS magnum SRP and are the main cause for hang fires in the AR-15 when combined with the fact the AR-15's firing pin is free floating is the cause of slam fires.

These same people went on to say to avoid hang fires you should NEVER reload 223 for use in a AR-15 using standard non-magnum small rifle primers and should ONLY use magnum small rifle primers or risk a hang fire. This is a bit of a problem for me considering about 70% of my small rifle primers I bought specifically for reloading for my AR-15 are standard non-magnum small rifle primers.

So is this true concerning small non-magnum rifle primers as the primary cause of hang fires for AR-15 reloads or not?

Thanks,
Arthur.

[DG23]

So is this true concerning small non-magnum rifle primers as the primary cause of hang fires for AR-15 reloads or not?

Thanks,
Arthur.

Your CCI 400's will be fine with .223 pressure level loadings. If you start experiencing slam fires with them something is wrong with your rifle or reloading methods.

I prefer CCI 41's for hotter 5.56 level loadings.

[bigedp51]

For the M16 and AR15 it is recomended that primers with a cup thickness of .025 be used to prevent slam fires.
NOTE, When Remington ran Lake City the 7 1/2 primer was used in all 5.56 ammunition.

During trials testing both the M14 and M16 rifles had their firing pins lightened to lower their inertia. This greatly lowered the chances of a slam fire even when loading a single cartridge.

The greatest chance of a slam fire is when a single round is loaded without the magazine in the rifle. When the cartridge is fed from the magazine it slows down bolt velocity and firing pin inertia. Most slam fires are caused by primers that are not seated flush or below with the base of the case. (high primers)

READ THE ENTIRE LINK BELOW ON PRIMERS


Primer Info & Chart + Milspec Primers for Semi-Autos & Other Primer Applications
http://www.sksboards.com/smf/index.php?topic=56422.0
CHOOSING THE RIGHT PRIMER - A PRIMER ON PRIMERS

Small Rifle Standard

CCI 400 -thin .020" cup, not recommended for AR15 use by CCI/Speer. Good for .22 Hornet, .30 Carbine. See Note 1 at the bottom of the page
CCI BR4 - match primer with a thicker .025" cup.
Federal 205 - Mil-Spec cup thickness according to Federal - okay for 5.56mm. .0225" cup thickness.
Federal 205M - same as the 205 but the match version.
Magtech PR-SR - .025" cup thickness (not much feedback yet on this new primer as to AR15 suitability but with the same cup thickness as the Rem 7 1/2 it looks good so far)
Remington 6 ½ - thin .020" cup, intended for older, lower pressure rounds Remington says do not use for the .223 Rem or other similar pressure rounds. Good for .22 Hornet, .30 Carbine.
Remington 7 ½ BR - A match or "bench rest" primer. Lyman & Nosler classify this primer as a Standard. Remington says the compound is the same as the 6 1/2 but with a thicker .025" cup.
RWS 4033
Winchester WSR - some piercing issues noted when changed from silver to brass cup. Cup thickness is a bit thinner at .021". Most say they are good to go for the AR15 despite that, probably because of the hardness of the cup. Some feel they are less resistant to higher pressures.
Wolf/Tula Small Rifle SR #KVB-223 - soft, sensitive copper cup, not recommended for AR15/military rifle use or high pressure rounds.

NOTE 1: According to Speer/CCI Technical Services - Both the CCI 550 Small Pistol Magnum and CCI 400 Small Rifle primers are identical in size. Both primers use the same cup metal and share the same cup thickness. Both primers use the same primer compound formula and same amount of primer compound. They can be used interchangeably.

CUP THICKNESS

Different primers have different cup thicknesses. You can see the importance of cup thickness when primers are considered for semiautomatic rifles that have free-floating firing pins. This topic is discussed in greater detail in the post "MILSPEC PRIMERS FOR SEMI-AUTOS FAQ AND INFO" that follows the primer chart.



The CCI #41 primers have a thicker cup in the base and the anvil is shorter giving added insurance preventing slam fires. BUT the Remington 7 1/2 primer was used at Lake City until Winchester took over in 1984 without any problems.

[markm]

So is this true concerning small non-magnum rifle primers as the primary cause of hang fires for AR-15 reloads or not?

Not. There's so much brainless reloading dogma perpetually aped, it's exhausting.

[TomMcC]

Total BS. I've loaded thousands of .223 with everybody and their brother's standard primers and NEVER had a problem. I did have many hang fires with Wolf primers and I believe was H335, but never with CCI, Winchester, or Federals.

[bigedp51]

Are you asking about slam fires or hang fires????????


Below is a hang fire from a British .303 Enfield rifle and old surplus Pakistani ammo and what happens when you pull the trigger and hear a click and open the bolt before the "bang".

[DMTJAGER]

My apologies I meant SLAM FIRES not hang fires. I own and shoot 5 different muzzleloaders (three inlines and two T/C Hawkin side hammers) which are subject to hang fires, so sorry I confused the two.

Thank you all for your sharing with me your exceptionally impressive knowledge of primers and AR platforms. As I said I am a AR platform novice but have been reading all I can get my hands on since i bought my first one. I know a good deal about the history and development of Eugene Stoners ingenious design and how it works and about the myths, misconceptions and untruths that plaque this great rifle design. I am just now trying to learn about how to reload for it as this will be the first service type semi-auto rifle I ever reloaded for. I have done some reloading for a Browning BAR hunting rifle in 7mm RM and a Remington 7400 in 30/06 both for friends, but that was over 15 years ago and only on my single stage Rockchuker presses as I own two.

So this will be a completely new reloading experience for me especially since I am going to use my Hornady LNL AP press.

Thanks again for the great advice and sharing of knowledge with me. You have definitely furthered my AR-15 education and knowledge base.

[TomMcC]

You won't have slam fires either. I don't think I've actually even heard of a slam fire with an AR using standard primers. Supposedly an M1 or M1A can slam fire if you drop a round in the chamber and then release the bolt, but I think even that's a bit overblown.

[DG23]

Based on my manuals suggestions over the last 5-6 years I stockpiled CCI 400 primers, Winchester and Federal non-magnum, small rifle primers and Federal magnum small rifle primers.

.

I was doing pretty much the same when I started. A few k here and there of whatever SRP I could find and afford at the time. Over time it did build up but it built up with a bunch of small amounts of different brand primers.

It stinks to work up a really good load with particular components and then realize you only have 2k of those particular primers...

When I started buying the primers in the big boxes so I could be working from the same lot number primers for a good while the smaller lots of misc primers got designated for pistol use to use them up and get them gone.

[markm]

Total BS. I've loaded thousands of .223 with everybody and their brother's standard primers and NEVER had a problem. I did have many hang fires with Wolf primers and I believe was H335, but never with CCI, Winchester, or Federals.

Same here.