Howdy all,
Just sorting, cleaning, sizing, trimming, chamfering, primer crimp-reaming all my 5.56 brass from the Davilla AS (yes, a pain in the rear, but with ammo prices these days...) and while I was waiting for the tumbler to finish, I was looking over loads from the Lee and Speer manuals for the 5.56mm and I see that H335 is listed. I have both Varget and H335, but I don't really like the Varget for the 5.56 as it doesn't meter very well in the small-bore case, so I thought I'd like to use the H335 as I have several pounds of it. Anyway, the Lee data doesn't say anything special, but the Speer manual lists 335 as using a magnum primer. So what's the deal? Is the magnum primer really necessary and does it present any problems vs. the standard small rifle primer? I know it will generate a higher pressure, but would it be more sensitive to slam fires than others? Since these loads are going to be used in an AR, I'd like to know! I do have a sleeve of magnum primers, but also have the standards, too. I know CCI makes the mil-spec primers, but if it's safe, I'd like to use up what I have before ordering some. Is this a case of "six of one, half a dozen of the other" or are there really substantial differences between the two primers performance-wise? Anyone with any experience in this area...would appreciate info. Thanks!
The CCI mil-spec (small is No. 41, large is No. 34) uses the same amount of priming compound as their magnum primer, but is less sensitive and requires a harder firing-pin strike as the distance to the anvil is slightly greater.
The standard or magnum CCI should work OK (if you adjust your load accordingly - a max safe load with a standard primer may be too hot with a magnum) as they are not as sensitive or soft as some (like Federal for instance), but for a gas gun I use the mil-spec exclusively for insurance against a KB. Use the others for bolt, lever, and pump actions. YMMV
Good luck, Sir.
Spend the money and get the mil-spec primers. Don't even mess with the others for your gas gun. All it takes is one primer not set deep enough in the mag. Best case, slam fires are a pain, Worse case, somebody gets hurt. Be safe, not sorry. Been there, done that. Not fun.
Here's the "conventional wisdom" on magnum primers.
Use them if the loading manual calls for them, which will normally be:
1. Very large cases, like the Remington Ultra Magnums. Of course, the really big cases often use ...
2. Hard-to-light powders, usually the slowest stick powders and ball, or spherical, powders.
3. Or, for ammo that is expected to be used in very cold conditions, sometimes defined as below zero degrees F.
Loads, especially those near max pressure with standard primers, have to be reduced and "worked up" again when substituting magnum for standard primers. This is good practice with any substitution of components, even powder from a different lot, but especially important in this case. This is wise because there are so many sources of variation, in all the componests a reloader uses, it's a practical impossibility for him to be aware of all of them.
Since magnum primers produce a larger, hotter, maybe slightly longer-lasting flame, they give the powder charge a little faster and more positive light-off, and they can normally be expected to produce slightly higher peak pressures, all other things being equal.
It isn't that standard primers won't make the round go "bang" under those adverse conditions, just that the magnum primers are less likely to produce hangfires, and more likely to produce consistant results in those situations. Or so goes the CW.
My own experience with magnum primers is limited. I've used them as recommended with .357 Mag and .44 Mag revolver loads, per the manual for loads using H110, a "spherical" powder, probably with a good load of deterrent coating on the granules. I don't own any rifles using huge cartridges, and try to avoid exposure to extreme cold. If it's too cold for my ammo, it's WAY too cold for my body. :) :)
The mil-spec primers are distinct mainly because they have thicker or harder cups, to be more resistant to slam-firing. I have no knowledge about the amount/type of priming compound in them. Posts above are undoubtedly right.
Thanks all for the replies. I just found it strange that one manual listed magnum primers as being used for 335 and the other doesn't, even though the charge weights are not all that different. I had understood the CW regarding magnum primers as didactic posted and the loads didn't make sense in light of the fact that the 5.56 is not exactly a large case and I wasn't given to understand that 335 was that slow-burning a powder.
I guess I will just cut out all the guesswork and get some CCI no.41s in the interests of safety. Even though I am a fanatic about my primer seating depth, there's always the minute chance that I miss one and a slam-fire and ensuing KB just isn't worth it. I can replace an AR if I have to, but not my eyes, face or hands! Now I just gotta figure out what to do with all the small rifle magnum primers since I don't know of any large-capacity cases that use small primers and I probably wouldn't run out and buy a gun in that chambering even if I did just to use up some primers. After all, there's other things I need to spend the $$$ on (like an M1A/M14)!
As long as your reloads are within spec then the primer would be fine. I used up all of my "regular" primers for my AR and shot about 1k with out a glitch. Maybe God just looks out for drunks and AR shooters but as long as you are vigilant about checking primer depth you can use up your existing supply and then get NATO spec later or try to trade off to a buddy you has something you could use. I would say NATO spec primers are made to withstand variances of the mass production that military ammunition supplies require. All I know is it worked for me and that primers are getting expensive and somewhat scarce in all my local gunstores so I would not let them go to waste.
Clean the primer pockets (yeah, takes a little time but it's worth it). Seat the primers fully (using one of the little hand held Lee tools its quite easy to tell when the primer bottoms out in the pocket). Use your finger or thumb to check the primer (to make sure it is seated fully while you transfer the primed case to the table, loading block, can, or whatever you will store it in till you put the powder in it. I still do a final "primer feel" before I pronounce it a good reload and put in a box or bag.
Do not allow yourself to be distracted while reloading. TV, talking to someone, etc. can result in incorrectly seated primers, no powder in the case, seating a bullet upside down, etc. Concentrate on that little 50,000 psi pill you're making.
I used what most folks consider the worst primers to use in my M1A for years with absolutely no issues - Federal Benchrest primers. I'll admit I don't remember looking to see if any chambered, but unfired, cartridge had a dent in the primer from chambering. I just know I never had a slam fire.
M1A4ME, you've been lucky, and haven't made any mistakes to lessen that luck. Federal BR Primers are about the most sensitive out there. Good primers, and THE ones to use for a bolt gun.
Folks, most of you should be using CCI or Winchester for use in military semi-autos. They both are the ones least likely to slam-fire.
You don't normally need magnum primers for a non-magnum type caliber. But, some powders are hard to light, especially when cold, and H335 might be one of them (though it is a standard USGI powder, under a different name/number, and they didn't use mag primers).
Burn rate isn't the issue, ignition is. H322/T322 powder is really hard to light when very cold, and that's a possible candidate for a magnum primer. Heavy powder loads (like a .300 Win Mag) is another example.
If you are loading ammo that even might be used in a semi-auto or full-auto firearm, you should be using mil-spec primers.
AFAIK, only CCI offers primers that are advertised, in writing, to be mil-spec; these being #34 and #41 primers. There may be other primers out there that are also mil-spec, but until I see it in writing from the mfr, it's just hearsay.
Here's a link that will explain the whole mil-spec primer business:http://www.cci-ammunition.com/products/primers/primers_prod.aspx?id=30 (http://www.cci-ammunition.com/products/primers/primers_prod.aspx?id=30)
Disclaimer: No financial interest in CCI or any other primer mfr..
the main thing with EITHER type primer is watch your seating depth.....it is time well spent to uniform the pocket, and debur the flashole..seat the primer to the bottom of the pocket, and go shoot..I prefer the hand priming tool by RCBS...it gives you a good feel for total seating...then rub your thumb over the end...with a little practice...you will get good results...lots of manuals list mag. primers for lighting ball powder...I have used both, and really can't say I would buy them just for that most of the time...but as high as things are getting, I sure would not waste a good component either...D-451
One thing to remember is that the CCI military style primers are more like a magnum primer than a standard primer.
The reloading manuals used to say that magnum primers give you a slight pressure increase (don't have a definition for slight) and that the loads with magnum primers are generally not as accurate as with standard rifle primers (don't have a definition for generally not as accurate either).
In your rifle, with your loads, there may not be a perceivable difference, just be aware there could be.
So now we need milspec primers? Hmmmm!
My National Match never saw a milspec primer. Either in the barrel before this one, or this barrel - and this barrel is about gone.
Read that again - that's almost two barrel lives with non "milspec" primers. Have I had hardships due to that? Nah. Problems? Uh-uh.
As far as the 5.56 goes, I've done head-to-head tests with magnum versus standard primers. Those were the ONLY magnum primers I've run through that carbine - all the rest were standard Winchesters. How many standard Winchester primers? I don't really know, haven't kept score - but I do know that I've had this carbine since about '90, and the good trigger job started doubling because I wore out the trigger and sear pin holes.
Read that again - the lower is getting worn out, and I've never run a milspec primer through it.
What has been said before about WHY one would want to use a magnum primer is 100%. In my tests, it just opened up the group, the velocity spread, and the standard deviation. In group size and velocity both.
In general, I won't run a magnum primer. But then, I don't pick powders that need 'em.
I also agree with Bravo, and had not heard of military spec primers
except in recent years. Since the 60s, I have loaded for Garands,
30 Carbines and a Mini 14. Exclusive use of standard primers and
case primer pockets are checked with a simple primer pocket guage
before being primed. Many 1000s of rounds including 45 Auto through
a 1911 A1. Never had a malfunction, but witness a small firing pin
dimple when extracting a fully chambered round when unfired. There must
be other factors such as a not fully seated primer. or a firing pin channel
dirty enough to keep the pin in a forward position. Not sure military
primers would not also detonate the primer under certain conditions.
I'll echo Nickle,,,in general I lean towards Win. or CCi when loading for Semi's.
Bravo makes a good point in that magum strength primers are probably disadvantageous in all but large capacity cases.
That said, right now I'm buying any components I can get a deal on. I certainly wouldn't toss a carton of CCI 450's if I was loading for an AR.
I read a report some years ago regards primer brissance. As I recall it rated CCI standard and CCI magnum as so close in strength as the difference was about moot. It questioned if the different classification was necessary. I believe Win. was rated the hottest. They were developed for ball powder. Then (if I recall correctly) : Fed., Rem. then CCI the 'coolest'. The Sierra site states the Rem. benchrest primer has a good thick cup.
The newer Wolf primer may be worth looking at as well. I've read good reports on it.
If I ever find myself in the 'last ditch', then I'm gonna use what I've got.
FWIW - I've used CCI No. 34's in 7.62 NATO for a couple of years loading match ammo (168 grain SMK, xx.x grains of H4895, Lake City or Federal or GGG brass, 2.800 OAL) for my '14 with good results. I'm happy and will continue to use 'em.
I recently bought an AR15 service rifle. It's very accurate with both Black Hills blue-box 77 grain and PPU 75 grain OTM. Won a local 200-yard reduced course HP match with the Black Hills about a month ago, but hadn't reloaded for this rifle until last week.
This past Sunday after shooting some AQTs with an SKS I went to the 200-yard (short) line as I had loaded fifty test match loads (10 each of 5 different powder charges) for my new stick the night before and wanted to see which one grouped the best.
Using a 6 o'clock hold on an NRA HP reduced 200/600 yard target I found one that consistently grouped 1-inch (two 3-shot and one 4-shot groups in 10-15 mph wind from 10 o'clock) at 200 yards (match conditioned, open-sighted AR15 A2, 20-inch free-floated barrel, 1 in 8 twist, 77 grain Sierra MK, xx.x grains RE15, new Winchester brass, CCI #41 primer, 2.255 OAL).
I'm gonna try them on a casual, fifty round, full distance HP match in Pecos this weekend. They worked good at 200, but I'll find out what they'll do at 300 and 600 yards.
I'm not saying that the Winchester primers aren't better (don't know, haven't tried them, yet), or that the mil-spec primers are necessary in an AR (I do believe in them for my '14, though), just that the CCI 41's in this load show potential. I bought 5K of them a year ago from Widener's at a good price and until they prove themselves otherwise, I'll continue to use 'em.
YMMV.