Small rifle/magnum primers.......

[3006guns]

I posed a question some time ago regarding the use of magnum primers in cast boolit loads, simply because I have a pile of them. Basically everyone agreed just to shoot 'em up.....won't hurt a thing. O.K.....good deal.

Here's a different question on the same note: I have a friend who wants me to load a quantity of .223 j-words for an AR platform rifle he's building. These would not be "hot rod" loads of any sort, just enough to function the action and have some fun, but we've all heard tales of magnum primers increasing pressures (?).

I'm not actually sure if the primer composition is different (doubt it) and more likely the cup is probably just a little thicker, but I'm not sure. Has anyone substituted magnum primers for standard in modest loads, or can you give me solid info as to why it shouldn't be done? I'm taking into account that it's harder to drive a j-word through a bore too.

[Patrick L]

I believe as long as you're not shooting b@lls-to-the-wall loads you should be fine.

My father-in-law, bless his heart, is always picking up either ammo or sometimes components for me in his travels since I reload his Highpower ammo for him. He knows the brands and size I like, but thats about it. About 2 years ago he was very excited that he found a box of CCI small rifle primers during the great shortage. He didn't notice they were magnums. After consulting this board, and since our match load for both the HBAR and his Savage .223 bolt gun is practically a starting load, well below any published max, I just loaded them up and forgot about it. Accuracy and function were fine, and I noticed no difference in where the AR threw the empties, etc. I did mark the ammo in question for easy ID in case an issue ever arose, but none did.

[3006guns]

Thanks Patrick. That's what I was hoping for, some real experience. I'm pretty conservative with my reloading, not just from a safety standpoint but because it's easier on the guns too!

Appreciate it.

[Larry Gibson]

3006

With true magnum SR primers there is a hotter brissance. This is important for consistent ignition if most ball powders are used in the .223, especially in below freezing weather. If the load is worked up, even a "balls to the walls" load, using the magnum SR primer then is quite safe. I have used magnum CCI 450 SR primers or the WSR (made to ignite ball powders) with my standard .223 loads with BLC2, H335, 748, AA2223 and AA2460 since '68. My loads are top end (but within safe psi's) BTW.

Larry Gibson

[3006guns]

Thanks guys....I'm going to forward your info to my friend.

[uscra112]

Just a cautionary note:

The ONLY coherent theory of SEE (Secondary Explosion Effect) that I have ever read suggests that the phenomenon occurs when the primer boosts the bullet out of the case but, due to a light load of slow propellant, the powder charge does not light immediately. When the charge does light, it is faced with a bore obstruction which won't move. We're talking single millisconds here, but that's all it takes.

This was actually lab tested, and the data supports the theory.

A magnum primer will blow the bullet clear more easily, but with your reduced loads you may be on thin ice, unless you use an easy-to-light powder.

Cheers !

[madsenshooter]

Truthfully, nearly all small rifle primers are near magnum strength. Most especially the mil-spec primers, which are also unleaded. All manufacturers are going to this unleaded formula, if they haven't already, you can bet they soon will. The mil-spec primers are designed to fire up ball powders, like Larry was saying above. I use them or regular magnum primers in most all of my cast loads because I feel the pressure wave generated by them make fillers an unnecessary item, especially with the flake powders that I use. CCi #41s are used in all my 6mm-223 loads in my AR. Here's some interesting experiments: http://www.arl.army.mil/arlreports/2006/ARL-TR-3922.pdf

[3006guns]

I read the full post regarding SEE just recently and it seemed to finally explain a problem that has plagued hand loaders for years. If I said "light" charges in my previous post, or led anyone to that conclusion, I apologize. I meant "starting" to "medium" loads using conventional, recommended ball powders.

I've never had an experience with SEE.....don't want to either!

[madsenshooter]

To a lot of neophytes it seems that being able to use this neat acronym to explain any and all pressure excursions is a growing fad. "Got pressure signs, and reduced the load, got an SEE and broke my extractor". Translation: Cracked my extractor with too hot a load, reduced the load and my cracked extractor fell out. Lots of other examples, just seems popular to some to say they had a SEE. But my rifle is OK! I read the article too 3006, I'm just venting a little, tired of hearing about all the SEEs that ain't SEEs.

[Larry Gibson]

Concur wholeheartidly with madsenshooter. SEE is real but not that common. Damage from to hot loads with excessive pressure is far more common and not related to SEE. 3006guns is certainly correct about not wanting an SEE though, I don't think anyone does.......

Larry Gibson

[madsenshooter]

No, not judging from the results I've seen with real ones. Gotta pass. One thing I found interesting in the link I posted above is the pressures generated by a #41 primer, either by itself, with an inert filler or with powder. 2500psi with filler or powder, who'd have guessed?

[bhn22]

Follow the manual & develop your loads carefully. Start at the "starting" loads, and work your way up (or down) from there. Magnum primers burn hotter, and have a thicker cup. Not all rifle primers are the same. Some, like Remington 6-1/2 are not built of heavy enough cups for use in high pressure military loadings, and Remington recommends using 7-1/2 match primers for this. Federal primers are different from CCI primers, and so on. There is no replacement for doing your own load development, with your components, in your rifle.

[AaronJ]

You may also want to check that the primers are compatable with your friends AR. When I got my first black rifle I loaded for it with the same components I used for my mini 14. As a result I had multiple slam fires from the free floating firing pin. Since then I have switched to CCI #41 primers and have not had a slam fire since.

[onondaga]

The most difference I have heard of or seen on a chronograph is a 50-100 fps difference in the .223 when changing from standard to magnum or hot primers. Take into consideration the pressure that is required to deliver 50-100 fps more in a particular load, how that relates to additional grains of powder and that will give you a closer safety guide when changing to magnum primers.

Gary

[3006guns]

Thanks again everyone......and Gary, that's probably the best example I've heard yet. If a magnum primer can boost the velocity that much, we'll stick to starting loads and keep a weather eye out for pressure signs.