# Small Magnum Primers (CCI 450s)



## Bax* (Dec 14, 2008)

Does anyone know how much difference a small rifle magnum primer (CCI 450) makes as opposed to a standard small rifle primer? Outside of different cup thicknesses, I am assuming that they might burn hotter but am wondering if it is all that different as to cause noticeable pressure differences?

I am asking because I noticed that I accidentally purchased one small package of CCI 450 primers some time ago (because some turd put it in a box of 1000) and didnt have much use for them. However the Speer manual says that I can use it for a .223 Rem in conjunction with H335 powder (which powder I have already), but the Nosler and Hornady manuals just suggest regular WSRs and Fed 205Ms with H335.

Has anyone used this primer for their 223?


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## mikevanwilder (Nov 11, 2008)

I have a cousin who uses it in his 223 with alot of success, he shoots the Hornandy V-max. I think in 40 or 55 gr not sure but he has got it pretty dang accurate.


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## DallanC (Jan 13, 2009)

I posted a primer hotness chart on here a while back... search for it.


-DallanC


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## Bax* (Dec 14, 2008)

This is the only one I could find DallanC, and I actually searched this specific topic out before I made this post because I remembered you posting this: viewtopic.php?f=15&t=21136&p=233877&hilit=+primers#p233877

I cant seem to find out much about these primers to see how useful they would be for me


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## DallanC (Jan 13, 2009)

Yep, thats it. I dont have that info on my current computer so I couldnt just repost it. Glad you found it here though 

IMO, primer is the last thing to tweak when handloading.


-DallanC


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## Bax* (Dec 14, 2008)

DallanC said:


> Yep, thats it. I dont have that info on my current computer so I couldnt just repost it. Glad you found it here though
> 
> IMO, primer is the last thing to tweak when handloading.
> 
> -DallanC


Agreed. I think my root question is how will this primer affect my load as opposed to a standard small rifle primer? I didnt see the 450s on your post, so thats why I asked the question


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## Frisco Pete (Sep 22, 2007)

You might want to back off by 1.0 grain or so and work back up. Load up some test loads at 1.0 and 0.5 grains under your current load - then some at your current load level and watch for pressure signs or chronograph to see how velocity is affected. You may have a different accuracy "sweet spot" because of the primer change.

I found it interesting that Speer uses 26.0 grains of H-335 with a 55-gr bullet and the CCI 450 magnum primer. Most data sources don't go as high as 26.0/H-335/55-gr bullet with any primer. I think the individual rifle will dictate how things go.

Both the Winchester WSR and Fed 205 are considered "standard" brisance primers, while the CCI 450 is ranked as a "magnum". It uses the same 0.25" cup thickness and primer compound as their #41 mil-spec primer.
The WSR has a cup thickness of 0.021" and the Fed 205 0.0225" so the CCI 450 definitely has a more mil-spec resistance to slam fires and piercing issues and more pressure-tolerance.
I know that the CCI 450 is very popular among AR15 reloaders and is rather well-thought of.

Extruded powders, such as relatively small-grained 4895 or large-grained H-4831 depend mostly on granule size to control burning rate. Ball powders don’t vary much in granule size, so depend mostly on relatively flame-resistant exterior coatings to control burning rate. By definition, these coatings make ball powders harder to ignite. That is why Speer recommends the CCI 450 for igniting ball H-335.

There also is an unusual situation that should be considered when deciding whether to use standard or magnum primers with ball powders that is pointed out in the Speer manual: Powder manufacturers may state that their propellents do not require magnum primers. This is generally true at maximum safe pressure levels. But Speer’s ballistic testing fully explores propellent behavior over the usable range of charge weights. They often found that a particular propellent works fine with standard CCI primers at the maximum safe pressure. However it may not consistently ignite with lower charge weights. In the lower pressure regimes typical of “starting loads” they commonly saw increased extremes of pressure and velocity. Some ball powders ignited by standard CCI primers will even produce short hang-fires–called “click-bangs” for obvious reasons–at start load levels but not at maximum safe pressure. In those cases the use of magnum CCI primers to insure performance over the range of charge weights is recommended.
In addition cold weather ignition of certain powders is usually more consistent with a hotter spark from the primer.


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## Bax* (Dec 14, 2008)

Thanks for the info Frisco

sometimes you and DallanC amaze me with the information you produce.

So, because the 450s are hotter than a standard small rifle, would it be safe to assume that this primer is not for just any powder?


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## Frisco Pete (Sep 22, 2007)

No, you can use them for any powder. You just need to work up to max or where the accuracy is good like you do with any component change. I don't think they are a huge amount hotter than most standard primers.

Playing around with primers can change your accuracy. For example, switching from the Win WSR primer to the Rem 7 1/2 BR primer in my .223 Rem H-335/55-gr bullet load picked up a solid 0.25" better grouping at the same powder charge weight. So sometimes it pays to experiment. 
Anymore with primer shortages being a possibility at random times of panic buying, you probably should know which primers perform how beforehand in your pet loads in case you have to switch.

I did produce a rather extensive primer info thread on another gun forum, so I have done a lot of research. That is why I know a lot of this trivia. 
http://www.sksboards.com/smf/index.php?topic=56422.0


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## Bax* (Dec 14, 2008)

Thanks again for all of your insight Frisco 8) 

Sometimes I am awestruck by the knowledge you guys have on these topics.

I, being a young punk, have much to learn and have picked up a wealth of knowledge over the past several months from you guys.

Thank you for being willing to share your knowledge


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