primers ??

cooperman223 · July 13, 2009

Does anyone know if there is any difference between CCI 450m small rifle primers and

CCI BR small rifle primers ????

thanks

john.

6BR · July 13, 2009

Does anyone know if there is any difference between CCI 450m small rifle primers and
CCI BR small rifle primers ????

thanks

john.

Hi John

the cci 450 MAG primers have a thicker cup and will stand the pressure better. less cratering and flattening of the primer. and has a hotter flash that will ignite the powder faster then the standard and br primers.

grahamfarmer · July 13, 2009

hi john,

cci 450m are magnum primers as said hotter flash they are usually used with ball type powders where the density of the powder can give variation in burn rates primer example is h380 as most loads for that powder in the speer loading manual recomend a magumn primer .

they are a slightly specilalist primer for a certain task not one you would expect to use in day to day loading. for some powders they are to hot and you will struggle to get results.

the br and standard cci primers are more used in every day work with the br primer surposed to be a better primer in terms of more precise quailty control and hence more consistant results. depending on your caliber and powder combination some people dont find any appreachable difference between the two and some people do so the best advise is to find a load that works with either and then try a different primer only it will show up then one way or other for your circumstances .

mostly for my own reloading i work on cci br primers but carry a few standards as a check point realy but have friends that get tighter groups with standard primers than br or match primers it one of the mysteries of reloading what works for one dont always work for anyone else.

have fun .

graham.

cooperman223 · July 13, 2009

Cheers lads, it looks like its going to be best to try each and see what gives the best results,

many thanks

john.

johnnythefox · July 13, 2009

Thats if you can get hold of any, ive been struggling just lately for br4's

JTF

325WSM · July 14, 2009

Primers are as much a variable component as any other in reloading and can alter velocity and trajectory and therefore accuracy quite considerably.

I have long been an advocate of using primers in the same way as powder to vary a load with great effect.

We dont choose our case because one looks shinier than another but because of the chemical composition that is most suitable for our particular load. Neither do we choose a Powder just because the local shop has it on the shelf and so with Primers - choose your primer to do the best job possible for the load you are generating.

A change of primer can in some loads require a drop of 3 grains and the difference in velocity without any increase in pressure can equally improve by 100fps. Use your primers in the same way as your powder and you will be surprised at the difference your loads will provide.

Here is a basic heat chart - from top to bottom drop about 5-6% in powder and work from there.

http://img.photobucket.com/albums/v356/mry716/Shooting%20-%20other/primerheatchart.jpg

Use it as a guide and add in your own primers when you have assessed them. eg, the Prvi Partizan Primers although burning approximately as hot as the Winchester range do because of their different construction not seem to require a reduction in powder when changing from say Remington. Try for yourself and let us all know your test results as it will expand the above chart considerably.

Use of Magnum primers is normally reserved for the Ball Powders but I am finding I can use them to great effect in the shorter stumpier cases such as the WSM and WSSM range of cartridges. Logically this should also be valid for the Benchrest PPC cartridges.

The same is true for the H4831 SC powder in 243 - A Federal Magnum primer seems to provide anything up to 120 fps higher velocities than standard primers yet seemingly without additional pressure.

BUT

do drop the powder weight and build up again.

In a recent 'Handloader' I notice that Charles Petty has written an article on Primers and 223 accuracy - anyone who would like to read it email me at mry716@hotmail.com and I will send a copy.

Please remember to drop powder weights when changing primers and do also remember that with the present hot weather you need to reconsider all those max loads and take out a little powder.

A 10 degree rise in temp requires a 5% decrease in powder. If we are going to get such varied weather in coming years it may be best to have a min, intermediate and max load to use dependant on weather temperature.

Chris-NZ · July 14, 2009

In a recent 'Handloader' I notice that Charles Petty has written an article on Primers and 223 accuracy - anyone who would like to read it email me ...and I will send a copy.

...

I couldn't care less about this kind offer but the publishers of "Handloader" may not be so appreciative if they saw it...

Chris-NZ