Magnum primers in non-magnum calibers

[Dixie Dude]

Can you use magnum primers in non-magnum calibers if you reduce the power to compensate by about 200 fps.  I've heard that magnum primers increase speed by about 200 fps over a non-magnum.  For instance to avoid compressed load in say a 35 Whelen with R-15 powder can you compensate by using a magnum primer?  I though two things concerning this, one to save some powder, and two to increase speed if it doesn't overpressure. 

[wncchester]

Can you do it?  Sure.

Will it do what you want?  Who knows?   Try it.

[Siskiyou]

I experimented, using Magnum primers in the 270 Win and H4831.  I did not run into any issues.  I did it to increase my knowledge base loading for the 270 Winchester.  I have not followed up in every day usage. 

Note that Speer Manual #12 shows CCI200 primers (Standard Large Rifle) and CCI250 primers (Magnum Large Rifle) are used for the 270 Winchester, with the magnum primer being used for ball powders and the slowest burning powders.

When using Winchester-Western primers with ball powder I used Magnum for magnum cases and standard for the 270 Win., 30-06, and smaller cases

[BCB]

I would be surprised if the velocity increases by 200 fps...

But who knows?...

I have an excess of CCI-550's and I use them in every 357 Magnum and 38 Special load that I shoot.  Never really saw any difference as I use them right from the start of load development...

Good-luck...BCB

[Catfish]

Last summer when I had little to do I tested different primers in different rounds with different powders. What I found was that depending on the powder used the primer could increase velocity, decrease velocity or have exactly the same velocity. The way the primers reacted was totally dependent of the powder used. I would load the same load with several different primers and crono 5 shot strings of each primer. All I can tell you for sure is that you need to start working up your load every time you change primers. I could find no rime nor reason for the way they reacted.

[huntducks]

Last summer when I had little to do I tested different primers in different rounds with different powders. What I found was that depending on the powder used the primer could increase velocity, decrease velocity or have exactly the same velocity. The way the primers reacted was totally dependent of the powder used. I would load the same load with several different primers and crono 5 shot strings of each primer. All I can tell you for sure is that you need to start working up your load every time you change primers. I could find no rime nor reason for the way they reacted.

SAME HERE.

I use mag primers to increase accuracy I have never run into 200fps maybe 20 to 30 at most but that is just me.

[chutesnreloads]

Add to that every gun will be different.Changes or not in one gun will be completely different in another.

[Land_Owner]

Since when did magnum primers become synonymous with magnum calibers???  That is a misnomer as there is no relationship between these two whatsoever. 

What is known is that a primer is required to ignite the powder.  Which primer to use is PUBLISHED by the bullet/powder manufacturers.  When deviating, reduce PUBLISHED LOADS, then start the accuracy process again.  Deviation from published loads is AT YOUR OWN RISK.

[roper]

Can you use magnum primers in non-magnum calibers if you reduce the power to compensate by about 200 fps.  I've heard that magnum primers increase speed by about 200 fps over a non-magnum.  For instance to avoid compressed load in say a 35 Whelen with R-15 powder can you compensate by using a magnum primer?  I though two things concerning this, one to save some powder, and two to increase speed if it doesn't overpressure. 

When I started reloading the manuals only list primer size.  I used mag primers in some caliber and I work up loads the same as using a non mag primer and I think Speers manual has making by powder that require a mag primer in standard calibers.

Most everything I use mag primer in is a custom and throated for certain bullets so I don't run into compress loads and in my 35 WhelenAI I see maybe 20/25fps increase with fed 215 over 210 using R-15 with 225gr AB.

Not sure what bullet your using in a 35 Whelen but if you look ar Nolser manual # 6 the difference between start load with R-15 with 225gr bullet and max load is 91fps and the 250gr bulet is 174fps and the amount of powder is 4gr between start and max.  What your trying to do is use a start load with mag primer and get same velocity as max load or more.  I'm not poking fun at you but your not the first to come up with that idea nor will you be the last.

If you look at all the data then look at the primers do you honestly think 200fps gain is possible and if it was everyone be doing it and you see a whole new set of reloading manuals.  there was a study done by NRA on primers forget which caliber they used but a gain maybe 20/30fps and 5/6kPSI gain so you really need to be careful.

[FW Conch]

I use magnum primers for ball powders, for use in cold weather, or whenever suggested in the loading data.  A few years back, during a primer shortage, the only thing I could get was magnums.  The guy @ the counter was a reloader & said he "always" used mags anyway.  So I tried them, & without "cronoing" them, I couldn't tell the difference.

I agree with roper - I seriously doubt a 200fps increase.  - Jim

[Dezynco]

Generally speaking, magnum primers are used in combination with powders that tend to be a little harder to ignite, thus giving the cartridge a cleaner, more thorough burn.

However, I've noticed that they are also recommended occaisionally for compressed loads that have the powder squashed down tightly against the flash hole.  I have also seen them used in super-light "plinking loads" that do not have a lot of powder in the case.  I've never noticed them recommended to increase muzzle velocity, and if they did increase muzzle velocity, it wouldn't be much.  Certainly not worth the extra expense.

In Black Powder Cartridge Rifles, there has always been a debate about which primers to use to get the best groups down range.  I think that Mike Venturino wrote in his book "Buffalo Rifles of the Old West" (I think that's the title?) that he got the best consistency from - believe it or not - Federal Large Pistol primers in his rifle cartridges.  Go figgure!

[roper]

Two things to always remember when changing primers etc is shoot over a chronograph and load smart not dumb.

I build a 280AI has a 27" long barrel and I also load at the range.  Nolser has reloading data for the 280AI using IMR-7828 using Fed 210 primers and that barrel used in the test was 26" long.

My start load was  same as book 160gr AB 57.5gr/IMR-7828 with fed 210 2916fps book was 2856fps I moved  up to 58.5gr @ 2946fps book had 59.5gr @ 2950fps I moved up to 59.5gr @ 3038fps book had 61.5gr max load @ 3043fps.  I stopped loading

Next I switched primers to mag primer Fed 215 57.5gr/IMR-7828 @ 2915fps moved up to 59.5gr @ 2991fps I stopped as I gained nothing going with the Fed 215.


I'm lucky in that I can load at the range got to be  careful changing things  never know what really happening.

[carbineman]

I use magnum primers for ball powders, for use in cold weather, or whenever suggested in the loading data.  A few years back, during a primer shortage, the only thing I could get was magnums.  The guy @ the counter was a reloader & said he "always" used mags anyway.  So I tried them, & without "cronoing" them, I couldn't tell the difference.

I agree with roper - I seriously doubt a 200fps increase.  - Jim

Dittos All I normally use are magnum primers though I use some Remington 9 1/2 and WLR for some 7.62x39mm loads. When they are gone I'll probably just use the 9 1/2M's I use in most every load. I use mainly ball type powders.

[necchi]

I wonder how many know a Magnum primer isn't "Hotter", ?

[AtlLaw]

Maybe now would be a good time for someone to post those primer test photo's... 

[Dave in WV]

Swithching to a magnum primer may cause an increase of pressure and maybe a slight increase invelocity but 200fps seems like a big increase to me.