Large Rifle primers with slow burning powder?

[Chris Butler]

A buddy asked me to help him develop a round for his 338 Lapua Magnum
I have 300gr Hybrids, H1000, IMR 8133 and Retumbo to work with.
He only has large rifle primers. No magnums.
Are these going to be hot enough to ignite the 8133 and Retumbo?

 

[rhovee]

I wouldn’t. Might work on some days but not all. If your in WA, send me a PM and I’ll set you straight with some large rifle magnum

 

[ebb]

NO

 

[painter]

If you are In WV PM me.

 

[centershot]

That's what I like about this forum! ^^^^

 

[DRNewcomb]

You could always run a test batch an see what affect regular primers would have but I suspect there's a reason why some powders call for magnum primers.

 

[bozo699]

You could always run a test batch an see what affect regular primers would have but I suspect there's a reason why some powders call for magnum primers.

I have ran them in smaller magnums with ok results during the last shortage of primers but that’s a huge volume of powder he’s trying to light off ,... I would be Leary of it especially in cold weather as others have suggested I would opt for swapping with someone
Wayne

 

[ebb]

A gunsmith convinced me to try Federal GMM LR in a 7mmRUM extreme spread was over 50, magnum primers were single digits. They came out with these for a reason. I can not even understand why people want to try, sooner or later the temperature or altitude is going to bit you when you need it to work.

 

[Trooper836]

Where are you located? I am in Kentucky.

 

[243winxb]

https://www.shootingtimes.com/editorial/ammunition_st_mamotaip_200909/100079

Starting & mid-range powder charges may have a problem with standard primers. I would guess it all depends on the type of powder.

 

[asmugn]

I also find myself in this situation - reloading for 300 Wby and could only acquire large rifle, not magnum, primers. I have 1000 wolf primers if anyone would be willing to swap with me. I'm in Fredericksburg, VA but frequently return home to Lexington, KY - anywhere along that I-64 corridor is do-able for me.

 

[Chris Butler]

Thanks for all the replies
I'm in Western Wyoming
I appreciate the offer for primers.
I have magnum primers for my loads.
I guess I will have to break into my stash for him
Much appreciated!

 

[Woofie]

There is an article and link elsewhere on AccurateShooter called "Primers - What you need to know". Worth the search and read. I believe the author is/was a ballistician at the old Speer company.
This is the extract that I thought may be responsive to your question: (bold italicization mine)
"Magnum Primers: Use As Directed
Most primer makers offer a standard and a Magnum primer in each size and application. The Magnum primer offers more power for challenging ignition scenarios. A large-capacity case, a heavily deterred propellant, or extremely cold weather (less than 20 degrees Fahrenheit) typically makes the Magnum primer desirable.
There are two ways to make a Magnum primer — either use more of the standard chemical mix to provide a longer-burning flame or change the mix to one with more aggressive burn characteristics. Prior to 1989, CCI used the first option in Magnum Rifle primers. After that, we switched to a mix optimized for spherical propellants that produced a 24-percent increase in flame temperature and a 16-percent boost in gas volume.
Literature from some propellant manufactures often says that their products do not require Magnum primers. This is perceived as a good thing because Magnum primers are made in smaller quantities and require more chemicals; therefore, they are more expensive. However, I had to take a different view, one based on real-world issues.
We tested loads at both maximum normal pressures and at the starting loads (some labs calculate start loads — we shot them). Standard primers caused no ignition issues at the max load but posted higher extreme variations in pressure and velocity in the lower pressure regimes of the start loads. In extreme cases, the start loads produced short delayed firings — probably in the range of 20 to 40 milliseconds but detectible to an experienced ballistician. Switching that propellant to a Magnum primer smoothed out the performance across the useful range of charge weights and completely eliminated the delays.
If I've recommended a Magnum primer in reloading data I've developed, it's because my lab results show it's needed."

 

[Chris Butler]

There is an article and link elsewhere on AccurateShooter called "Primers - What you need to know". Worth the search and read. I believe the author is/was a ballistician at the old Speer company.

Thank You
Much appreciated!
I will definitely read this