375H&H - Magnum Primers?

With more than 50 grs powder and/or powder more progressive than RL17 / Norma URP I use always magnum primers.
 
Tall powder column or hard to ignite powder, magnum primers. YMMV.
 
possibly where the first advantage for mags will be noticed is in really cold conditions with powder 4350 and slower.
it is said that win ball powder can need hotter primers than say imr stick powder, and that win primers reflect this.
bruce.
 
This thread reminded me that my most accurate load in my brief High Power Silhouette career used a Remington 2 1/2 (Large Pistol) primer in my .308. 42gr of IMR 4895 pulled from Chilean surplus ammo and a 180gr Sierra BT.

Sometime a milder primer will shoot more accurately than a hotter primer.

But for hunting loads, I'll take 5% better reliability over 10% better accuracy, most any day.

Yeah, I pulled those percentages out of my butt. But you get my point. This would be especially true if hunting in colder climes where the thermodynamics are working against you.
 
tarbe,
your post reminds me that pistol primers often shoot better than rifle primers in black powder cartridge ammunition.
in fact putting a paper wad in the bottom of the primer pocket can be even better again.
however black powder ignites far easier than smokeless, and cannot produce the same pressures.
bruce.
 
Would a non mag primer cool down a load slightly?
 
not necessarily, but possibly.
worst case scenario, in a really big case with slow burning powder it could produce a secondary explosion effect and blow your gun up.
bruce.
 
Right then.

Cheers guys, seems the concsensus is broadly magnum then. Good to know, I've got loads of them!

Does anyone have any experience with N150? THe Viht data is a bit anaemic versus every other source I've seen and I'd rather not waste 20 odd shots working up from the bottom of their ladder if they're starting at 2,100fps or whatever.

Cheers!
Al.
 
Right then.

Cheers guys, seems the concsensus is broadly magnum then. Good to know, I've got loads of them!

Does anyone have any experience with N150? THe Viht data is a bit anaemic versus every other source I've seen and I'd rather not waste 20 odd shots working up from the bottom of their ladder if they're starting at 2,100fps or whatever.

Cheers!
Al.

Ammoguide.com lists 175 loads for the .375 H&H, eight of them with N-150.
 
Sounds like there is no reason not to use the magnum primers.
No mention of the Aussie ADI powders.
Im interested if anyone can elaborate. my only magnum is .375H&H . I might get another .300wm or maybe a 7mm Rm
 
not necessarily, but possibly.
worst case scenario, in a really big case with slow burning powder it could produce a secondary explosion effect and blow your gun up.
bruce.
possibly where the first advantage for mags will be noticed is in really cold conditions with powder 4350 and slower.
it is said that win ball powder can need hotter primers than say imr stick powder, and that win primers reflect this.
bruce.

CBH
apart from the above.
adi powders can be checked on various burning rate scales, with ar2209 being about the same as imr 4350 etc.
bruce.
 
Thanks bruce moulds
I have ADI powders in my cupboard but currently using some PPU factory loads to collect shells.
I wont be going anywhere thats too cold. We dont have bear in Australia. If ever im lucky to hunt bear i might brave the cold.
 
So I finally, finally had a chance to play with the new acquisition today at the range.

It's the biggest calibre I've shot in any quantity, excepting the odd go with other peoples rifles and it's certainly a different experience.

As it stands, the N150 loads are very accurate if I do my bit, although the viht data is, as suspected, on the low side with some smoky cases seen on the lower ends and nothing breaking 2,400 even at the top, so I'll be progressing on up the charges a bit further next time.

The other learning is around my recoil tolerance. Whilst I've shot a bit of 375 off hand and sitting in the past I've never done load development off the bench with one before.

The first 10 rounds were fine, but after that, a bit of a flinch started making itself known and the groups opened up.

I'd say in the future I'll have to limit myself to strings of 5 and maybe 20 max over the space of a day split up with some milder stuff in between if I'm to avoid bad habits. Still, no great hardship and its certainly good fun off hand.

A bt more development with the Gamekings, some work with the TSX and I'll have practice and competition ammo sorted for next year. After that, some time on the running boar range and then a trip to the continent for driven game beckons!

Al
 
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I've only used magnum primers (215M) in my magnum calibers and large rifle in my non-magnums. Why? Because that's what the manual say, no other reason.

My Modern Reloading by Richard Lee second edition says to only use magnum primers when load data calls for it. 375 h&h, 458 win mag and most of the other magnum cartridges specify standard large rifle primers not magnums. Only 300 rem ultra mag, 338 marlin express and 338 lapua call for magnums. Even the 460 wby mag calls for standard large primers. In my nosler manual it's the opposite.

Hearing the talk of the need for magnum primers I was very surprised to see this. I wonder if Lee has a reason for doing this?
 
In us most of our hunting is done in colder climate. Magnum primers makes sense for safety of proper ignition when load density is on the border line.
 
I have been loading RL22 for my 7mm RM. In load development I have used both LR and LRM Remington primers. I could not tell the difference, except the LR primers produced very slightly smaller groups. I will stay with the LR primers.

That said, the 375 H&H has a rather long powder column. I notice that at least two load data reference (Woodleigh's and Lee's Modern Reloading 2nd Ed.) do not include a primer type for their load data. These both seem to be aggregations of previously published data from other sources. The Norma Guide I have specifies Win LR MAGNUMS for all rifle loads listed - even small .308 Win. based cases. A bit confusing. Perhaps there is little difference between the LR and LRM - burn rate? Temperature? I don't know.
 

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