LR vs SR vs SRM.....

[NSP64]

If I have a load that shoots good in a case that uses a LR primer, and I switch to a different case (same size) that uses SR primers, Should I use Small Rifle Magnum primers?? It seems that the use of SR primers just does't have enough umpfff.

[S.R.Custom]

What cartridge are we talking about? Is it a case crammed full of slow burning, hard to light ball powder? Or 4.0 grains of Unique?

[mike in co]

the only common place i know of it 7.62x39.
rp makes three different headsamps for this round and ONE of them is sr, all else is lr in commercial ammo.( 220 russian/6ppc is a diff story)

mike in co

[StarMetal]

mike, apparently you forgot the 6.5 Grendel...it has large and small rifle primers too. Not sure but isn't there a 6.8 that has small rifle primers?

Joe

[NSP64]

A case full of slower powder. I don't know if the SRM is equivical to a LR primer.

[mike in co]

mike, apparently you forgot the 6.5 Grendel...it has large and small rifle primers too. Not sure but isn't there a 6.8 that has small rifle primers?

Joe

joe,

ohh, i was talking about COMMON rounds.......(lol....ducking)

yes 6.5 has a following, but isn't the 6.8 running away from it ?( that is a question, not a statement). i do sell stags, and have sold two of the 6.8's in the last couple of months.


mike in co

[S.R.Custom]

mike, apparently you forgot the 6.5 Grendel...it has large and small rifle primers too. Not sure but isn't there a 6.8 that has small rifle primers?

Also, the .308 Winchester family of cartridges and any wildcat based on it. I've got a couple hundred rounds of SR primer Remington Benchrest cases that I use for "special applications." Indeed, I've even used those cases for full power .358 Winchester loads in older Browning BLRs, using CCI #41 primers. (It's a long story.)

And no, NSP64, SRM and LR are not equivalent. SRM primers are used pretty much exclusively in high pressure cartridges. LR, on the other hand, are formulated to light the fire in low pressure rounds and medium/high pressure rounds. Not to mention the differences in brand.

Any particular reason why you're being so cagey about the specifics of the situation? Without that knowledge, our input is based purely on speculation and essentially useless.

[mike in co]

Also, the .308 Winchester family of cartridges and any wildcat based on it. I've got a couple hundred rounds of SR primer Remington Benchrest cases that I use for "special applications." Indeed, I've even used those cases for full power .358 Winchester loads in older Browning BLRs, using CCI #41 primers. (It's a long story.)

And no, NSP64, SRM and LR are not equivalent. SRM primers are used pretty much exclusively in high pressure cartridges. LR, on the other hand, are formulated to light the fire in low pressure rounds and medium/high pressure rounds. Not to mention the differences in brand.

Any particular reason why you're being so cagey about the specifics of the situation? Without that knowledge, our input is based purely on speculation and essentially useless.

i did say common......i too have rem br brass....so not ANY 308.....only special case cases.........

[dale2242]

Try Remington 7 1/2 primers in your cases with small primer pockets.. I used them in 7 BR brass with 4895. The 7 1/2 is a "hot" primer....dale

[Ricochet]

May be a bit off topic, but the CCI #34 primers packaged for arsenal use say that they're for loading .30-06, 7.62 NATO and 7.62x39. They're magnum strength large rifle primers!

[BD]

Also .450 Bushmaster. Bushmaster's factory brass uses small rifle primers. Brass made by cutting down .284 cases of course use large rifle primers. +1 on the Rem 7 1/2s for a srp in a larger case.
BD

[HORNET]

NSP64, You'd need to try it for your specific circumstances. IIRC, back when the .22 Cheetah (.22/.308) was popular, there were frequent reports of loads going bad quickly with SR primers and ball powders when the weather got cool. That and the Military's use of the LR primer in the 6.8 SPC, make me think that ignition can readily get erratic with SR in the cold.

[NSP64]

It is a 30 bellm. I have some 'factory' loads with LR primers that were made using 444 brass. Then I made some SR primered cases from 7mm BR cases. The same load in the cases give totally different performance. Were talking 27 gr Reloader 7 (slight compression) under a 125gr full condom pill. I was thinking of making some from .308 cases.

[S.R.Custom]

It is a 30 bellm. I have some 'factory' loads with LR primers that were made using 444 brass. Then I made some SR primered cases from 7mm BR cases. The same load in the cases give totally different performance.

In what way? Slower? Bad accuracy? In any event, that's too much powder for a simple small rifle primer like the Rem 6 1/2.

Personally, I'd form up a few cases using the various parents, .444, 7BR, etc. And then I'd weigh them to find the one with the greatest powder capacity, and go with that. If that's a LR primed case, you're good. If that ends up being a SR primed case, it's not the end of the world. Use a SRM primer, or a CCI #41.

Before you make a bunch of cases from the .308, section one and compare it to the others. I've not done the .30 Bellm so I can't say for certain, but I've fooled with the .308 family a bunch, and it's my guess that the .308 case may be the worst one of the bunch for powder capacity.

[StarMetal]

joe,

ohh, i was talking about COMMON rounds.......(lol....ducking)

yes 6.5 has a following, but isn't the 6.8 running away from it ?( that is a question, not a statement). i do sell stags, and have sold two of the 6.8's in the last couple of months.


mike in co

I don't know about the 6.8 running away from the 6.5 Grendel Mike. It appeared it was when Remington was selling it, but they kind of dumped the guns for it. I'm not even sure they still have the ammo. Silver State makes lots of ammo for it. The Grendel on the other hand keep gaining momentum. The problem with the Grendel is AA's stupid contract to be able to make guns for the round.

Joe

[S.R.Custom]

Eh, they're both wriggling on the ground in slow, agonizing death throes like a bug hit with not quite enough spray. A shame, too, because the faster the both of them disappear into the mists of history, the sooner the world will realize that the future lies in the 7mm TCU... :-P

[HORNET]

I think they're both victims of the same kind of marketing genius that made the Remington BR rounds such overwhelming commercial successes..