Small rifle primers...how cold is "too cold"?

[Drago6]

I'm new to reloading, 80% done in sourcing equipment/supplies, the topic of the thread is the current fork in the road i've reached

When considering LRP vs SRP for primers in 6.5cm, most of the information I'm finding is essentially saying "LRP are better for cold climates and SRP are better for mild conditions & accuracy"

I live in New England, and am planning on moving even further north (NH), so cold/wet weather is absolutely going to be present. I havent been able to find much definitive information on where the cut off is for "too cold for using SRP"

The primary reason I'm considering the SRP is because if i use CCI 450's, that would mean I would be using the same primer for both 6.5cm and 6.5grendel (the only 2 calibers i really plan on reloading), with the nightmare of sourcing primers for the foreseeable future keeping things as simple as possible is of some importance.

>tldr, can i get away with CCI 450's in cold (sub freezing) weather, or should i suck it up and go LRP?

 

[918v]

It depends on the powder.

 

[camocorvette]

I've no answer for your too cold question. But from a logistics standpoint I would say LRP. Being as they are slightly more plentiful. At least in my AO I have actually seen LRP for sale. SRP is non existent.

 

[TxWelder35]

I’ve been using SRP in my 260 but recently acquired some LRP brass so I have the option of using either size primer. I want to be able to use whatever size primer I happen to be able to get ahold of.

 

[cornhusker86]

If you are using extruded powders, you should be ok.

 

[TxWelder35]

If you are using extruded powders, you should be ok.

Why would extruded powder be better than ball in the cold?

 

[cornhusker86]

Why would extruded powder be better than ball in the cold?

I've had hangfires with the srp brass and ball powder. Tried the same powder with LRP brass and no issues. [ 6.5 Creedmoor ]

.223 never had a problem.

 

[TxWelder35]

I've had hangfires with the srp brass and ball powder. Tried the same powder with LRP brass and no issues. [ 6.5 Creedmoor ]

.223 never had a problem.

Not necessarily questioning if it happens, I’ve heard quite a few times that it does, but the science behind why. What about extruded powder makes it easier to ignite in the cold?

 

[cornhusker86]

Not necessarily questioning if it happens, I’ve heard quite a few times that it does, but the science behind why. What about extruded powder makes it easier to ignite in the cold?

That's a great question. Wish I had a good answer. My post was based on my experiences, not on any expertise.

 

[Drago6]

Thanks for comments guys, the powder will be H4350. I'll grab some SRP brass to try out, worst case if it has problems in the cold i'll know for sure

 

[Juggerxxx]

I live in Colorado and shoot matches in the winter with no issues ever using CCi400. That is with 223 and 6GT with both Varget and H4350.

 

[Doom]

Since you are using a magnum primer I think you should be OK, especially if using an extruded powder.

 

[Missalot]

It also depends on what brass you have on hand. It seems I am always matching primers to brass, not the other way around.

 

[Onewolf42]

I'm starting to collect components for my 'next' rifle. It will be a 6 Creedmoor. I live in central Florida so I don't have to worry about cold weather issues, but I had to decide between LRP and SRP brass and I opted for LRP brass (ADG) simply because I have around 15,000 LRP but only 3000 SRP at this point.

 

[sinister]

Technically speaking you probably want large rifle primers for extreme cold. Do a web search for EPVAT testing.

There's a reason the Soviets use old-school large corrosive primers to set off their rifle charges (specifically 7.62 x 54R and 7.62 x 39) and seal their ammo in spam cans. It has an incredible shelf life and it lights off when in Russian/Siberian cold.

 

[eja12a]

Not necessarily questioning if it happens, I’ve heard quite a few times that it does, but the science behind why. What about extruded powder makes it easier to ignite in the cold?

According to McPherson in his book " Metallic Cartridge Handloading" ball powders tend to have more deterrents, or various additives, which themselves slow combustion, which makes slow combustion issues even worse at cold temperatures. Also, some extruded powders (like Hodgdon) use higher quality ingredients and a more complex manufacturing process to introduce microfracture into the granule, increasing surface area which helps increase the rate of reaction of combustion (pg 138).

I'm new to reloading and am reading that book. Literally, just read that section last night haha.

 

[918v]

No issues with H4350 and small primers in the cold.

 

[fdkay]

Thanks for comments guys, the powder will be H4350. I'll grab some SRP brass to try out, worst case if it has problems in the cold i'll know for sure

If you get starline brass, they have SRP but with a standard flash hole.
It seems some of the cold weather issues were remedied with the larger flash hole (or so they say) might be because they don't have to swap out the punch.
I've got some .308 match SRP brass that I neck down for my 7-08. Seems to work very well, but it never gets truly cold here.