Win 748-magnum primers?

[disco stu]

Hey all. I've found 1.5kg of Winchester 748 at a price I can't refuse, so I've figured I'll use this to kick me off reloading the 308 and use it till it runs out.

I'm reading a bit about using magnum primers with ball powder in general (Nick Harvey), and with Win748 in particular (forums, plus speer manual lists it used with 150gn and 748 for 308w). In other places I'm seeing advice not to use magnum primers at all if not needed.

Any opinions here-buy the magnum primers, get normal large rifle, or go with a particular brand because it works well with w748?

Thanks in advance

Stu

[Oldbloke]

Lol

http://forums.accuratereloading.com/eve ... /635109286

[Oldbloke]

Sometimes the answer is staring you in the face. This is out of my old pdf Winchester loading manual.

Resized_Screenshot_20211031-180714_Drive.jpeg (249.31 KiB) Viewed 3157 times

[disco stu]

Thanks Old Bloke, again! I really need to read that manual more thoroughly

While I'm sure this one isn't really a big issue, I'm intrigued by the different information given out by respected people/companies

[Larry]

Dont use magnum primers they wont help with more accurate loads. There are heaps of people that do recommend using them it doesn't make it the right thing to do. It is not a good way to beef up a load.

[disco stu]

From what people have said it's apparently harder to ignite. I'm wondering if the idea for it comes from people in the US and Canada shooting in temperatures that are colder than we can turn our freezers down to, or something like that.

It's not like many people would say Nick Harvey is someone to argue with, but that it makes him right though.

The link OB linked to mentioned that people think because case is full that it's harder to ignite. I actually thought the opposite would happen, that it would ignite easier and more evenly with full case. Separate question though

[bladeracer]

I only use magnum large rifle primers, I don't bother buying any standard ones, so all my LR cartridges use magnum primers. I have tested them in groups with standard primers mixed up and have seen no measurable differences between them.

[wanneroo]

I generally use CCI #34 mil spec primers which some say is more like a magnum primer.

I have loaded Win 748 in 308/7.62 NATO, no problems I can recall but I think some have mentioned it's sensitivity to temp changes. I use IMR 4895 mostly for 308.

I still have a pound of it on my shelf, actually reminds me I haven't loaded any 308 for a while, it might be 4-5 years since I loaded any. A lot of it due to buying thousands of rounds of surplus Hirtenberger Austrian stuff, I'll be shooting that for a while.

As I recall the loads I did with Win 748 was 147g FMJ and 150g FMJ.

[disco stu]

Thanks guys.

Waneroo-is that temp sensitivity gong to be less of an issue here seeing we get nowhere near as cold as you, and range from lowest winter to hottest summer temp is nowhere near as large? I also figured I wouldn't be loading up to as hot as I can, so I hope it's not a problem in that way when shooting in summer

I got some 4895 (2206h) also from the same guy. Only 500 grams though so I'll use that for reduced loads I want to play with, and the 1.5kg of 748 for full power loads

[Larry]

ADI powder is very temperature tolerant I doubt you would have any issue with it. esp 2206H I shoot that comp in 308 from the coldest in winter to the hottest in summer and while I keep the ammo out of the sun and do my best to limit any extremes it is very consistent and I dont have to make any allowances.

[bladeracer]

Thanks guys.

Waneroo-is that temp sensitivity gong to be less of an issue here seeing we get nowhere near as cold as you, and range from lowest winter to hottest summer temp is nowhere near as large? I also figured I wouldn't be loading up to as hot as I can, so I hope it's not a problem in that way when shooting in summer

I got some 4895 (2206h) also from the same guy. Only 500 grams though so I'll use that for reduced loads I want to play with, and the 1.5kg of 748 for full power loads

I would've thought we would have some of the more extremes of weather than a lot of places. Even Perth would see below zero overnight to 45+ during summer.

I was responding to a guy years ago in the north of the US that was trying to make a cool air intake system for a bike to reduce the air temp by maybe 10F and wanting to know how much more power it would make. I suggested he go for a lunchtime ride and compare whether he could feel any less power than when he rode to work that morning

[disco stu]

Ha ha!

There may be places in Australia that have a fair degree of temp variation, but I still think we would be hard pushed to match northern usa and Canada between winter and summer temps.

We stayed at Bracebridge in Canada with in laws, and their previous winter it was -40c. Temp while we were there in summer was about 30c, like our typical summer temp here. I gather they can get a bit higher in summer, maybe 5-10. So temp swing in bracebridge about 75C +, temp swing in places I go is about 40-45c.

I was shocked about the temps they see. I always assumed when younger that everywhere had a similar temp change range, so if they go to negative 20 their maximum would be about +25.

[bladeracer]

Ha ha!

There may be places in Australia that have a fair degree of temp variation, but I still think we would be hard pushed to match northern usa and Canada between winter and summer temps.

We stayed at Bracebridge in Canada with in laws, and their previous winter it was -40c. Temp while we were there in summer was about 30c, like our typical summer temp here. I gather they can get a bit higher in summer, maybe 5-10. So temp swing in bracebridge about 75C +, temp swing in places I go is about 40-45c.

I was shocked about the temps they see. I always assumed when younger that everywhere had a similar temp change range, so if they go to negative 20 their maximum would be about +25.

Do they get similar variance during a day as us, like 20C between overnight low and daytime high?

[disco stu]

I'm guessing probably not there, but not certain.

My original comment was winter to summer for temperature effects with that powder, as in you develop your load when it's like -30 or something stupid, and then shoot it in summer at +20 with rounds sitting in the sun. I see now you're saying variation between sunrise and midday or similar.

[bladeracer]

I'm guessing probably not there, but not certain.

My original comment was winter to summer for temperature effects with that powder, as in you develop your load when it's like -30 or something stupid, and then shoot it in summer at +20 with rounds sitting in the sun. I see now you're saying variation between sunrise and midday or similar.

I struggle to believe ambient temperature can have any measurable effect compared to the thousands of degrees occurring during combustion.

I suppose I should load some ammo that is pushing pressure signs when fired on a -5C winter's morning, then wait and fire them in the heat of a summer afternoon when it's 60C, and see it makes any difference. I doubt it would. The powder might have trouble igniting the same at both extremes, but I doubt there'd be any significant increase in pressures.

[wanneroo]

Thanks guys.

Waneroo-is that temp sensitivity gong to be less of an issue here seeing we get nowhere near as cold as you, and range from lowest winter to hottest summer temp is nowhere near as large? I also figured I wouldn't be loading up to as hot as I can, so I hope it's not a problem in that way when shooting in summer

I got some 4895 (2206h) also from the same guy. Only 500 grams though so I'll use that for reduced loads I want to play with, and the 1.5kg of 748 for full power loads

I'm sure you wouldn't have the temp variations I would. On very rare occasions at night in winter it can go as low as -30 and in summer it can hit 40C on rare heat waves. But I probably wouldn't be shooting in those extremes. The days I would shoot in winter would probably be about 0-5C during the day and in summer I probably would not be out doing any shooting beyond the low 30s.

I was aware of the supposed temp sensitivity of Win 748 but wasn't overly stressed about it. As recall the loads I did with it were plinking loads for out to 100 meters, so I think I was 2-3 grains off max loads. No need to waste extra powder when I'm not going the distance.

I got an unopened can of it so I probably need to figure out what load to do with it.

The US Military used Win 748 for decades in 5.56x45 and also as I understand 7.62 NATO, so if it was good enough for them, it should be good to go. For all I know it might still be used.

[disco stu]

The US Military used Win 748 for decades in 5.56x45 and also as I understand 7.62 NATO, so if it was good enough for them, it should be good to go. For all I know it might still be used.

I thought I read that it was used by military. They're generally picky about that sort of thing, and would have less ability to control temperature when in the field I imagine. Sounds like another internet myth

I struggle to believe ambient temperature can have any measurable effect compared to the thousands of degrees occurring during combustion.

Yeah, I think similar to that as it's a miniscule difference % wise, but figure I'm not qualified to say anything either way on it

[Oldbloke]

The US Military used Win 748 for decades in 5.56x45 and also as I understand 7.62 NATO, so if it was good enough for them, it should be good to go. For all I know it might still be used.

I thought I read that it was used by military. They're generally picky about that sort of thing, and would have less ability to control temperature when in the field I imagine. Sounds like another internet myth

I struggle to believe ambient temperature can have any measurable effect compared to the thousands of degrees occurring during combustion.

Yeah, I think similar to that as it's a miniscule difference % wise, but figure I'm not qualified to say anything either way on it

That is accurate. I would not be surprised if ADF spent perhaps 4 years talking to specialists and conducting very though testing before changing anything related to rifle ammo manufacturing.
The development of their smoke flares took about 3 or 4 years from memory.

[disco stu]

Not to mention, if it was that big an issue I figure there would be warnings everywhere about it and people wouldn't use it any more.

Does this mean that winchester 748 is the tacticool powder?

[Oldbloke]

Not to mention, if it was that big an issue I figure there would be warnings everywhere about it and people wouldn't use it any more.

Does this mean that winchester 748 is the tacticool powder?

Or warnings in the manual, or withdrawn from sale.
The explosives industry is very conservative. Would never leave the factory if it was an issue.