Next up............6.5 WSM!

[scope eye]

I don't even use mag primers in my RUMs.

Dean

[Hotolds442]

That's because they're not Magnums, they're ignited from Mission Control silly.

[fgw_in_fla]

That's because they're not Magnums, they're ignited from Mission Control silly.

Don't encourage him.

You don't use magnum primers?
I've been meaning to ask you about that but since you brought it up (actually, you reminded me. I forgot) - Even with very fine powders?

[scope eye]

I didn't come here to be made sport of, I usually go somewhere else for that,LOL
As far as primers I find using regular primers make slow powders burn slower, and helps to avoid bridging which is what causes pressure signs and pressure spikes. which really helps when you are burning wholesale amounts of powder though, a small caliber it was never intended to.

Powder Bridging is like when you are filling the case with powder and have to tap the funnel for it to flow down into the case Powder Bridging is basically the same thing but in the opposite direction under alot more pressure!!

Basically, when X amount of powder is trying to pass through a certain diameter hole, it has a limit in how fast the powder can flow through this opening.

With a very large case capacity round with a modern, sharp shoulder angle, this becomes a problem with smaller caliber cases. Now this depends on the caliber as well as the diameter of the case powder column and the total powder volume.

What happens is when a round is ignited by the primer, the blast from the primer forces the powder in the case foward until it is stopped by the shoulder and seated bullet. Then it begins to ignite.

As the pressure inside the case increases from the rear of the case forward, it increases the pressure on the powder. Powder bridging occurs when the pressure actually locks the powder granuals together because they simply can not pass though the neck of the case and pressure increases dramatically.

Dean

[fgw_in_fla]

I'll keep all of that in mind when I work up loads to "X" amount.

I was just curious since I'm using the info for a fact finding mission I've tasked myself with. Since adding a 300 Win Mag to the arsenal, I didn't want to add another type of primer.
Mr. Lyman says - We used WLR for our load testing.
Mr. Speer shows magnum primers.
3 guys at the local reload supply store - Won't work without using magnum primers.
The RSO at the range - whatever.
Dean - A lengthy overly technical explanation on why he's too cheap to buy the right kind of primer.

SOoooooooo....
I guess I'll go with Deano's recommendation. He hasn't let me down (yet) and I haven't blown up any of my hardware (yet) using his advice.
Thanks for your input.
Have a nice day.

Uncle Frank

[scooterf79]

Deano is getting roasted today... 😉. Seriously though, it makes sense, guess I had never thought of it that way. I may need to look into that on some of my bigger cases too.
Scooter

[yobuck]

Im not buying in on your theory Dean.
I think certain powders need magnum primers. Or just a tiny pinch of bulseye to get the fire lit. lol

[scope eye]

A lot of folks may not know this, but Mag Primers were originally designed for sub zero warfare.
I learned it for myself through experience, and only to be reinforced by Kirby Allen of Allen Magnum Fame.

Hey Fiftydriver, what exactly is powder bridging? I have noticed you mentioned it a few times. The only info I could find was about the powder getting stuck when it is poured into the case. And that doesnt sound like it.

Powder Bridging is basically the same thing you discribed but in the opposite direction under alot more pressure!!

Basically, when X amount of powder is trying to pass through a certain diameter hole, it has a limit in how fast the powder can flow through this opening.

With a very large case capacity round with a modern, sharp shoulder angle, this becomes a problem with smaller caliber cases. Now this depends on the caliber as well as the diameter of the case powder column and the total powder volume.

What happens is when a round is ignited by the primer, the blast from the primer forces the powder in the case foward until it is stopped by the shoulder and seated bullet. Then it begins to ignite.

As the pressure inside the case increases from the rear of the case forward, it increases the pressure on the powder. Powder bridging occurs when the pressure actually locks the powder granuals together because they simply can not pass though the neck of the case and pressure increases dramatically.

In the case of my Allen Mags, the 257 and 6.5mm are the only two that so far have had this problem. The simple cure is to use Ball powder. This solves the problem simply because this powder shape can flow at MUCH higher rates through even smaller neck diameters then any stick powder.

In the 270 and larger Allen Magnums, this has not been a problem at all but I still generally use the real slow burning ball powders simply because of their lower burn temps and they are much easier on the throat of the chamber as the powder is forced through.

Hope this helps some.

Kirby Allen(50) __________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com (http://www.apsrifles.com)

allenmagnum@gmail.com

Dean
(allenmagnum@gmail.com)

[fgw_in_fla]

Im not buying in on your theory Dean.
I think certain powders need magnum primers. Or just a tiny pinch of bulseye to get the fire lit. lol

Now your talkin'...

Except I use Win 231 since I have more of it.

Excellent tech info Dean.
I take back most of what I was saying about you the other day.


Edit - Never mind. I was just looking at here - www.apsrifles.com - the website you put up. I always thought you had a screw loose with some of the loads & cartridges you come up with. Now I know why...

[Hotolds442]

Ventured up the hill yesterday, only to find myself in the clouds. Visibility was 150 yards. No long range shooting happening in those conditions. I'm gonna try and run up this morning before work and see if I can get some shooting in.

[scooterf79]

Guess thats the pacific Northwest for ya lol....im gonna try to hit the range after work in the morning....its blistering hot(for this time of year ) here this week so, no shooting in the afternoon here, just too hot.
Scooter

[psharon97]

I tried using standard CCI large rifle primers in my 7mm rem mag. I was getting hangfires on almost every round. I switched to Winchester LRM primers and fixed the problem. I would stick to standard primers if at all possible, and only go to magnum primers if you're having problems.