Position sensitive powders

[flydoc]

I have a question about position-sensitive powders , specifically whether magnum primers ameliorate the need for dacron or pre-shot tipping in rifles. Any experience or thoughts? Did I miss any threads on this?

[Wayne S]

IMHO, no, in fact a magnum primers may exacerbate the situation, My experience is based on only one situation so take it for what you will, while trying to find a low recoiling load in a 30-30 chambered 10" Contender, well to make a long story short I was trying Unique with LRP & LPP, positioning and not positioning the powder, in both cases the LPP gave single digit ES & SD, while the LRP gave ES& SD in the 20's & 30's

[runfiverun]

quite often I find better accuracy with a colder primer I do however need to add more powder to the load to gain back my velocity.
the higher powder amount [usually a grain] can quite often fix the variations you see from position.

even powders with a reputation for not being position sensitive [unique] will be sensitive if you lower the volume too far. [like below 8 grs in some cases]
blowing it around in the case with a strong primer blast won't help the situation.
a positioner will help, so will changing to a fluffier powder that is close in burn rate..
like going from unique to 800-x or steel.

[jcren]

Again, only one instance, but a super light unique load in 38 spl was unreliable and even occasionally squibbed with standard primers, but with magnums they are my go to for quiet or recoil sensitive loads.

[flydoc]

I appreciate your input. I didn't know if there was a " rule of thumb" that applied or not. I wondered if the magnum primers blew out the powder or ignited it better.

[runfiverun]

there is a lot of combinations that work and some that don't.
in my D.W. 357 mag, the short little 358091 wad cutter over 6 grs of unique and a sp mag primer is super accurate, even more accurate than the 358477 at target speeds with clay's, red-dot, 231, titegroup, and maybe even bulls-eye [I haven't tried it just yet]
6 grs of unique isn't a light for the case amount and fills up the airspace well.

[madsenshooter]

No rule of thumb I know of, another one of those, it depends. I've used magnums with Blue Dot and they worked fine. Accuracy and consistency were better with them. But I compared primers with a surplus powder that burns around blue dot speed and got bigger groups with the magnums vs regular. Then there's these unleaded Tula primers I bought. They don't seem to light anything consistently. Waiting for the 4th of July so I can set off the remaining 4900 in bulk! How big a jar does it take to hold 4900 primers?

[runfiverun]

mason jar should do it.

[walltube]

flydoc,
You do not specify what caliber, or type, cartridge you are wanting advise for. If your inquiry is a general question, my .02 cents worth.


300 Winchester Magnum: 17.5 grains Unique sparked by standard large rifle primers. In a large capacity case such as 300 WM it is necessary to keep the Unique gently snugged against the flash hole for best performance. What works best for me is one single sheet of butt wipe paper cut into four equal quarters. A one quarter square is gently tamped into the case with the eraser end of a pencil. Poly fill did not render as uniform results down range as the paper. No, I do not know why. Cannot possibly be my fault.
The projectile is an ancient Lyman-Ideal 308-311 @ 210 gr. making holes in paper 50 yds. distant.

In closing there is economy of components, low recoil-muzzle blast and confetti to celebrate each pull of the trigger. FYI: Ranges in my neck of the woods will ban a shooter for all eternity if they attempt to raise the muzzle. Bad ju-ju.

Hoped to have been of some help, good luck & good shooting.....
Wt.

[flydoc]

Thanks Walltube and everybody. My question was a general one, not caliber-specific. I have a range at home that has a gentle downslope, so position-sensitive powders are an issue for me. I find that I am better off with 2400 or the like , instead of unique , as my target is not level with the bench. Even when I tip the muzzle up prior to the shot, I have to aim a little downhill, and that results in less than ideal ignition without some sort of filler. Have plenty of unique, but reserve it for pistol due to that factor. Will continue to use TP or dacron with the unique in my rifle loadings .

[BAGTIC]

I use Walltube's method when fire forming new cases. I believe the main thing is to keep the powder close to the primer. Another factor is the charge density. Very bulky powders such as Red Dot fill more of the case so the powder is less apt to shift position away from the primer.

[35remington]

Given that the powder near the front of the case cannot move the same way as powder near the back, and also given that the powder so located "shields" the powder behind it from ignition, hotter primers don't help reduce velocity variations from powder positioning.

Said by a guy who's extensively tested for just that in a number of cartridges.

[HARRYMPOPE]

No set in stone rules. I’ve seen it work manyh ways. With or without filler and magnum or standard primers. The military guns they are used are often not accurate enough to tell the small difference.This is based on results at many head to head cast bullet military matches attended BTW.

[MikeBitzenburger]

I find the opposite results with 2400 VS Unique in 308-8X57-30/06 class cartridges anyway. The unique shows less position sensitivity and has thus far ALWAYS been more accurate than the 2400 at the same reduced speeds in my guns. I and my rifles actually prefer Green Dot for such loads but I have so much unique to burn up I use it instead of buying the green dot I much prefer.