reloading with ppu brass

[usar_ds]

ok so i am reloading once fired wolf mpt brass

I am using win-large mag rifle primers, aa2495, and nosler 120gr bt

OACL 2.245 (nosler recommended), with a light to medium taper crimp

i contacted accurate powder and they gave me ramshot TAC data and told me to use it as a guideline, min charge 25.8 max at 28.7.

but this data of course calls for win-small rifle primers

i know that I need to load lighter for the large mag rifle primers but how much lighter?

i have been laddering up from the starting load and I am at 27.0gr for my next string

would 28gr. be safe to eventually work up too, or is that too high?

any help would be appreciated

[bwaites]

ok so i am reloading once fired wolf mpt brass

I am using win-large mag rifle primers, aa2495, and nosler 120gr bt

OACL 2.245 (nosler recommended), with a light to medium taper crimp

i contacted accurate powder and they gave me ramshot TAC data and told me to use it as a guideline, min charge 25.8 max at 28.7.

but this data of course calls for win-small rifle primers

i know that I need to load lighter for the large mag rifle primers but how much lighter?

i have been laddering up from the starting load and I am at 27.0gr for my next string

would 28gr. be safe to eventually work up too, or is that too high?

any help would be appreciated

In general, my large primer loads are 1/2-1 grain smaller than my small primer loads. You should be safe up to 28, but work up by .3 grain jumps, no larger, and closely monitor your chronograph. A big jump in velocity that is not linear with the previous jumps means pressure just jumped A LOT!

[usar_ds]

Thanks. I have definitely been jumping a little too much per incrament (.4 or.5) then. I will definitely not go above .3 then. I appreciate the help been having a hell of a time learning to reload grendel correctly.

[rasp65]

usar PM me me I will email you a copy of some data in an Excell file that AA used to have on their website for PPU brass. The data uses lg rifle primers not magnum primers. The volume of powder in the Grendel does not require magnum primers.

[usar_ds]

Now I was under the impression you should use mag primers to reduce the risk of slamfires. Am I gonna have to pull the bullets on this latest string? To start over with reg large primers?

[bwaites]

Now I was under the impression you should use mag primers to reduce the risk of slamfires. Am I gonna have to pull the bullets on this latest string? To start over with reg large primers?

Mag primers do tend to have a thicker cup and their use in AR's (or regular primers with a thicker cup) is advised. You don't need the extra flame necessarily, but you need the thicker cup.

[usar_ds]

Mag primers do tend to have a thicker cup and their use in AR's (or regular primers with a thicker cup) is advised. You don't need the extra flame necessarily, but you need the thicker cup.

That's what I thought. Glad for the clarifacation

[rasp65]

According to this article the cup thickness between mag and regular large rifle primers is the same: http://bulletin.accurateshooter.com/...james-calhoon/

[NugginFutz]

Actually, I don't see that article supporting that position, at all. It varies between manufacturers. CCI magnum and BR primers have thicker cups than their standard primers. Likewise with Remington and Federal (at least with respect to their match/BR primers.) Winchester seems to be the only manufacturer in that table with cup thicknesses that don't vary across their offerings.

Of those listed, CCI and Remington seem to have the thickest primers, in either SR or LR offerings. This is not to mention the CCI #34 or #41 primers, which are purpose built to have even thicker cups to mitigate slam fires.

[bwaites]

Large rifle primers seem to have the same cup thickness is rasp65's point, I think. I was unaware of that, believing that small and large rifle followed the same pattern.

I was referring to the reasoning for using magnums in small rifle primers, but my post above certainly didn't specify that, so I'm glad he found the article and posted it! Good information to know.

[koden]

From the article:

It would be nice to list this info. It seems like a very important data point that is missing in his evaluation.

If all LR primers are the same thickness but some are harder than other then it seems logical that the harder cups will be better for higher pressures.

[bwaites]

From the article:



It would be nice to list this info. It seems like a very important data point that is missing in his evaluation.

If all LR primers are the same thickness but some are harder than other then it seems logical that the harder cups will be better for higher pressures.

Very true, but getting them to release that info will be a dream. In the Grendel, with its 50-52000 PSI limit, its no issue, though, any of the large rifle primers are fine, so long as you keep a realistic powder load.

[koden]

We would not need the specific hardness. We just need someone to load up 3-5 of each primer with the same components and see which ones dimple more/less than others.

I might have to try that in my LR-308.

[bwaites]

We would not need the specific hardness. We just need someone to load up 3-5 of each primer with the same components and see which ones dimple more/less than others.

I might have to try that in my LR-308.

Doing that would be more consistent with no variables, ie:

Clean brass, size brass, place primer, load into bolt action rifle, chamber cartridge, fire. No powder, no bullet, no pressure. Just the firing pin strike.

BUT.... I'm betting you there is 1-2/10,000 difference between primers, probably unmeasurable without REALLY good tools, like optical comparators.

[NugginFutz]

Large rifle primers seem to have the same cup thickness is rasp65's point, I think. I was unaware of that, believing that small and large rifle followed the same pattern.

I was referring to the reasoning for using magnums in small rifle primers, but my post above certainly didn't specify that, so I'm glad he found the article and posted it! Good information to know.

>sigh<. Once again, I get burned for reading an article with an eye to how it pertains to my own needs. I stand corrected. Good find, rasp65

ETA: I did find this, though. It may demonstrate some very large differences between primer choices, based on their flash energy. Cool photos, in any case.

http://www.6mmbr.com/PrimerPix.html