AA 2460 and 'magnum' primers - any experience?

B

BobCat45

New member
Speer #12 calls for magnum primers for AA2460 in .223 Remington. Book shows good velocities and loads for all bullet weights they list except 50 grain.

The manufacturer's website https://accuratepowder.com/load-data/ load manual does not mention 'magnum' primers for this powder.

H335 is the only ball rifle powder I've ever used and it did not seem 'hard to ignite' but that was years ago so my memory may be bad.

I use CCI BR4 primers for Midrange prone - as long as I still have them. I have no 'magnum' primers.

The backstory is that I've been using AA 4064 that I lucked into, after using up an old 8 lb can of IMR 4064 that I also lucked into. Then I found AA 2460 in stock and ordered it, while looking for more 4064.

White Oak had a reloading page years ago and I found it in the Internet Archive - https://web.archive.org/web/20160227230641/https://whiteoakprecision.com/info-reloading.htm Speaks well of AA 2460 so I at least knew that in 2016 people who shoot much better than I do liked it a lot in .223.

It also is supposed to meter well, being a ball powder. IMR 4064 does not - needs to be trickled. AA 4064 meters better but still needs to be trickled. Once the cases are all prepped and primed, it still takes me 1-1/2 - 2 hours to trickle and bullet seat 100 rounds, so throwing charges using my Uniflo is attractive, if it is precise.

So - anything anyone wants to tell me about AA2460 would be very welcome.

Thanks!
 
Only experience I have with 2460 is in 6.5 Grendel and 6 ARC in AR platforms. I have always used CCI450s for the thicker cups. I will say that you get good velocity in those cartridges though
 
Thanks hounddawg!

Did you want the thicker cups to lower the chances of a slamfire in an AR-pattern rifle?

I was wondering if the magnum primers were hotter or more energetic, required because the ball powder might be harder to initiate. Odd that Accurate does not mention this. Time for me to re-read their manual.

I suppose the best thing to do is wait until they ship the powder and load some start-level rounds, and see if they shoot.
 
When I first started reloading my mentor said always use a magnum primer for AR's for slam fire prevention. I have no idea if that is a real concern or not but it is always the way I developed the loads so that is what I do.

Another thing I have heard but not experienced yet is that 2460 can be a bit temp sensitive in hot weather. I only started using the stuff last fall so I will be chronoing the loads as summer comes on. My loads are not near max anyway but I may have to retune them for accuracy once we get back to the 90's and 100's
 
Thanks again!

The only slamfire I've ever had was in my Garand, with CMP-surplus LC ball, when I let go of the bolt a little too soon, single loading standing.

I've shot many thousands of rounds through AR-15s since 1993 and always worry about slam fires bur haven't had one. Early on my 'mentor' told me to quit using Winchester primers because they were prone to piercing, so I switched to CCI.

I read the same thing about temperature sensitivity and will be very careful, but here in Houston it is fixin' to get hot and stay that way until October. I load the week before the match so I'll have some idea of the forecast temperature.

Mainly, I'm concerned about reliable ignition, and whether the ball powder really 'needs' a magnum primer to light.

Testing seems like the only way to find out.
 
I've been present for one military ball slamfire at a match. It can happen, even with military-sensitivity spec primers, which are even less sensitive than magnum primers. The magnum cups are generally no thicker in the large rifle format. In small rifle primers, they usually are thicker. The CCI military-sensitivity spec large rifle #34 is identical to their #250 magnum LR primer, except that it uses a different anvil with shorter, wider spread legs to reduce sensitivity further. Their #41 military-sensitivity spec primer for the AR is their CCI 450 magnum SR primer with the addition of the altered geometry anvil to reduce sensitivity further. AFAIK, the Federal GM205MAR is the only military-sensitivity spec primer that achieves the sensitivity reduction by thickening the cup substantially. Otherwise, it is a GM205M match primer and not a magnum primer. So you have a choice in the military-sensitivity spec primers for SR, about whether you want magnum or standard primer performance. At least, you do when there is stock available.

One of the advantages of 4064 is it has lower fps/grain than many other powders in the 30 cal guns. Varget even more so. This characteristic makes these powders less sensitive to exact charge weight errors than those with higher fps/grain in the same platform. 4064 also tends to burn more slowly when the grains are packed closer together, so a charge that comes out a little heavier but with the same volume as another still shoots similarly to the exact charge. The two types of volumetric measures that treat it well are the Lee patented wiper measures (Perfect and Perfect Deluxe) and the JDS QuickMeasure. The latter is guaranteed to throw stick powders within 0.2 grains, and my copy does that, with most being within 0.1 grains with 4064. This matches the precision of the Federal GM308M ammunition I pulled down twenty years ago. It used 43.5 grains of 4064, and the charges had a 0.4-grain span in my sample of 20. If your load is tuned to a velocity flat spot in the charge weight spectrum, that level of precision in powder dispensing is adequate for most match shooting. Only for long-range or benchrest matches would you likely need to think about going the extra mile and weighing them.
 
You must log in or register to reply here.
Back
Top