Which Primer?

[KMart]

I am just getting started loading for the 6XC. I have both the Wolf Large Rifle and the Large Rifle Magnum. Any suggestions/thoughts on which one to go with would be appreciated.

Ken

 

[GermanS1]

Ken, both of those primers are good choices. They are actually the same primer except for a slightly thicker cup on the magnum version. Unlike the small primers, the standard version of the large ones has no problems with blanking, so I wouldn't hesitate to use them; in fact, that's what I use on my 6XC. If you run into excessive flattening at normal pressures, try the magnums but that shouldn't be the case.

The biggest difference in those primers is simply that they are different lots of the compound. Generally speaking, I find that the primer that gives the lowest MV has the best accuracy. Test both to see which gives a lower MV, then do your regular load workup with that one; I'd bet it'll be a winner.

 

[KMart]

Thanks for the help.
Ken

 

[Laurie]

Ken,

I've also found the (Russian) PMC LR (sold as 'Wolf' brand in the USA) a very good primer in a number of mid-sized cartridges and will be using them as first choice in my new 6XC BR Light Gun / F-Class rifle.


German,

The biggest difference in those primers is simply that they are different lots of the compound. Generally speaking, I find that the primer that gives the lowest MV has the best accuracy. Test both to see which gives a lower MV, then do your regular load workup with that one; I'd bet it'll be a winner.

I've just had a good example myself of your rule of thumb in long-range .223 Rem loads using 90gn Bergers, both BT and VLD. Getting velocity ES values down to .308W levels is a hard job in this cartridge and I loaded up 9 batches of same using Viht N550 in three charge weights only varying by 0.1gn and bracketing a load that had proved a sweet spot with the PMC. The sole variation otherwise in the 3 x 5-round batches was that one lot used PMC SR Magnums as in the load work-up process, the other two lots CCI primers, one 450 Magnums, the other BR4 benchrest/Magnum.

I expected the two lots of CCI primers to give very similar results and for them to be apart from the PMC primed cartridges if any variations showed. Not a bit of it! The CCI-450 and PMC primed rounds gave virtually identical results in terms of MVs, spreads and group sizes; the BR4 was noticeably 'hotter' upping both MV and MV spread and opening groups right up, although that may well be due to taking the load out of the 'sweet spot', of course. I'd have to rerun it with slightly lower charge weights for the BR4 batches to reduce the MVs to that of the other two to really compare, but I was struck by the MV spread increase.

Regards,
Laurie,
York, England

PS I've just been advising a fellow with a query on another forum about bullet sorting and trimming/pointing to have a look at a couple of arfticles on your Rifleman's Journal Blogspot:

http://www.usrifleteams.com/lrforum/index.php?showtopic=12975

(If you do use that link to go onto the Palma Teams' Long-Range Shooting Forum have a look at the thread entitled "Will this 223 work at 1,000?" on the External Ballistics section if you're interested in .223R at long range. I stuck the results to date of my new .223 F-TR rifle there on the bottom of page 2. How does a 4.815" 5-round group in a 1,000yd UK BR Association match on the notoriously windy Diggle range in Upland northern England from the 'mouse-gun cartridge' grab you? The chomping and choking noises coming from our side of the Atlantic are the sounds of words being eaten by some long-range shooters who said it would never work at such distances!)