I've been regaling you all with tales of my quest to produce truly match grade ammo for the 30-40 Krag.  To quickly recap:
a.  Match grade collet bushing resizing die with .332" collet (.002" neck tension)
b.  Brass trimmed to uniform length
c.  Primer hole reamed
d.  Necks cleaned inside and brass tumbled
e.  Brass full length resized with no more than .002" runout
f.  Powder charges all weighed to exactly 40 grains of IMR 4350
g.  Hornady 220 grain JRN seated to uniform length with final runout between 0 and .004".  By far the best results achieved to date.

I loaded 50 rounds of test ammo with 5 different primers:
a. Federal Large Rifle
b. Federal Large Rifle Magnum
c. Winchester Large Rifle
d. Winchester Large Rifle Magnum
e. CCI Large Rifle Magnum (250)

The results at 200 yards were startling:
a.  All the Magnum primers shot considerably higher on the target, about 12" higher, than the standard primer loads.
b.  Magnum primer groups were vertically strung as much as 10-12"
c.  Standard primer loads were approximately 3-4" in size and fairly concentric.  Using a 6 o'clock hold and a 300 yard setting the standard primer loads were clustered consistently around the X/10/9 rings.

The recoil of the Magnum primer loads was noticeably stiffer than with standard primers.

Based on the above I've decided to fore go any further testing of Magnum primers in my gun.  They undoubtedly work for those that recommended I try them, but for me they are not the answer.

The next test loads will be 20 each of the Winchester Large Rifle primer, the CCI 200, CCI BR-2 and the Federal GM Match primer.  20 rounds each should give me sufficient data to make a solid choice or two for testing a larger sample.

Although your load is not a hot load remember that magnum primers can boost pressure.  I don't know why you need them with 4350, it is not a hard powder to light and the Krag case is not a big case.  I use magnum primers in my Garand with WIN 748, as there was an occasional noticeable delay with standard primers, but it is a ball powder. I have never had the problem with IMR series powder in any rifle, even in extremely cold weather. The CC! #34 from what I have gleaned from the CMP forum is a magnum power primer, as military ammo is loaded with either ball or extruded powder and it works even in extreme cold with either powder.

Well, that makes pretty good sense to me.  I do know that the CCI #34 is the military standard primer, and it has a slightly thicker primer cup which helps to prevent the slam-fire issue.  That said, I may just switch back to using a standard CCI 200 for my Krag loads.  We'll see....  I have all winter to contemplate this, as I'm out of commission for a few months (surgery to my shoulders).

Ahhhh... Maybe that's it.  The debate on thicker cups arose from discussions about slam fire in Garand Rifles due in part to the floating firing pin slamming against an overly sensitive primer with a thinner cup... as I recall - the discussion was that the Federal primers were the most susceptible to this, and the CCI primers were the safest.  I might have mistaken or miss-quoted this... but that's how I recall it anyway.  Either way, I'll be using the 34s in my Garand loads from here on out.

So maybe I should hold off on dismissing my use of the CCI 250...  I might just stick with it.  To be honest, it has been working for me so far...

Keep at it Keith - your work is good for all of us, and your data will be invaluable!!!

Paul

My 1898's barrel slugs out at .308 and is in relatively good shape too.  Before I got a hold of it, it spent a couple decades in my dad's gun closet and was rarely (if ever) fired.  Before that, it spent 50 years under the bed of the man who brought it home from France, so I imagine that it's not had too much use in the last 90+ years.  Anyway, I think she shoots great!

That said, this spring, I may spend a little time at a 200 yard range and do a little testing of rounds with both the 200s and 250s... and figure out how my Krag responds to both off the bench.  Once I get that sorted out, I'll create my match ammo for the years matches and I should be good to go.  It's important to remember that not all Krags "Like" the same foods... so what works in your Krag may not work so well in mine... or in others.

Still, as I said before, your work will be invaluable for all of us to follow!   

madsenshooter wrote on Sep 17^th, 2015 at 8:15pm:


In my experiment, the Federal 215 magnum primer was the one that gave me the most vertical spread, and printed the highest on the target.  Based on recoil, velocity was increased.  But since I'm using the same powder charge in all my tests, I can't really comment on your loads.

I called Sierra Tech Line today in an attempt to gain some clarity on what my tests revealed.  According to them:
a. I don't need magnum primers.  using them will only increase ES and SD.  The vertical stringing I saw and the printing higher on the target are both signs I'm using "too much primer." 
b. The Federal 215 magnum primer is in fact the worst offender in this regard.  It was designed specifically to ignite Weatherby cartridges and is the only magnum primer that Sierra states should not be exchanged for other primers, but loads with it worked up carefully.  That same caution is not attached to any other brand large rifle magnum primer.

There are a lot of good studies on line comparing different primers to one another.  Two of the best are from Accurate Loading ( (You need to Login to view media files and links)) and Accurate Shooter ( (You need to Login to view media files and links)).