120SMK and IMR 8208

[Fredman]

I've looked all over looking for a max load for these. I've tried 27.3 to 28g. With no issues. Is 28g max? I see the 123g SMK max charge is 28.5.

Thanks,

Terry

[NugginFutz]

Much higher than 28.5 and you're in a rough neighborhood, when dealing with 120's and above. Most people who've been there report pressure signs beyond.

I recall someone mentioning, also, that 8208XBR is like a bipolar girlfriend... Things are ok. Things are ok. WHAT DID I SAY??!!

If you have a chronograph available, I'd be very watchful for departures from the velocity curve as you're approaching 28.0 and beyond.

[Fredman]

Ok. Thanks for the advice. I do have a chrono. It does have a couple of war wounds...

[LR1955]

FM:

I have shot a lot of 120 SMKs with 8208. Do not exceed 28 grains of 8208 and when using 28 grains of 8208, use brass with a small primer.'

It doesn't shoot the 120's better than other powders that are a bit slower and more suited to that bullet weight. 2520 is a good powder for the 120 range bullets.

LR1955

[lwminton]

FM:

I have shot a lot of 120 SMKs with 8208. Do not exceed 28 grains of 8208 and when using 28 grains of 8208, use brass with a small primer.'

It doesn't shoot the 120's better than other powders that are a bit slower and more suited to that bullet weight. 2520 is a good powder for the 120 range bullets.

LR1955

Does that apply for the 120 Scenar L bullet?

[LRRPF52]

Yes, AA2520 is a good powder for the 120gr Scenar-L, and any of the other 120-123gr cup and core bullets. I would personally recommend CFE223 for this class of bullets though, based off of what I and others have experienced with it. It seems to be the ideal powder for the 6.5 Grendel with 120-123gr cup and core pills.

[lwminton]

so 8208 is your third choice for Scenars? I ask because I am going to start loading soon for a new Grendel and am having trouble finding 2520 but can get CFE. Also, should I forget about 4895 and RE 15 which I used for the 6mm AR.

[LR1955]

LW:

I didn't mention CFE223 because I haven't used it but I would trust LRRP52 if he says it is a better choice than 2520. Enough guys here have used CFE with the 120 grain bullet range that I would buy some if I didn't have a bunch of 2520.

8208 is a bit fast in Grendel terms for 120's. Not as efficient as CFE or 2520 is probably a better term.

4895 and RL15 do not have the bulk density to give you decent velocities with a Grendel. They are safe to use but are not even as efficient as 8208. I use H 4895 and Varget in my 6 AR to great effect but you won't find them to be efficient with the 6.5. Big difference in how pressures are built up between the two. Thats why you find mostly ball powders to be the powders of choice for the Grendel.

LR55

[lwminton]

Ballistics is a complicated science. I have shot 105 gr Berger bullets (match and VLD) in the 6mm using RE 15 and 4895 in the Hathcock Match at Cherry Ridge in NJ and am surprised to hear that another 13 grains makes that much difference in the same case.
I once bought a book on ballistics and was left scratchin' my head then too! Thanks for all the advice. I will start with CFE and then try to find the 2520. I joined the data base too and will follow along there but saw there were no loads for the Scenar L yet.

[LRRPF52]

Scenar-L is a new product line from Lapua, so it will take time, but I would approach it like a 120gr Berger or any of the cup and core 120gr target pills really for charge weights, but figuring out ogive length and COL based on your chamber.

I just compared the 3 120gr 6.5mm target bullets, namely the 120gr SMK, the 120gr Berger, and the 120gr Scenar-L, and the Scenar-L has the longest OAL, and longest boat tail, with an ogive that looks more like the 120gr Berger than the SMK. Stated G1 BC is .497 and G7 is .246 from Lapua.

[lwminton]

My Grendel is an AR (Precision Firearms) and I was hoping to be able to load them magazine length. Is that in the cards? The Hathcock Match is single load so I can load them long (even touching) and forget the magazine. Is there a particular bullet that would work best mag length?

[waveslayer]

Fredman, pm me. I have some awesome loads with the 120 SMK using 8208 and CFE. If you are interested

[LRRPF52]

My Grendel is an AR (Precision Firearms) and I was hoping to be able to load them magazine length. Is that in the cards? The Hathcock Match is single load so I can load them long (even touching) and forget the magazine. Is there a particular bullet that would work best mag length?

Precision Firearms has a factory 120gr Scenar-L that I've been shooting since SHOT Show. I grabbed 2 bags of them, 100 round each. They are loaded to 2.260" COL in PPU brass, the ones I have.

[bwaites]

123 grains is pushing 8208 to the max, and the stubby, longer bearing surface of the Sierra 120 would make me think that 28-28.5 grains would be max load.

8208 is an awesome powder, one of my favorites, but it is a bit two faced. It does not seem to build pressure evenly in the small Grendel case, with it going from good, good, great, great, great, then BOOM! It is awesome under 107 Sierras at 28.5 grains, and under 108 Scenars at the same, and you could load it a bit hotter, but that is the accuracy node for me. I've seen it described as a Bipolar Sports Illustrated model girlfriend! Everything is better than awesome, and then its not!

CFE seems to really be in a sweet spot for the Grendel, AND it helps keep the barrel clean!

TAC also is a great powder, and I think it is a bit more forgiving for the Grendel than 2520, but finding it has become impossible.

[Fredman]

Thanks all. I will try the CFE. Bwaites, I also tried the 108s with 8208. I only had a few left, so I worked my load up testing with three shot groups. Four groups all measured .3-.5" at 100yds. Guess I need to buy more.