Need help w/ max powder recommendations for Varget - working up a load

[LR1955]

High initial velocity doesn't mean much at 800yds. My long range load for shooting silhouette at 550yds is the 139 lapua with 27.2 gr of R-15.
That bullet has a BC of .615. It starts out low 2340fps but still has 850 ftlbs at the ram(550yds). This load takes the 35lb ram down. At 800yds
it still clocking 1410 fps and 613ftlbs.

Rich:

You need to tell the guys the rest of the story when it comes to competitive shooters selecting a load and bullet.

Would you rather have a bullet of high theoretical BC and holds two minutes at 800 or a load that uses a significantly (.1 or more) lower BC yet holds one minute at 800? For guys who aren't competitive long range shooters, such a decision making scenario is not uncommon.

May pay for the competitive shooters to describe how they decide on a load for their sport.

LR1955

[LRRPF52]

High initial velocity doesn't mean much at 800yds. My long range load for shooting silhouette at 550yds is the 139 lapua with 27.2 gr of R-15.
That bullet has a BC of .615. It starts out low 2340fps but still has 850 ftlbs at the ram(550yds). This load takes the 35lb ram down. At 800yds
it still clocking 1410 fps and 613ftlbs.

High initial velocity means a lot to me for further long range shooting. Most competitive shooters that are dealing with distances 700-1200m don't mess with any 6.5 loads that are less than 2820 fps, which is barely enough to get 1 MOA spread past 1000m with most rifles. For 550 yards or less, the lower velocities are probably fine. There's no way the 139gr Scenar is a .615 G1 BC either. Lapua's website publishes the theoretical G1 BC value at .578, and the G7 at .290, which is pretty dang good.

They also have radar data on the Scenar line of projectiles with their Quick Target Unlimited ballistics program, so for those of us that shoot at the longer ranges, we can get absolute impact values for drop and wind, versus tinkering with checking out actual results with a theoretical drag model. There won't be any practical difference between the G1, G7, & Doppler track models at 550yds, but the slow initial velocity drops the BC down significantly. Those published BC's are probably more in the realm of 2800-2900fps, since velocity increases BC.

http://www.lapua.com/en/products/reloading

The only 6.5mm bullet they have with a theoretical G1 BC over .6 is the 144 FMJBT, which is listed at .636, and no G7 listed for it.

The 139gr Scenar is one of the most popular 1000yd/1000m bullets used by shooters with 6.5x47 Lapua's, .260 Rem's, and 6.5x284.

[LRRPF52]

Rich:

You need to tell the guys the rest of the story when it comes to competitive shooters selecting a load and bullet.

Would you rather have a bullet of high theoretical BC and holds two minutes at 800 or a load that uses a significantly (.1 or more) lower BC yet holds one minute at 800? For guys who aren't competitive long range shooters, such a decision making scenario is not uncommon.

May pay for the competitive shooters to describe how they decide on a load for their sport.

LR1955

This is the crux of the argument in favor of the Lapua 155gr Scenar over the Sierra 175gr SMK in .308's. You can run the 155 Scenar at over 2820fps, 2900fps+ in bolt guns, and beat the 175 SMK all day long. The 155 Scenar is actually longer and more aerodynamic than the 175 SMK, but because of the theoretical BC's and higher weight, many people assumed the 175 to be a better long-range bullet.

http://www.sierrabullets.com/index.cfm?section=bullets&page=bc&stock_num=2275&bullettype=0

The 155gr Scenar has a G1 of .460, and the 175 SMK is .496 between 1800 and 2800 fps according to Sierra. Most .308's can only run the 175 SMK at around 2600 fps, so the 155gr Scenar at 2800 fps mv beats the 175 SMK for trajectory and flight time out to 1000. Several national & international-level long range shooters settled on the 155 Scen for that reason, before they started shooting .260's and 6.5's of course. Their .308's are now re-barreled in .260 Rem, sold, or are collecting dust.

[RStewart]

Rich:

You need to tell the guys the rest of the story when it comes to competitive shooters selecting a load and bullet.

Would you rather have a bullet of high theoretical BC and holds two minutes at 800 or a load that uses a significantly (.1 or more) lower BC yet holds one minute at 800? For guys who aren't competitive long range shooters, such a decision making scenario is not uncommon.

May pay for the competitive shooters to describe how they decide on a load for their sport.

LR1955

When working up a load, I am more interested in group first and velocity second.

For example, I shoot Mid-Range prone (600 yards) with a Remington .223 with 1:6.5 twist and 30" barrel. It had a Pac Nor barrel and I was single loading Sierra 80 SMK's to a COAL of 2.460" over 24.8 grains of Varget. Accuracy was .5" at 100 with a velocity of 2950 fps. I recently had a Barlein barrel put on it. The throat is shorter, so I now load to 2.410" over 24.4 grains of Varget. The rifle shoots 10 round groups of .214" verified. With this new combo I won my class in a regional in April and have placed in the top 2 in F-TR matches in the last 2 months. I have not chronographed the loads and don't really intend to as it groups really nice at 100 and holds that at 600 yards (with .4 grains less powder it should be a little slower or maybe not because it's more compressed, IDK), but that's good enough for me. Our X-ring at 600 yards is 3" (1/2 moa) and the 10 ring is 6" (1 moa).

I am now going through the same exercise with one of my Grendels (20" Hunter). I have tried BLC-2, Varget, H335, 2520 and 8208 in side by side comparisons with the same bullets. I fired a 5 round group of each and looked at the groupings. The 2520 and 8208 grouped the best with 123 SMK's and 123 AMAX in my 20" rifle. So now, I'm going to load up 22 rounds of each and take it out to 600 yards (22 rounds is a standard match string with 2 sighters and 20 for score). I'll see how they group at that range. Once I go through this exercise, I may chrono the loads, but again, to me it's about accuracy, not speed.

I am by no means an expert on ballastics, bullet coefficients and YMMV, but this is how I do it.

[LRRPF52]

If I was only concerned with the best groups possible out to 600, I would be more concerned with accuracy. Since the wind really makes or brakes you at further distances, especially past 700, I need speed and accuracy, so I watch the nodes carefully in the higher velocities.

+1 for Bartlein's. My .260 Rem has a Bartlein pipe, and it is a shooter, especially with Hodgon's and 139 Scenars (.3-.4" 5-round groups at 100yds). I'm still playing with different bullets and loads for it-just loaded up a bunch of 140 AMAX's and 140 Berger Hunting VLD's. If I can have a good hunting load for it, I'll keep that in my back pocket for any opportunities. I'm trying to get in on a trip with my friends hunting wild boars and deer in the Baltics.

I would like to take the Grendel on that trip as well, and see the comparisons.

[RStewart]

Wind effects on an 80 grain bullet at 600 yards can also be a challenge. Lol!