Powder Load Variation Depending On Shooting Distance

[Shynloco]

I've noted for sometime, that folks write about and post the loads they use for accuracy shooting. They usually provide the caliber, bullet, powder, primer, and casing that gives them their best group size they get out of their rifles. The one variable that often is not listed, is the distance they shoot with that load. For instance, I see some folks shooting a .308 using a Sierra 168 HPBT using 42 grs of Varget, Lapua Brass, CCI BR4 Primer, etc and another shooting 44.5 grs of powder or another fella shooting the same caliber using a 155 gr Lapua Scenar bullet being pushed by 45 gr of Varget using Lapua Brass, CCI BR4 Primer. The first loads I mentioned are being shot at 100 yds and the second is being shot at 1000 yds. Now I know the ladder method is the safest and most reliable way to see what works best in your particular rifle. But I'm curious, how much of a difference in the amount of powder being used, either plus or minus, can be REASONABLY expected if say that same 168 Sierra was now being shot at 1000 yds and that Lapua Scenar was now shot at 100 yds? The reason I ask, is that I shoot and load strictly for accuracy and do it for enjoyment and not competition. But the 100yd range I use is 2.5 miles from my house and I have to drive 75 miles to find a range that allows me to shoot 1000 yds. Any thoughts, suggestions or advice would be greatly appreciated. Thx guys!

 

[spclark]

Sometimes I'll find a load that works great at 1,000 and a reduced load that works well at 600 yards. Advantage here is less powder equals less barrel trauma when mid-range distance is the venue. Ladder testing can help you find accuracy nodes for a particular combo and there's merit to using lower charge weight for short distance.

Much depends on your selected rifle, barrel, chamber profile, and shooting needs. Suggested loads are just that - what works for one shooter might for another using an entirely different combination of hardware, but chances are good that a little 'tuning' (sometimes a LOT :-[ ) is indicated to make a suggested load at the start really perform well in the end.

I do load testing at 100 yards at a range 60 minutes from my back door. The range has a 200-yard capability but it's walk'n'paste for both. I get results at 100 that allow me to pick a load combo for further evaluation when I choose to make the one-way, 2-1/2 hour pilgrimage to the closest 1,000 yard range. Testing at 200 yards doesn't seem to offer much of an improvement in data & I don't have to walk as far

1000 yards presents an entirely different set of conditions compared to 100 yards, everything else being equal. If 90% of your shooting is at short range, work towards loads that work for you at that distance. What works at 100 yards may work fine at 1,000 if you choose bullets that hold their velocity well then load for a velocity that allows them to work at their best.

On using Sierra 168 HPBT's at 1,000 yards? I'm confident some folks might get them to work though most will be disappointed. There are better bullets (a BUNCH!) out there for that distance.

 

[GerryM]

Accuracy is the most important part . A good load is just that a good load. The rifle determines just where it wants to shoot it's best.
A few hundred feet a second won't really help that much if that load isn't accurate.
Usually the heavy bullets are long range but some have used the lighter 155 or 150 match pills out to 1000. The 308 was basicly designed with the 150 or 147 gr bullets for best accuracy. What ever works is the key here. some rifles like hot loads others don't