Most 6.5 Creedmoor shooters prefer heavier bullets. I happen to be one of them. While my favorite bullet for the Creedmoor is the 142 Sierra MatchKing (SMK), it’s slightly lighter, and easier to stabilize little brother, the 140 SMK is also quite popular.
When they stand side by side you’ll notice the 140 SMK (above, left) is also slightly shorter than the 142 SMK (right). This means the 140 will stabilize better in slower twist barrels more than the 142 does; and you’ll see initial factory 6.5 Creedmoor ammunition offerings in the 140 as opposed to the 142 because it can be fired through a larger variety of rifles. In this post I’ll take a look at how the 140 SMK performs in a gas gun with two popular powders, Varget and H4350.
The 6.5 Creedmoor Big Beast features 7075 Aluminum Nib-X coated billet upper and lower receivers, 20″ Match Grade 1/8″ twist button rifled 416 stainless steel barrel, NiB-X coated BCG, Hipertouch 24-E trigger, fixed modular stock with adjustable length of pull and cheekpiece and a low profile M-LOK hand guard (Note this rifle doesn’t have a particularly heavy barrel).
WARNING: The loads shown are for informational purposes only. They are only safe in the rifle shown and may not be safe in yours. Consult appropriate load manuals prior to developing your own handloads. Rifleshooter.com and its authors, do not assume any responsibility, directly or indirectly for the safety of the readers attempting to follow any instructions or perform any of the tasks shown, or the use or misuse of any information contained herein, on this website.
Since this is a gas gun I decided to use new Hornady brass with a CCI #200 primer under Varget powder. All shooting was done prone from a bipod. Velocity information was recorded with a MagnetoSpeed V3 barrel mounted ballistic chronograph.
Group sizes for the 140 SMK with Varget ranged from .777″ (.742) to 1.404″ (1.341 MOA) with an average 5-shot group size of 1.040″ (.993 MOA). Despite the fact that 3 of the 5 loads tested were sub MOA, the Varget loads failed to reliably cycle the rifle. For this reason I would not recommend using Varget with 140 grain class bullets in a semi-automatic 6.5 Creedmoor.
Group sizes for the 140 SMK with H4350 ranged from .651″ (.622 MOA) to 1.394″ (1.331 MOA) with an average 5-shot group size of 1.149″ (1.097 MOA). Only one of the five loads tested with H4350 provided sub MOA results, the 41.1 gr load, and that was quite impressive. All of the H4350 loads cycled the rifle reliably. If I were to select a 140 Grain load for this rifle, it would be that one.
Between the two powders, average group size for the 140 SMK was 1.094″ (1.045 MOA).
NOTE: If you are a regular reader you’ll note that my target looks different. I used to use 1″ orange dots on cardboard targets. They worked in most conditions, however, in heavy rain or extreme cold, the adhesive would fail and they would fall off the target. I developed this target with Rite in the Rain. It is on waterproof stock with true 1.047 MOA green dots. The color provides excellent contrast and you can still see your impacts on the paper. Rite in the Rain sells these targets as well as paper that you can print your own targets on. To learn more about Rite in the Rain and their line of targets, click here.