500-Round Group at 300 Meters — Now That’s a Test!
For load development, some guys shoot 3-shot groups. Other guys shoot 5-shot groups, or even 10-shot strings. But for testing its projectiles, Sierra Bullets takes it to another level entirely. A while back Sierra was testing its .30-Caliber 175gr HPBT MatchKing in the Sierra uynderground tunnel. The results are show above — a FIVE HUNDRED Round group!
The tunnel testers sent five full boxes of bullets down-range. Here are 500 Shots shot in a 300 meter tunnel. The group size is 2.82 inches (that’s edge to edge of the farthest shots, less the bullet diameter). This was a pressure/velocity test for a commercial customer. The Cartridge was .308 Win, loaded at 2.800″.The powder was Reloder 15. A 26″ barrel was shot from a return to battery rest. The gun was cleaned every 125 rounds and two foulers shot.
What do you think — could you beat this group from a bench for 500 rounds?
One Facebook poster joked: “500-round group? Everyone knows anything less than 1000-round groups are a waste of time and statistically irrelevant.”
Sierra’s 300 Meter Testing Tunnel
Ever wonder how (and where) Sierra tests its bullets? The answer is underground, in a 300-meter test tunnel located under Sierra’s factory in Sedalia, Missouri. The photo above shows the construction of the tunnel back in May, 1990. Like most bullet manufacturers, Sierra does live-fire bullet testing of its projectiles. Sierra’s 300-meter test range is the longest, manufacturer-owned underground bullet test facility in the world. Sierra offers free tours of the test tunnel as part of Sierra’s Factory Tour Program.
Similar Posts:
- 500-Shot Group at 300 Meters — Now That’s a Serious Test
- 0.8 MOA for 500 Shots at 300 Meters — Sierra Test Tunnel Result
- Could You Shoot 0.8 MOA at 300m — for FIVE HUNDRED Shots?
- A Look Inside Sierra’s 300m Underground Test Tunnel
- 10 Shots in One Ragged Hole at 200 Yards — Sierra Tunnel Test
Share the post "500-Round Group at 300 Meters — Now That’s a Test!"
Tags: .308 Win, 300 meter, Group, Reloder 15, Sierra Bullets, Sierra Tunnel, Tunnel
If I figured it right that equates to about 3/4 inch at 100yds. is that within Sierra’s standards?
13/16? 8.22 anyone want to check my math?
I wonder what load was used?
Also, it would be instructive the see the growth of the group (running group size average) with every 5th shot. This may give an idea of how valid 5 shot groups are.
Be even more interesting if they had electronic monitoring and could tell how the group size change with time and number of rounds.
300 meters = 328.084 yards
Group of 2.823 divided by 3.28084= .860″ at 100 yards unless using 1 MOA =1.047″
Did Sierra shoot the 500-shot group over an Oehler M43 with acoustic target at 300-m or some similar equipment?
If so, I would love to have the bullet hole coordinate data for each bullet, obtained by an M43 with acoustic target. I would be willing to pay for that information or do some work for the customer who paid for that test.