CZ457 Long Range MTR Muzzle velocity

[RALA]

I have a CZ 457 Varmint. I swapped the 20 in barrel for a 20in Long range MTR fluted threaded barrel. 100 yard groups are better and this barrel likes Federal Match over SK rifle match, both shoot Eley black about the same. what really surprised me is that across the board the MTR barrel is 20-30 FPS faster than the varmint.
All 10 shot averages:

	457 Varmint	457 LR MTR	SD
sk rifle Match	1063	1088	11
Sk-Long Range	1078	1093	3
Federal Match	1089	1115	5
Eley Match (Black box)	1054	1063	7

I'm not complaining. It's a minor tweak in the zero for each brand. Just surprised. Anyone see similar results?

Bob

 

[justin amateur]

Y'er basing y'er analysis on ten shot groups?
Not a sample size I would work with.
50 shots is barely adequate,
100 would be my minimum to provide useful data.
Small sample sizes can lead to incorrect conclusions.
Rimfire is not a cartridge type known for producing consistent velocities.

Testing was done same day? Same conditions?
No temperature variations? Same lot numbers?

No two barrels are identical.
Chamber dimensions will affect brass expansion volume and change pressure peak.
Bore finish and dimensions will differ and affect how the bullet accelerates through the barrel.